BASICS OF THE BASIN NINTH BIENNIAL RESEARCH SYMPOSIUM · 2020. 6. 23. · Mark Schexnayder LSU...

BASICS OF THE BASIN NINTH BIENNIAL

RESEARCH SYMPOSIUM ADDRESSING THE CONDITION OF THE LAKE PONTCHARTRAIN BASIN

A research forum organized by The Pontchartrain Research Committee & The Gulf Estuarine Society

November 5, 6 and 7, 2008 UNIVERSITY OF NEW ORLEANS

FUNDING PROVIDED BY:

U. S. GEOLOGICAL SURVEY - CENTER FOR COASTAL AND WATERSHED STUDIES U.S. ARMY CORPS OF ENGINEERS

LOUISIANA DEPARTMERNT OF NATURAL RESOURCES U. S. GEOLOGICAL SURVEY – NATIONAL WETLANDS RESEARCH CENTER

PONTCHARTRAIN INSTITUTE FOR ENVIRONMENTAL SCIENCES - UNO COALITION TO RESTORE COASTAL LOUISIANA

LSU AGCENTER MOFFATT & NICHOL

SOUTHEASTERN LOUISIANA UNIVERSITY LAKE PONTCHARTRAIN BASIN FOUNDATION

HDR

Basics of the Basin 2008

CONTENTS FUNDING AND SUPPORT .................................................................................3 PONTCHARTRAIN RESEARCH COMMITTEE................................................4 DR. SHEA PENLAND…………………………………………….. …….………6 GULF ESTUARINE RESEARCH SOCETY…………….……… ………………7 LUNCHEON SPEAKERS………………………………………….. ..……….….8 PIROGUE AWARDS…..........................................................................................9 PROGRAM.................….......................................................................................10 RESEARCH SUMMARIES ………………………………….…………….........16

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FUNDING AND SUPPORT

Financial support was received by the following organizations:

U. S. GEOLOGICAL SURVEY - CENTER FOR COASTAL AND WATERSHED STUDIES

U.S. ARMY CORPS OF ENGINEERS

LOUISIANA DEPARTMERNT OF NATURAL RESOURCES

U. S. GEOLOGICAL SURVEY – NATIONAL WETLANDS RESEARCH CENTER

PONTCHARTRAIN INSTITUTE FOR ENVIRONMENTAL SCIENCES – UNO

COALITION TO RESTORE COASTAL LOUISIANA

LSU AGCENTER

MOFFATT & NICHOL

SOUTHEASTERN LOUISIANA UNIVERSITY

LAKE PONTCHARTRAIN BASIN FOUNDATION

HDR

Thanks to Dr. Mike Poirrier, President of GERS, for his collaboration. Administrative support was provided by the UNO Conference Services. In particular, thanks to Patti Wolf. The Pontchartrain Research committee thanks these organizations and their representatives for their continuing support.

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PONTCHARTRAIN RESEARCH COMMITTEE The Pontchartrain Research Committee (PRC) was formed in 1992 shortly after the first "Basics of the Basin" research Symposium was held. The mission of this committee is to promote good science for the Pontchartrain Basin. Committee members also have been called upon in an advisory capacity to various governmental and environmental groups. The PRC welcomes these opportunities such as this to share ideas and resources. This committee plans to continue to be active and is willing to consider project proposals related to the basin. We intend to continue to work closely with the scientific community, and with environmental groups whose primary concern is the Pontchartrain Basin. We also intend to continue to hold this symposium biennially. 2008 PRC MEMBERS Dr. John A. Lopez--Committee Chairman Lake Pontchartrain Basin Foundation 31378 River Pines Dr. Springfield, La. 70462 H (225) 294-4998 504 421-7348 Cell [email protected] Dr. Chris Brantley U.S. Army Corps of Engineers Project Manager – Bonnet Carré Spillway New Orleans District

[email protected] (985) 764-0126 #6 Mark Davis

Director - Tulane Institute on Water Resources Law and Policy 6329 Freret St. Suite 359C New Orleans, LA 70118 504-865-5982 504-862-8844 fax [email protected] www.law.tulane.edu/enlaw

Dr. Robert W. Hastings 141 N. Northington Street Prattville, AL 36067 334-491-0780 334-324-1071 (cell) [email protected]

Carol Franze Associate Area Agent St. Tammany/Tangipahoa LA Sea Grant Marine Extension/ LSU Ag Center Research & Extension 21549 Old Covington Hwy. Hammond, Louisiana 70403 Office: (985) 543-4129 Mobile: (985) 222-4962 [email protected]

Dr. Mark Kulp University of New Orleans - Lakefront Campus Department of Earth and Environmental Science New Orleans La W (504) 280-1170 [email protected] Dr. Alex McCorquodale University of New Orleans Dept of Civil Engineering W (504) 280-6074 [email protected] Greg Miller U.S. Army Corps of Engineers New Orleans District (504) 862-2310 [email protected] Dr. Michael Poirrier University of New Orleans Dept. of Biological Sciences - Emeritus W 280-7041 [email protected]

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Dr. Andrea Calvin Lake Pontchartrain Basin Foundation PO BOX 6965, Metairie, La. 70009 W (504) 836-2215 [email protected] Mark Schexnayder

LSU AgCenter/Louisiana Sea Grant 6640 Riverside Drive, Suite 200 Metairie, LA 70003 504/838-1170 504 908- 9718 cell [email protected]

John Troutman (CPRA) La. Dept. of Natural Resources - Coastal Restoration Division New Orleans Field Office (UNO Campus) W (504) 288-5330 [email protected]

Dawn Lavoie, Ph.D. USGS - Science Coordinator, Gulf Coast and LMV UNO, 2000 Lakeshore Drive New Orleans, LA 70148 504 280-4054 [email protected] Mr. Randolph Joseph

Area Conservationist NRCS – Lafayette, LA 337- 291-3050 [email protected]

Robert Dubois U.S. Fish and Wildlife Service 646 Cajundome Blvd. Suite 400 Lafayette, La. 70506 [email protected] (337) 291-3127

Dr. Jimmy Johnston HDR Suite 1216 One Galleria Metairie, La. 504 837-6681 C 504 906-5100 [email protected]

Bren Haase La Department of Natural Resources (CPRA) 617 North 3rd St. Baton Rouge, LA 225 342-1475 [email protected]

Dr. Robert Moreau Turtle Cove Environmental Research Station Southeastern Louisiana University Box 10585 (Physical Address: 1101 N. Oak St.) Hammond, Louisiana 70402 Office Phone: (985)549-5008 Office Fax: (985)549-5068 [email protected]

Dr. Jim Flocks USGS - CENTER FOR COASTAL AND WATERSHED STUDIES St. Petersburg, Florida 727 803-8747 X3012 [email protected]

Dr. Mark Hester University of Louisiana - Lafayette Lafayette, LA 337 482-1492 C 504 237-1151 [email protected]

Natalie Snider Coalition to Restore Coastal Louisiana 6160 Perkins Road Baton Rouge, LA 70808 225 767-4181 C 225 303-3567 [email protected]

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Shea was a founding member of the Pontchartrain Research Committee who had an untimely death earlier this year.

Tribute from the Ponthchartrain Institute for Environmental Sciences Website:

Coastal Researcher, PIES Director Shea Penland Dead at Age 54

Dr. Patrick S. "Shea" Penland, one of Louisiana's leading coastal scientists and director of The University of New Orleans Pontchartrain Institute for Environmental Sciences, was found dead on Tuesday, March 25. He was 54.

Dr. Penland, a coastal geomorphologist who held the Jules and Olga Braunstein Professorship in Petroleum Geology, spent more than two decades investigating the geology, geomorphology and shoreline processes of the Gulf of Mexico, Alaska, U.S. Pacific and Atlantic coasts, the Great Lakes, Canada and the North Sea. The goal of his research was to explain the geological evolution of coastal regions and man's role in modifying these landforms.

"Shea Penland devoted his life and distinguished career to understanding the complex dynamics of America's vast labyrinth of fragile coastlines," said John Lombardi, president of the Louisiana State University System. "He was among the first researchers to sound the alarm about impending disaster from the continued loss of marshlands in Louisiana through his numerous scientific studies, which helped us better understand the devastating impact of man on these vital yet precarious barriers. On behalf of the entire Louisiana State University system, I extend my condolences to his family and his colleagues at The University of New Orleans."

At the time of his death, Dr. Penland was completing a study titled "Natural and Human Causes of Coastal Land Loss in Louisiana: The Mississippi River Delta Plain." Since 1979, he published more than 100 scientific papers, received several science awards, conducted more than 30 field trips and chaired more than 30 scientific meeting sessions on coastal geomorphology and processes. In 1995, Dr. Penland delivered the keynote symposium lecture for the annual meeting of the Geological Society of America in New Orleans titled "The Mississippi River - Control and Consequences."

"Through Dr. Penland's efforts as Director of the Pontchartrain Institute for Environmental Sciences (PIES), and through his ongoing research, he became a nationally recognized leader in the field of coastal studies and coastal restoration," said Chancellor Timothy P. Ryan. "At UNO, we were privileged to have claimed Shea as one of our own. We have lost an esteemed teacher, a colleague and a friend."

Dr. Penland joined UNO in 1997. From 1992 to 1997, he was associate professor at the Coastal Studies Institute and directed the Oil Spill Contingency Planning Program, both for the Center for Coastal, Energy and Environmental Resources at Louisiana State University. He had previously served as acting associate director of the Louisiana Geological Survey at LSU, and as a coastal geology section chief for the Louisiana Geological Survey-Coastal Geology Section for the Louisiana Department of Natural Resources.

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Our Mission The Gulf Estuarine Research Society is a not for profit educational organization for people interested in estuarine and coastal issues centering on the Gulf of Mexico.

Promoting Research in the Gulf of Mexico GERS is a very active research society with a membership of scientists, researchers, and students from universitites, agencies and research labs along the Gulf Coast.

President Mike Poirrier

Treasurer Suraida Nanez-James Thanks to Mike Poirrier and Carol Franze of the University of New Orleans for volunteering to act as hosts for the New Orleans Meeting.

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Wednesday Lunch Speaker

Dr. John Lopez

A new generation of river diversion designs considering legacy structures, delta hydrology, and the urgency of

the coastal land loss crisis

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Thursday Lunch Speaker

Dr. Worth D. Nowlin Jr.

The Gulf of Mexico Coastal Ocean Observing System

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Pirogue Award The Pirogue awards began in 1994 and are awarded to those individuals who have made outstanding contributions to BASICS OF THE BASIN SYMPOSIUM. These are “Chairman Awards” selected by the Pontchartrain Research Committee Chairman.

2008 Recipients Senator Mary Landrieu

Dr. Worth D. Nowlin Jr.

Past Recipients

1994 Dr. Michael Poirrier Dr. George Flowers Dr. Robert Hastings

Dr. Shea Penland Dr. Jeff Williams

Dr. Richard Miller Dr. Michael Hirshfield

Mark Davis

1996 Julia Sims

Cliff Kenwood Neil Armingeon

Ann Jakob

1998 Dr. Don Barbe’ Dr. Don Davis

Carlton Dufrechou Dr. Jack Kindinger Dr. Frank Manheim

Dr. Alex McCorquodale Ben Taylor

Dr. Jeff Waters

2000 Chris Brantley

Dr. Quay Dortch Claudia Fowler Carol Franze

Dr. Matt Gould Greg Miller

Anne Rheams

Dr. Gene Turner David Vigh

2002

Mark Schexnayder Dr. Mark S. Peterson Dr. Jimmy Johnston

John Troutman Dr. A.J. Englande

2004

Patricia Arteaga Andrea Calvin

Dr. Mark Hester Dr. Mark Kulp Dr. John Lopez

MOTIVA Kerry St. Pe’

Congressman David Vitter

2006 Dr. Dawn Lavoie

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Basics of the Basin Ninth Biennial Research Symposium Pontchartrain Research Committee & the Gulf Estuarine Research Society

Location: Lindy Boggs International Conference Center - UNO Program

Wednesday, November 5, 2008 8:00-9:00 On-site (Late) Registration

9:00-9:10 Welcome and Announcements

Environmental Education 9:10 Maygarden, D.F., and H. L. Egger. Development of coastal wetlands education in the Lake Pontchartrain

Basin: A ten-year retrospective

9:30-10:30 Hurricanes and Other Disturbances Session Chair: Dr. Mark Kulp

9:30 Miner, M.D., M.A. Kulp, I. Georgiou, D. FitzGerald, J. Flocks, D. Twitchell, and A. Sallenger. The Role of Hurricanes in the Long-Term Evolution of the Chandeleur Islands: Implications for Barrier Management

9:50 Rogers, B. and M. Kulp. Transgressive Evolution of the St. Bernard Shoals

10:10 Ellinwood, M.C., M.T. O’Connell, and C.S. Schieble. Response of barrier island fish assemblages to impacts from multiple hurricanes: assessing resilience of Chandeleur Island fish assemblages to Hurricanes Ivan (2004) and Katrina (2005)

10:30–10:50 Morning Break

10:50-12:10 Hurricanes and Other Disturbances, Continued 10:50 Whitbeck, J.L. Comparative influence of chronic sea level rise vs. acute hurricane disturbance on coastal

bottomland hardwood forest productivity

11:10 Ford, M.A. Disturbed: A 15 Year Profile of Hurricanes, Drought, Flood, and Fire in the Resilient Pearl River, Louisiana Ecosystem

11:30 Kennedy, T.B. The Pearl River Basin: assessing current river condition from bank to bottom, and bottom to top

11:50 Alleman, L.K. and M.W. Hester Trade-offs Between Growth and Reproduction Following Disturbance in a Southern Louisiana Black Mangrove Population

12:10-1:30 Lunch with Invited Speaker:

Introduced By: Dr. Mark Kulp Lopez, J.A. A new generation of river diversion designs considering legacy structures, delta hydrology, and the urgency of the coastal land loss crisis

1:30-2:30 Wetland Plant Restoration Ecology Session Chair: Dr. Julie Whitbeck

1:30 Farve, M., T. Forman and J.L. Whitbeck Roles of seed source, site salinity and nursery practices on cypress sapling performance in restoration plantings in the LaBranche Wetlands bordering Lake Pontchartrain, Louisiana

1:50 Hester, M.W. and J.M. Willis. Status and Trends of the Bucktown Created Marsh: A Southshore Success Story?

2:10 Pickens, C.N. and M.W. Hester. Impact of Cold Temperatures on Early Life History Stages of Black Mangrove (Avicennia germinans (L.) L.): Implications for Restoration

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Wednesday, November 5, 2008 Program, Continued

2:30-2:50 Afternoon Break

2:50–3:30 Blue Crabs and Benthic Invertebrates Session Chair: Carol Franze

2:50 Lyncker, L.A. Blue Crab Migratory Routes into Lake Pontchartrain

3:10 Ray, G.L., E. Behrens. Characterization of Benthic Invertebrate Communities of the Southern Lake Pontchartrain Shoreline, Summer 2007

3:30-4:30 Submersed Aquatic Vegetation (SAV) and Seagrasses Session Chair: Carol Franze

3:30 Nica, C. and H.J. Cho. Report on Seagrass Beds of Ruppia maritima and Halodule wrightii at Grand Bay National Estuarine Research Reserve, Mississippi

3:50 Jones, J., and H.J. Cho. A Study on Organic Dormancy and Germination of Estuarine Ruppia maritima seeds for Laboratory Propagation and Habitat Restoration

4:10 Kirui, P. and H.J. Cho. Hyperspectral Analysis for Improved Image Classification of Shallow Estuarine Submerged Aquatic Vegetation

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Thursday, November 6, 2008 Program

8:00-9:00 Fish and Turtle Biology Session Chair: Dr. Marty O’Connell

8:00 Haskett, K., and G. Guillen. Population Status And Demographics Of The Diamondback Terrapin In West Bay (Galveston Bay, Texas)

8:20 Ramirez, D., and G. Guillen. The Relationship Between Environmental Characteristics And Invasive Fish Species In Oligohaline Coastal Tributaries Of Galveston Bay During Summer Months

8:40 Tyler, A.J., and R. Lehnert. Age and growth of the littlehead porgy, Calamus proridens, from the central west coast of Florida

9:00–10:00 Hypoxia and Water Quality Session Chair: Dr. Mike Poirrier

9:00 Hodges, B.R. The physics of episodic hypoxia in Corpus Christi Bay

9:20 Froeschke, J. and G.W. Stunz. The effect of hypoxia on habitat selection of juvenile estuarine fishes

9:40 Ryckman, L.Y.C., E.J. Buskey, and P.A. Montagna. Effects of seasonal hypoxia on harpacticoid copepod community structure in the northern Gulf of Mexico

10:00-10:20 Morning Break

10:20–11:40 Hypoxia and Water Quality, continued 10:20 Mooney, R. and J.W. McClelland. Nitrogen dynamics during and after storm events in the Mission-

Aransas National Estuarine Research Reserve

10:40 Arismendez, S.S., H. Kim, and J. Brenner. Anthropogenic effects on nutrient loadings and ecosystem responses in the Guadalupe Estuary, Texas, USA: a modeling study

11:00 Guillen, G., J. Wrast, and D. Ramirez. Factors affecting water quality in Lake Madeline (Galveston, Texas): implications for design of waterfront communities

11:20 Bourgeois-Calvin, A. Wastewater Source Detection and Correction in Tangipahoa Parish

11:40-1:00 Lunch with Invited Speaker

Introduced By: Dr. Tom Soniat Nowlin, W.D., Jr., and A.E. Jochens. The Gulf of Mexico Coastal Ocean Observing System

1:00-2:00 Toxic Algal Blooms and Sentinels of Estuarine Health Session Chair: Dr. Tom Soniat

1:00 Smith, A., and J. Mott. Investigation of Sources of E. coli Isolated from Potentia l Oyster Harvesting Waters, Cedar Lakes, Texas

1:20 Swanson, K.M., and T.A. Villareal. The 2008 Dinophysis bloom along the Texas coast: distribution and toxicity

1:40 Soniat, T.M., S.M. Ray, L. Robinson, P. Banks, J. Supan, B. Randall, S. Powers, M. Berrigan,and A. Volety. Oyster Sentinel: monitoring oyster disease and the health of Gulf of Mexico estuaries

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Thursday, November 6, 2008 Program, continued

2:00-2:20 Afternoon Break

2:20-4:40 Bonnet Carré Spillway Opening of 2008 Session Chair: Dr. Chris Brantley

2:20 Killgore, K.J., J.J. Hoover, R.T. Ruth, R.E. Boe, and C.G. Brantley. Rescue of the Federally Endangered Pallid Sturgeon Entrained During Operation of the Bonnet Carré Spillway

2:40 O’Connell, M.T., A.M.U. O’Connell, B. Lezina, C.S. Schieble, and J.M. Van Vrancken. Lake Pontchartrain fishery-independent data and the 2008 Bonnet Carré Spillway opening: a comparison of historic and post-opening surveys

3:00 Roblin, R., A. McCorquodale, and I. Georgiou. Water Quality Modeling of 2008 Bonnet Carré Diversion into Lake Pontchartrain

3:20 Li, C. Y., J.R. White S. Bargu, N. Walker, W. Fulweiler, and R.R. Twilley, Characteristics of the 2008 Bonnet Carré Spillway Plume in Lake Pontchartrain: Measures of water quality, total suspended solids and plankton communities

3:40 Burris, R., M. Brainard, M. Buchanan, M. Hill, and D. Diaz. Monitoring and Assessment of the 2008 Bonnet Carre´ Spillway Opening in Mississippi Sound, MS

4:00 Chou, J., T. Tian, G. Clement, T. Ilgen, A. Dantin Bin Huang, and Robert Gambrell. Effect of the Opening of Bonnet Carré Spillway on Distribution of Heavy Metals in Lake Pontchartrain

4:20 Risley, R.R.; Voegel, P.D.; and J. D. Stricks, Changes in Nutrient, Conductivity and Chlorophyll a following the Opening of the Bonnet Carre Spillway

4:40-5:10 GERS Business Meeting

4:50-6:30 Reception and Poster Session

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Thursday

4:50-6:30 Reception and Poster Session

Posters and Video Bethel, M. and L. Martinez. Assessment of Seagrass Critical Habitat in Response to Dramatic Shoreline Change Resulting from the 2005 Hurricane Season for the Chandeleur Islands

Egger H. L. and D.F. Maygarden. The Development of a Coastal Education Program at the Coastal Education and Research Facility at Chef Pass

Fischer, M.R., and W.C. Padgett. Pontchartrain Basin Coastal Land and Marsh Vegetative Type Trends

Howard, A.C., E.A. Spalding, A.E. Walker, and M.A. Poirrier. The interaction of salinity, low dissolved oxygen and blue crab predation on Rangia clam survival

Keddy, P., J.A. Nyman, and J. Siegrist. The Prospect for Biological Control of Nutria by Alligators

Martinez, L.A., S. Penland, S. O’Brien, M. Bethel, F. Cretini, P. Guarisco, I. Lacour , and D. Lee. Historical Shoreline Changes and Barrier Island Land Loss along Louisiana's Gulf Shoreline: 1800's–2005

McInnis, N.C., and B. Rogers. Priority Conservation Areas in the Lake Pontchartrain Estuary Zone

Mishra, S., and D.R. Mishra. Effect of Bonnet-Carrie Spillway opening on spatio-temporal variability of water quality parameters in the Lake Pontchartrain

Padgett, C. Summary of Louisiana Coastal Protection and Restoration (LACPR) Planning Unit 1 (Pontchartrain

Basin) Alternatives

Ross, A., A. Wallace, B. Tansy, D. Tillman, A. Leaf, A. Perzdock, D. Cornelius, H. Yoshida, and M. Scott. Community-led Urban Wetland Restoration in New Orleans’ Lower 9th Ward: The University of Wisconsin’s Biological and Social Science Characterization

Reed, D., A. Commagere, and M. Hester. The implications of Hurricane Katrina and altered nutrient regimes on long-term trends in marsh elevation at Big Branch National Wildlife Refuge, Louisiana

Whitbeck, J.L., J.C. Roberts, and T. Forman. Cypress saplings survive four weeks of complete submergence

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Friday, November 7, 2008 Program

8:00-10:00 Coastal and Wetland Restoration Session Chair: Dr. Alex McCorquodale

8:00 Lopez, J.A., N. Snider, P. Kemp, and C. Dufrechou. Application of the Multiple Lines of Defense Strategy to Planning Units 1 and 2 in southeast Louisiana

8:20 Snider, N. The Future of Louisiana: not a model FROM the Netherlands but a model FOR the Netherlands

8:40 Georgiou, I.Y., J.A. McCorquodale, A.G. Retana, J. Schindler, D.M. FitzGerald, and Z. Hughes, Hydrodynamic and Salinity Modeling of Mississippi River Diversion Flows: Violet, Louisiana

9:00 Wilkinson, L.L., A. S. Grzegorzewski, and L. Walker. Environmental Impacts of the MRGO Closures at Bayou la Loutre and Bayou Bienvenue

9:20 Lopez, J., P. McCartney, M. Kulp and P. Kemp. The Bohemia Spillway in southeast Louisiana: what little we know and what we should know

9:40-10:00 Morning Break

10:00-12:30 Discussion Panel:

Vegetative and Soil Responses to Marsh in Vicinity to Freshwater Diversions

Co-Facilitators:

Jenneke Visser

John Lopez

Panelists:

Greg Snedden

Robert Twilley

John Barras

Mark Kulp

Chuck Villarubia

Chris Swarzenski

Gary Shaffer

Gene Turner

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Research Summaries (in alphabetical order of the presenter - underlined)

Trade-offs Between Growth and Reproduction Following Disturbance in a Southern Louisiana Black Mangrove Population Alleman, L.K. and M.W. Hester¹. University of Louisiana, Lafayette. Department of Biology. PO Box 42451. Lafayette, LA 70504.

Effectiveness of salt marsh restoration, especially in high-energy environments, is enhanced by the rapid establishment of vegetation to stabilize substrates. Native woody species are especially desirable for restoration because they add significant structure and habitat complexity to these coastal marshes. A sound ecological understanding of the life histories of the salt marsh plant communities is crucial to managing and improving the resilience of the coastal marshes and barrier islands in Louisiana. Black mangroves (Avicennia germinans) are a native woody species found on Louisiana barrier islands and coastal marshes and occur as a dwarf-type that do not grow to the same height as in the tropics due to temperature constraints. There are established populations of black mangrove in southern Louisiana that integrade into areas dominated by the herbaceous salt marsh species Spartina alterniflora, such as at the back barrier marshes of the Caminada-Moreau Headland near Port Fourchon, where this study was conducted. Louisiana black mangroves produce mature propagules in mid October. Propagules can be distinguished from seeds by the stages of development they undergo following fertilization; propagules do not pass through a dormant period prior to germination, hence mangroves are known as a viviparous species. For this study, the height, diameter, and propagule production of the same 50 trees were measured in mid-October of 2005, 2006, and 2007. The sampling began in 2005, following Hurricane Katrina. Since the same trees are measured annually, both individual and population-level growth and propagule production rates can be estimated. Reproductive potential can vary depending on the relative allocation of the plant’s energy resources to growth, sexual reproduction, or maintenance. Therefore, the number of propagules produced per area or volume of mangrove canopy may be a useful metric of population reproductive output that can be exploited by managers in the context of utilizing propagules, rather than nursery-grown seedlings, as the dispersal agent for restoration. It is also of interest in the study of the autecology of the species in this region, since Louisiana is the northernmost latitudinal extent of black mangrove in North America. Results to date indicate that at the population level, average height, canopy volume, and propagule production were all lowest in the October 2005 census, which was in the aftermath of Hurricane Katrina (Aug 29, 2005 landfall), relative to the subsequent years. In 2006 the average propagule production more than doubled, but in 2007 propagule production did not increase significantly. In contrast, height and volume increased more in 2007 than in 2006. At the level of the individual, reproductive potential varied dynamically. Interestingly, inverse trends were noted for propagule production by year, with a trend towards increased propagule production in 2006 relative to 2005, followed by decreased production in 2007 relative to 2006. In some cases, the difference in magnitude of increase in propagule production from 2005-2006 was nearly equal to the magnitude of decrease in propagule production from 2006-2007. This pattern was most evident in the larger, older cohort of trees as compared to the smaller, younger individuals. Propagule production per volume of mangrove was greatest in 2006. Due to energetics, the total allocation of resources by plants among growth, reproduction, and maintenance is limited, resulting in the occurrence of trade-offs. If a plant invests most of its resources into growth, it logically follows that fewer resources will be available for reproduction. Following Hurricane Katrina, trees appeared to allocate resources to repair and maintenance at the cost of reproductive output. By 2006, the recovering trees increased their propagule production by allocating resources to reproduction at the expense of growth. However, in 2007, tree size (height, area, and volume) increased significantly and propagule production was very similar to that in 2006. Continued annual sampling of these trees will elucidate whether these patterns are a cyclic phenomenon driven primarily by the energy allocation to sexual reproduction in the previous year, or are a response to environmental factors..

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Anthropogenic effects on nutrient loadings and ecosystem responses in the Guadalupe Estuary, Texas, USA: A modeling study Arismendez, S.S., H. Kim, and J. Brenner. Harte Research Institute for Gulf of Mexico Studies, Texas A&M University-Corpus Christi, Corpus Christi, Texas.

Estimates place between 53 to 60 percent of the U.S. population living within 60 kilometers of the coast with hot spots of population growth identified along the Texas Gulf Coast (Crossett 2004, Culliton 1998). Increases in human population results in increased development and concomitant environmental pressures such as nutrient loadings. Nutrient enrichment from nonpoint or diffuse sources of pollution now represent the largest pollution problem facing coastal waters in the United States with more than 60 percent of coastal U.S. waters being moderately to severely degraded by nutrient pollution (Howarth et al. 2000). Of those 60 percent, degradation is particularly severe in coastal waters of both the mid Atlantic states and the Gulf of Mexico. The goal of the present study, therefore, is to identify differences between the Guadalupe and San Antonio River Basins, determine how these differences affect nutrient loadings, and to determine how the estuarine ecosystem responds.

The Guadalupe Estuary is one of seven major estuarine systems centrally located along the Texas Gulf coast and is among the top three Texas estuaries with the most productive resource base for commercial bay fisheries (TDWR 1980). Two major river basins drain to the Guadalupe Estuary, the Guadalupe and San Antonio River Basins, both of which differ in size, population, urban land use, precipitation and permitted discharges.

To investigate anthropogenic effects of nutrient loadings on estuarine responses, an ecosystem model coupled with 3-compartments was developed. The model domain includes two segments neighbored by two watersheds and one segment at the seaward boundary (Gulf Inlet). We analyzed historical data from the Lower San Antonio and Guadalupe River Watersheds and found mean concentration of dissolved inorganic nitrogen for the period of record was an order of magnitude higher in the Lower San Antonio River Watershed than in the Lower Guadalupe River Watershed. The model also revealed different ecosystem responses to different nutrient loading scenarios.

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Assessment of Seagrass Critical Habitat in Response to Dramatic Shoreline Change Resulting from the 2005 Hurricane Season for the Chandeleur Islands Bethel, Matthew and Luis Martinez. Pontchartrain Institute for Environmental Sciences, University of New Orleans, 2045 Lakeshore Drive, New Orleans, LA 70148,

Figure 1. Map showing Seagrass Change Analysis from January 2005 to October 2005.

UNO-PIES mapped seagrasses at the North Chandeleur Islands using remotely sensed imagery acquired in January 2005 (pre-storm events) and October 2005 (post-storm events). Our goal was to estimate total seagrass cover just prior to and following the 2005 hurricane season and then assess any change over that time. The results of the change analysis show that there were 524 acres of seagrass bed loss in the study area over this period of time (Figure 1). This change represents a 20% decrease in the total seagrass acreage existing in the study area. The North Chandeleur Islands experienced a 70% loss of land during the 2005 hurricane season. Given that this area bore the brunt of Hurricane Katrina's destructive forces, the seagrass beds here proved remarkably resilient. The results indicate seagrass bed loss occurred primarily where no protective barrier island was left in October 2005, though proved sustainable where only minimal emergent land existed following the 2005 storms.

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Rescue of the Federally Endangered Pallid Sturgeon Entrained During Operation of the Bonnet Carré Spillway Killgore, K.J.1, J.J. Hoover1, R.T. Ruth2, R.E. Boe3, and C.G. Brantley3. 1Engineer Research and Development Center, Environmental Laboratory, 2Louisiana Department of Wildlife and Fisheries, Baton Rouge, LA, 3U.S. Army Corps of Engineers, New Orleans District, New Orleans, LA. The Bonnet Carré spillway was constructed in response to the 1927 flood to protect New Orleans. The spillway diverts water from the Mississippi River into a floodway that empties into Lake Pontchartrain to reduce flood stages downstream; design capacity flow is 250,000 cfs. The Corps opened the spillway for the first time in 11 years on April 11, 2008. Within nine days, a total of 160 bays were open diverting a maximum flow of 160,000 cfs from the Mississippi River. The structure was completely closed May 8, 2008, and was therefore operational for almost one month.

Shortly after the Bonnet Carré spillway was open, the federally-endangered pallid sturgeon (Scaphiryhnchus albus) was captured in the Mississippi River near the structure, suggesting that this species could be entrained through the spillway into Lake Pontchartrain. The pallid sturgeon was listed as an endangered species in 1990 (Federal Register 1990). It ranges throughout the Mississippi and Missouri River basins, although no individuals have been captured below New Orleans (Carlson et al. 1985; Killgore et al. 2007).

The pallid sturgeon is a freshwater, riverine species and it was assumed that any individual entrained into Lake Pontchartrain would not survive in this brackish, laucustrine environment. Once the structure was closed, the Corps and Louisiana Department of Wildlife and Fisheries (LDWF) began sampling the floodway for sturgeon to evaluate entrainment. We surmised that the most likely location where sturgeon would be concentrated was in the upper end (closest to the structure) of Barbar canal, the primary distributary in the floodway (Figure 1). Water leaked through the structure maintaining flow in Barbar canal after closure. Within one hour of setting a gill net, the first pallid sturgeon was caught.

Multiple gears were used over a five-week period in an attempt to capture pallid sturgeon, including electroshocking, gill nets, hoop nets, trotlines, trawling, and seining. With one exception, pallid sturgeon were only collected by electroshocking (effort=15 hours) and with gill nets (effort=20 net-sets of 1 day each). One pallid sturgeon was collected at the base of the structure by seining with a gill net. A total of 14 pallid sturgeon were collected below the structure in Barbar canal over a 3-week period. Other locations were sampled in the floodway, including its confluence with Lake Pontchartrain, but no sturgeon were captured except at the upper end of Barbar canal. We assume that because pallid sturgeon are strongly rheotactic (Adams et al., 1999), individuals displaced downstream, oriented into the direction of the flow, and moved towards the base of the structure, against the current, until they reached an impassable road crossing where they were susceptible to capture.

Sampling continued for two more weeks, but no additional pallid sturgeon were collected (Figure 2). In addition, 41 shovelnose sturgeon (S. platorynchus), a non-federally endangered, sympatric species were captured below the structure. All sturgeon were measured, tagged, and released back into the Mississippi River. Five weeks after closure, Barbar canal became dewatered and the sampling was discontinued. Overall, fifty-two species of fish, including sturgeon, were documented in the floodway of the Bonnet Carré spillway over a five-week period after the structure was closed.

Under Section 9 of the Endangered Species Act, it’s unlawful to “harass, harm, wound, or kill” an endangered species. Therefore, the presence of pallid sturgeon below Bonnet Carré Spillway, assuming all were entrained from the Mississippi River, constitutes a “take” under the Act. Pursuant to Section 7 of the Act, an incidental take of an endangered species requires consultation with the U. S. Fish and Wildlife Service. The purpose of consultation is to determine specific actions that will reduce or eliminate incidental take during future operations of the spillway. This process is ongoing and will result in formal recommendations. However, the capture of sturgeon below the structure and relocation back to the Mississippi River demonstrates that a “rescue” effort can successfully minimize “take” of this federally endangered species entrained during operation of the Bonnet Carré Spillway.

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References Cited Adams, S.R., J.J. Hoover, and K.J. Killgore. 1999. Swimming endurance of juvenile pallid sturgeon, Scaphirhynchus albus. Copeia 1999: 807-807. Carlson, D. M.; Pflieger, W. L.; Trial, L.; Haverland, P. S., 1985: Distribution, biology, and hybridization of Scaphirhynchus albus and S. platorynchus in the Missouri and Mississippi rivers. Env. Biol. Fish. 14, 51-59. Federal Register, 1990: Determination of endangered status for the pallid sturgeon; final rule. Sept. 6, 1990. 55(173), 36641-36647. Killgore, K. J., J. J. Hoover, S. G. George, Br. R. Lewis, C. E. Murphy, and W. E. Lancaster. 2007. Distribution, Relative Abundance, and Movements of Pallid Sturgeon in the Free-Flowing Mississippi River. J. Applied Ichthyology 23, 476-483.

Figure 1.The upper end of Barbar canal immediately below the Bonnet Carré Spillway where all pallid sturgeon were collected. Note the water leaking from the bays after the structure was closed, providing adequate flows to maintain sturgeon in the canal. This picture was taken approximately one week after the structure was closed, and within five weeks after closure, Barbar’s was completely dewatered.

Figure 2. Numbers of shovelnose and pallid sturgeon collected in Barbar canal below the Bonnet Carré Spillway 1 to 5 weeks after the structure was closed. Sampling ceased after the canal became dewatered at the end of week 5.

0

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Table 1. Fish species collected below Bonnet Carré spillway during May and early June 2008.

Scientific name Common name Number Collected

Family Acipenseridae Scaphirhynchus albus Pallid sturgeon 14 Scaphirhynchus platorynchus Shovelnose sturgeon 41 Family Polyodontidae

Polydon spathula Paddlefish 7 Family Lepisosteidae Atractosteus spatula Alligator gar 5 Lepisosteus oculatus Spotted gar 16 L. osseus Longnose gar 6 Family Amiidae Amia calva Bowfin 1 Family Anguillidae

Anguilla rostrata Freshwater eel 64 Family Engraulidae Anchoa mitchilli Bay anchovy 1 Family Clupeidae Alosa chrysochloris Skipjack herring 232 Brevoortia patronus Gulf menhaden 11 Dorosoma cepedianum Gizzard shad 122

D. petenense Threadfin shad 65 Family Cyprinidae Cyprinus carpio Common carp 10 Hypophthalmichthys molitris Silver carp 3 Hypophthalmichthys nobilis Bighead carp 1

Macrhybopsis aestivalis Speckled chub 2 Macrhybopsis storeriana Silver chub 2

Notropis atherinoides Emerald shiner 2 Notropis shumardi Silverband shiner 1 Notropis wickliffi Channel shiner 5 Notropis spp. Minnow/shiner juvenile 2 Family Catostomidae Carpiodes spp. Carpsucker juvenile 1 Carpiodes carpio River carpsucker 3 Ictiobus bubalus Smallmouth buffalo 15 I. cyprinellus Bigmouth buffalo 1

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I. niger Black buffalo

1

Table 1. Fish species collected below Bonnet Carré spillway during May and early June 2008.

Scientific name Common name Number Collected

Family Ictaluridae Ictalurus furcatus Blue catfish 1337

I. punctatus Channel catfish 74 Pylodictis olivaris Flathead catfish 120

Family Mugilidae

Mugil cephalus Striped mullet 47 Family Atherinopsidae Menidia beryllina Inland silverside 2 Family Belonidae Strongylura marina Atlantic needlefish 5 Family Fundulidae Fundulus grandis Gulf killifish 2 Family Poeciliidae Gambusia affinis Mosquitofish 12 Heterandria Formosa Least killifish 7 Family Syngnathidae Syngnathus scovelli Gulf pipefish 1 Family Moronidae

Morone chrysops White bass 6 M. mississippiensis Yellow bass 2 M. saxatilis Striped bass 5 Family Centrarchidae

Chaenobryttus gulosus Warmouth 1 Lepomis humilis Orangespotted sunfish 4 L. macrochirus Bluegill 27

L. megalotis Longear sunfish 1 L. microlophus Redear sunfish 7

L. miniatus Redspotted sunfish 135 M. salmoides Largemouth bass 4 Pomoxis annularis White crappie 2

P. nigromaculatus Black crappie 2 Family Percidae Percina spp. Darter juvenile 1 Family Sciaenidae

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Aplodinotus grunniens Freshwater drum 29

Family Cichlidae Herichthys cyanoguttatus Rio Grande Cichlid 2

Family Gobiidae

Ctenogobius shufeldti Freshwater goby 3 Gobiosoma bosci Naked goby 2

Family Achiridae

Trinectes maculatus Hogchocker 1

Total Number of Individuals 2475

Total Number of Species 52 (excluding those only identified to family or genus

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Wastewater Source Detection and Correction in Tangipahoa Parish Bourgeois-Calvin, A. Lake Pontchartrain Basin Foundation, Metairie, LA. Introduction

The Tangipahoa River and Natalbany River watersheds encompass the majority of land area in Tangipahoa Parish. Land use was historically dominated by small rural towns to the south and dairy and agriculture to the north. In the past two decades cities have grown and sprawled while there has been a significant decrease in dairies (Tangipahoa Parish, 2008).

The Tangipahoa River and Natalbany River (including tributaries Ponchatoula Creek and Yellow Water River) are included on the Louisiana Department of Environmental Quality (LDEQ) 2006 Impaired Waterbodies (303d) List due to high fecal coliform levels (LDEQ, 2006). The fecal pollution derives from three sources: dairy farms and municipal and individual wastewater treatment plants (WWTPs).

The Lake Pontchartrain Basin Foundation (LPBF) began the Sub-Basin Pollution Source Tracking Program in January 2002 to track down and correct sources of fecal pollution in targeted sub-basins of the Lake Pontchartrain Basin. Activities of the program include intensive water quality monitoring, inspection of and assistance to WWTPs, statistical and GIS analysis of data, and public outreach/education in cooperation with state and local agencies (Bourgeois-Calvin, 2006). LPBF began implementing the program in the Tangipahoa and Natalbany Watersheds in 2005. Methods

Water Monitoring: Ten sites on the Tangipahoa River, 10 sites on Tangipahoa tributaries, and 10 sites within the Natalbany Watershed were monitored bi-weekly for the parameters of water temperature (ºC), pH, dissolved oxygen (mg/L), specific conductance (µS), and turbidity (NTU). For the fecal coliform and Escherichia coli analysis, one “grab” sample was taken at each site and analyzed at a laboratory (Bourgeois-Calvin, 2006a; APHA, 1998).

WWTP Assistance: LPBF, in partnership with the LDEQ’s Small Business Assistance Program, provided education, technical assistance, and assistance with permits to the owner/operators of WWTPs. The WWTPs were inspected for functionality and the paperwork and permitting of the plant was reviewed. The plant owners received assistance from LPBF and LDEQ to bring the plant into compliance. Results and Discussion

LBPF and LDEQ examined 117 WWTPs from January 2005 through June 2007. Most systems (75%) required some kind of assistance (yellow dots, Figure 1). 64% were not properly permitted for their discharge. In Louisiana, the Louisiana Department of Health and Hospitals (LDHH) permits WWTPs to be built according to the Louisiana Sanitary Code (LDHH, 2008). The LDEQ permits the plant to discharge into waters of the state, as part of the LPDES (Louisiana Pollutant Discharge Elimination System) program of the Clean Water Act (EPA, 2008). This system has led to a historic disconnect between these two agencies to where plants were routinely permitted to be built but not to discharge. Without having an LPDES permit the plants were not inspected and did not have their effluent tested for years to decades.

The most frequently encountered issue in regard to plant maintenance and functioning was the use of disinfection for the plant effluent. While the treatment process reduces the fecal bacteria count, it does not bring it to the low levels (< 400 MPN/ 100 ml water for a single sample) required by LDEQ. Of the plants assisted, 66% had the equipment to disinfect the effluent and 44% did not. Of the plants that could disinfect the effluent, only 61% of the plants were utilizing it correctly. Overall, 33% of the plants inspected correctly utilized disinfection for their effluent and 67% did not. In the permitting of plants to be built by LDHH, the plants are not required to have disinfection. LDEQ, through the LPDES program, requires disinfection (if needed) to discharge into waters of the state. So, plants that were not permitted by LDEQ most likely did not have disinfection for the wastewater effluent.

Technical assistance to the WWTPs occurred within the same time period as water quality data collection, allowing for fecal coliform and dissolved oxygen trends to be assessed over time. A linear regression line (black dotted line) was fit through the data to detect any general increasing or decreasing trends. The state water quality standard (red line) was also included on the graphs. For fecal coliform, the geometric mean of five

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samples was graphed for each date (each geometric mean including data from the two samples prior to the date listed, the date listed, and two samples after the date listed).

Sites on the Tangipahoa River had relatively consistent fecal coliform geometric means and dissolved oxygen levels throughout the time period. The river had low counts with spikes during rain events observed throughout the river (Figure 2). All Tangipahoa sites also exhibited consistent dissolved oxygen levels, all above 5 mg/l (the state standard) yet reducing slightly though the time period (Figure 3). In contrast, sites on Ponchatoula Creek (where WWTP assistance was concentrated) showed decreasing fecal coliform geometric means (Figures 4) and increasing dissolved oxygen trends (Figures 5) over time, indicating improving water quality with WWTP assistance.

Figure 1. WWTPs By Size and Compliance Status in the Tangipahoa and Natalbany Watersheds. The densest concentration of WWTPs occurred around the most urbanized areas and the majority of plants required assistance to come into compliance with LPDES permits.

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Site TR6- Fecal Coliform Geometric Means Over Time

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Figure 3. Tangipahoa River- Trend Over Time, Dissolved Oxygen (mg/l). DO was consistently high.

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Figure 4. Ponchatoula Creek- Trend Over Time, Fecal Coliform Geometric Means (MPN). Fecal coliform decreased over the period of data collection.

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Conclusion Utilizing wastewater plant data collected by the LPBF and LDEQ, it was found that the majority of the

plants assisted were not functioning properly and/or not permitted properly. This meant that they were discharging fecal bacteria into the surface water. As the assistance to the WWTPs was happening concurrent to data collection, fecal coliform and dissolved oxygen concentrations were evaluated over time to see if the WWTP assistance was having an impact on the waterbodies. While Tangipahoa River showed relatively stable trends over time, Ponchatoula Creek (specifically targeted for wastewater assistance) showed decreasing fecal coliform counts and increasing dissolved oxygen concentrations over the course of data collection.

The LPBF will continue to collect water quality data in the Tangipahoa and Natalbany Watersheds through 2010. LPBF will also continue working with state and parish entities to coordinate efforts within the watershed. The ultimate goal is to reduce fecal pollution loading in the waterbodies to meet the Clean Water Act’s “swimmable” criteria and get the waterbodies removed from the LDEQ’s 303(d) List.

References Cited American Public Health Association (APHA). 1998. Standard Methods for the Examination of Water and

Wastewater, 20th edition. Eds. Clesceri, L., Greenberg, A., and A. Eaton. APHA, Washington D.C. Bourgeois-Calvin, A. and B. Rogers. 2006. Fecal Pollution Source Tracking in the Tangipahoa/Natalbany

Watersheds. Proceedings from Basics of the Basin Eighth Biennial Research Symposium, October 25, 2006 New Orleans. pp 20-22.

Bourgeois-Calvin, A. 2006a. Sub-Basin Water Quality Analysis and Pollution Source Tracking (Tangipahoa

and Natalbany Watersheds). EPA Quality Assurance Project Plant Q-Track # 07-008.

Environmental Protection Agency. 2008. Introduction to the Clean Water Act.

http://www.epa.gov/watertrain/cwa/ Louisiana Department of Environmental Quality. 2006. 2006 Louisiana Water Quality Inventory: Integrated

Report. http://www.deq.louisiana.gov/portal/tabid/2692/Default.aspx Louisiana Department of Health and Hospitals. Accessed online 2008. Title 51: Public Health Sanitary Code,

Part XIII Sewage Disposal. http://www.dhh.louisiana.gov/offices/miscdocs/docs-206/SanitaryCode.pdf Tangipahoa Parish. Accessed online 2008. Tangipahoa Parish Comprehensive Plan.

http://www.tangiplanning.com.html

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Monitoring and Assessment of the 2008 Bonnet Carré Spillway Opening in Mississippi Sound, MS Burris, R., M. Brainard, M. Buchanan, M. Hill, and D. Diaz. Mississippi Department of Marine Resources, 1141 Bayview Ave. Biloxi, MS 39530

The U.S. Army Corps of Engineers opened the Bonnet Carré Spillway on Friday April 11, 2008 for the

eighth time since 1937. The spillway, which is located 28 miles north of New Orleans, Louisiana, was opened due to large amounts of rainfall in the Ohio Valley, as well as heavy snow melting in the upper Midwest, that subsequently entered the Mississippi River system. The spillway diverts fresh water from the Mississippi River through Lake Pontchartrain and eventually into the moderately saline waters of the Mississippi Sound. These prolonged periods of freshwater intrusion could have adverse affects on certain economically important organisms, such as oysters, finfish, shrimp, and crabs. High river flow by the Pearl River during this time period also contributed to the freshwater influence on the western Mississippi Sound’s hydrology, water quality, and species distribution. Separation of the influences between the Bonnet Carré and the Pearl River is practically impossible. Trawl samples were taken to evaluate finfish and invertebrate abundance from seven different locations in the western Mississippi Sound. Salinity, temperature, and dissolved oxygen values for surface and bottom water were measured concurrently with trawl samples. In addition to hydrological parameters, Chlorophyll a values and fecal coliform counts were determined from separate water samples taken at eight selected sites. Public oyster reefs were also sampled once a month to qualitatively assess oyster mortality relative to the opening of the spillway.

The Bonnet Carré spillway was operational for a total of 28 days and opened up to 160 gates at one time. The maximum amount of flow recorded during that time period was 160,000 CFS (Cubic Feet per Second) with an average of 113,000 CFS. Throughout the sample period water temperatures remained consistent with that of historical values. Average bottom and surface salinities were lowered during the months following the opening of the spillway. Little difference was seen between current and historical bottom dissolved oxygen values; however surface dissolved oxygen values were lower than historically recorded. Chlorophyll-a values increased during the month of May with values beginning to decrease in June. Fecal coliform concentrations remained low (<11 MPN) for the duration of the sample period. Oyster mortalities ranged from 0 to 33%; with the extremely high mortalities occurring prior to the spillway opening, and therefore not related. Trawl samples concluded that CPUE’s (Catch per Unit Effort) of blue crab (Calinectes sapidus), Atlantic croaker (Micropogonias undulates), and spot (Leiostomus xanthurus) fell within the range of historical variability. While brown shrimp (Farfantepenaeus aztecus), bay anchovy (Anchoa mitchelli), and sand seatrout (Cynoscion nebulosus) CPUE’s were found to be higher when compared to historical trends. Information from this assessment indicates that any impacts from the 2008 opening of the Bonnet Carré spillway were of short-term duration.

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Effect of the Opening of Bonnet Carré Spillway on Distribution of Heavy Metals in Lake Pontchartrain Ju Chou, Tian Tian, Garrett Clement, Terri Ilgen, Adriana Dantin Department of Chemistry and Physics Southeastern Louisiana University, Hammond, LA 70402 Bin Huang, Robert Gambrell Department of Oceanography and Coastal Sciences Louisiana State University, Baton Rouge, LA 70803

When the levees in New Orleans broke after Hurricane Katrina’s landfall, a great quantity of vehicles

pollutants, industry wastes, household chemicals, etc. were all dispersed into the flood water that poured back into Lake Pontchartrain. Ever since then, the lake has become an area of environmental concern. Early this year, large amounts of rainfall have caused water levels in the Mississippi River to rise, and to prevent the Mississippi River from flooding into surrounding areas, the Bonnet Carré Spillway was opened for the first time after 1997. The opening of the spillway is expected to lead to changes in nutrition and salinity in Lake Pontchartrain because of rush of fresh of water into the normally brackish lake. Because the Mississippi River is often polluted with agricultural runoff and factory discharge, historically, the opening of the spillway had lead to eutrophication in Lake Pontchartrain and the mass death of fish during the summer. Given the environment post-Katrina, the recent opening of the Bonnet Carré Spillway could also bring heavy metals--especially toxic metals--into the lake and in turn affect the lake's water quality and sediment chemistry. In this presentation, we will present how the opening of spillway affects the distribution of heavy metals in Lake Pontchartrain.

The levels of heavy metals, especially toxic metals and semimetals such as lead (Pb) and arsenic (As) were monitored before and after the opening of spillway. We collected surface and bottom water samples in Lake Pontchartrain. Sediments were also collected from the lake as shown in Figure 1. Water samples were filtered immediately after they were collected and were stored in a refrigerator. Heavy metals including toxic metals such as lead, arsenic and chromium in water samples were analyzed by an inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The ICP-AES is available at Dr. Gambrell’s laboratory at Louisiana State University (LSU). Sediments collected in the lake were dried at 107 ºC overnight in an oven. An acid extraction method was used to extract heavy metals (Pb, As, Cd, Cr, Cu, Zn, etc.) from sediments. Concentrations of heavy metals in sediments were also analyzed by ICP-AES at LSU. A distribution of heavy metals before and after the opening of spillway will be presented. Conductivities, pHs, concentrations of some nutrients such as Ca and Mg will be discussed before and after the opening of spillway. Lead contamination of the environment is primarily due to anthropogenic activities. Urban activities can contribute significantly to the accumulation of heavy metals in soils and sediments. Certain contaminant areas associated with human activities will be addressed.

Figure 1: Research Team was collecting sediments in Lake

Pontchartrain

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The implications of Hurricane Katrina and altered nutrient regimes on long-term trends in marsh elevation at Big Branch National Wildlife Refuge, Louisiana Reed, D.1, A. Commagere1, M. Hester2. University of New Orleans1. University of Louisiana Lafayette2

The tidal marsh habitats in Louisiana are threatened by sea level rise, increased frequency and intensity of tropical storms, as well as erosion and subsidence. These issues are potentially exacerbated by increased urbanization and development, which may lead to increased nutrient loading (Nicholls et al. 2007). The north shore of Lake Pontchartrain provides an excellent example of emergent wetlands threatened by such risks. In St. Tammany Parish alone, residential/urban land use increased over 159 % between 1982 and 2000 resulting in the conversion of 4.4 km2 of marsh to urban development (Beall et al. 2001). These marshes are essential for the valuable functions they provide, including water quality improvement, storm protection, and wildlife and fisheries habitat. Consequently, understanding the processes required to best manage them is critical. The results presented here resulted from the Pontchartrain Restoration Program study “Effects of Hurricane Disturbance on North Shore Marshes: Assessment of Resilience and Sustainability under Altered Nutrient Regimes.” The goal of the project was to identify the effects of hurricane impacts and nutrient input on an oligohaline marsh at Big Branch National Wildlife Refuge. Research plots had been established and monitored two years prior to hurricane Katrina, which allowed us to investigate the emergent wetlands’ response and resilience to hurricane impacts.

Surface elevation tables (SET) were used to measure changes in marsh elevation. Fifteen SETs were evenly distributed across three separate areas and within each area were randomly assigned a nutrient treatment. Nutrient treatments applied to SET plots included 40 g nitrogen m-2 yr-1, 30 g phosphorus m-2 yr-1, a combination of these levels of N and P, a lethal disturbance using Rodeo herbicide, and controls with no treatments. A baseline measurement was taken July 17, 2004 and subsequent measurements continued semi-annually until April 10, 2008. For analysis, the dataset was divided into pre-Katrina and post-Katrina subsets. The full time series was also analyzed for overall trends in rates of elevation change. Net change in elevation refers to the change in elevation relative to the initial measurement.

The pre-Katrina dataset exhibited significant positive rates of elevation change (i.e., the slope was significantly different from zero) for the control, combined N and P, and lethal plots (Table 1). Post-Katrina exhibited significant negative rates of elevation change for all treatments. However, the full time data set exhibited a significant positive rate of elevation change for all treatments except the N plots. A large increase in elevation occurred after hurricane Katrina in all treatment plots and was 2 to 8 times higher than the net change in elevation that occurred during the pre-Katrina time series (Figure 1). For example, in the control plot, from July 2004 to August 2005 there was a net change in elevation of 26 mm. From August 2005 to October 2005, there was a net change of 215 mm. Post-Katrina, a large decrease in elevation was evident, however, the elevation over the long term (July 2004 to April 2008) actually increased for all treatments, except for the N plots, which showed a slight decrease of 4 mm. Table 1. Rate of elevation change (mm/yr) pre-Katrina, Katrina, post-Katrina, and the full time series for each treatment. An asterisk indicates the slopes were not statically significant (p<.05). The Katrina time series was not statistically analyzed. Rate of elevation change (mm/yr)

Treatment Pre-Katrina (7/15/04 - 8/22/05)

Katrina (8/22/05 – 10/21/05)

Post-Katrina (10/21/05 – 4/10/08)

Full Time Series (7/15/04 – 4/10/08)

Control 22 1307 -49 50 P 5* 548 -31 29 N 11* 310 -36 1*

N+P 57 652 -43 39 Lethal 44 477 -39 31

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Examination of only the post-Katrina dataset suggests that marsh elevation is declining. On the contrary, analysis of the full time series reveals a positive increase in elevation relative to the initial measurement. Moreover, not only is the net change in elevation higher in April 2008 than immediately before the storm, the rate of elevation change for the control and phosphorus plots are actually higher over the long term than they were pre-Katrina (Table 1). These patterns of elevation change indicate substantial influence from Hurricane Katrina.

Figure 1. Change in elevation, relative to the initial measurement (7/15/04) for each treatment plot. Acknowledgements Thanks to Carol Wilson, Brendan Yuill and all those who aided in the collection of data over the years. This work was supported by NOAA grant #NA06NOS4630026.

References Cited Beall, A. D., S. Penland, and F. Cretini, Jr. 2001. Urbanization effects on habitat change in St. Tammany

Parish, 1982 – 2000. Final Report submitted to the Lake Pontchartrain Basin Foundation, Metairie, Louisiana. 19 pp.

Nicholls, R.J. and others. 2007. Coastal systems and low-lying areas. Climate Change 2007: Impacts,

Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the IPCC, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, 315-356.

Pre-Katrina Post-Katrina

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Determination of Optimal Burial Depth of Baccharis halimifolia (Groundsel Bush) Seeds for Maximum Germination and Emergence Dupuis, M.D. and M.W. Hester, Coastal Plant Ecology Laboratory, Department of Biology, University of Louisiana at Lafayette, Lafayette LA

Baccharis halimifolia L. is a perennial woody shrub native to Eastern North America that is a

component of many of the coastal plant communities throughout Louisiana including barrier islands. Barrier islands serve a key role in storm protection, as well as provide crucial habitat for wildlife. Therefore, efforts to restore degraded islands are vital to both economic and ecological stability in these coastal areas. One component of barrier island restoration is the rapid development of healthy plant communities because their root structure helps to maintain sediment stability and promote island integrity in addition to the habitat function provided by their aboveground structure. B. halimifolia is a pioneer shrub species, which is tolerant to salinity levels of up to approximately 12 ppt. The tendency of B. halimifolia to rapidly establish and its capacity to tolerate brackish salinities makes it an excellent candidate for restoration efforts on Louisiana barrier islands. Current (CWPPRA) value assessment models of barrier island restoration projects yield the greatest scores when two woody species are present in the restoration design template. Therefore, there is a need to develop cost-effective approaches for the establishment of key woody barrier island plant species. Black mangrove (Avicennia germinans) has been recognized as one such species for use in the upper backbarrier salt marsh habitat. B. halimifolia may be an ideal candidate species for use in the swale habitat for the reasons discussed below. Baccharis halimifolia, which can reach 16 feet in height, is a dioecious, evergreen shrub, in which the male flowers develop first in the mid fall followed by female flowers which develop in the mid to late fall. B. halimifolia is a prolific seed producer, with mature female shrubs producing 1.2 million seeds each fall. The seeds are wind dispersed, lack a dormancy period, and can germinate as soon as they disperse to a suitable site. Once established, B. halimifolia can quickly become a crucial component of these newly restored coastal habitats through its provision of woody habitat and sediment stabilization. However, planting seedlings is costly and labor intensive, so dispersing and establishing B. halimifolia by seed, especially in light of its prolific seed production output, may be an attractive alternative. Understanding what dispersal and germination conditions are optimal for B. halimifolia seedling emergence and establishment are important in the planning of any future restoration efforts. The objective of this experiment was to determine the optimal sediment burial depth at which B. halimifolia seed germination and seedling emergence is greatest.

Baccharis halimifolia seeds for this experiment were collected from a single female plant growing in coastal Louisiana. In this experiment, we assessed germination success and seedling emergence of seeds subjected to 5 burial depths. Each experimental unit contained 50 seeds placed in a treatment container of moist sand and buried to a depth of either 0, 0.5, 1.0, 2.0, or 3.0 cm. The experiment was completely replicated 6 times (30 experimental units, 1500 seeds total). Numbers of seeds germinated and emerged per treatment were counted every day for 2 weeks. Results indicate that B. halimifolia seeds have significantly greater combined germination and seedling emergence success when placed at or near the surface, whereas burial depths of 2 cm or greater inhibited germination and emergence success. This data corroborates results from previous experiments that suggest the need for light and temperature variation in B. halimifolia seed germination. Fluctuations in temperature by 7.5 C have been reported to increase germination by 25%, which when combined with exposure to light result in the greatest germination response. Our findings suggest that B. halimifolia seedling emergence success at barrier island restoration sites will likely be greatest when seeds are dispersed into swale habitats at the sand surface and not placed into furrows and covered. To reduce the probability of wind dispersal of seeds out of the targeted restoration area and excessive sand burial of seeds, we suggest that establishment success will be greatest when a modest amount of vegetative cover is present, possibly in combination with other wind-baffling mechanisms as needed, to provide sufficient substrate stability and low-deposition microsites for trapping seeds.

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The Development of a Coastal Education Program at the Coastal Education and Research Facility at Chef Pass Egger H. L., Maygarden, D.F., University of New Orleans, New Orleans LA

Recently the focus of the University of New Orleans-Pontchartrain Institute for Environmental Sciences

(UNO-PIES) Coastal Education Program begun to shift from providing wetland field trips around the Pontchartrain Basin to the development of a wetlands education program located at the Coastal Education and Research Facility (CERF) in the wetlands of eastern Orleans Parish. UNO’s Pontchartrain Institute for Environmental Sciences and the College of Sciences is currently in the process of developing this facility, located at Highway 90 and Chef Pass. This poster graphically describes the facility and our plans for its use in education.

A coastal education and research facility opens a wide range of possibilities and opportunities for residents of the Greater New Orleans area to learn about the coastal wetlands that serve to protect their homes and livelihoods. There are three main strands of opportunity that will develop with the facility: first, it will enhance the ability of UNO to offer quality field-based environmental science education at all levels, including to K-12 students, teachers, undergraduate and graduate students, and adults seeking increased knowledge base; second, it will greatly enhance the ability of UNO research scientists to carry out the vital task of data acquisition and analysis in order to understand our coastal dynamics and inform the coastal restoration, enhancement and protection process; third, by providing opportunities for college students to participate in field research, UNO will help train a workforce necessary to carry out the essential tasks of coastal management, restoration and protection in coastal Louisiana. The facility is located on the Eastern New Orleans Land Bridge, between Lake St. Catherine and Lake Pontchartrain and is identified by coastal managers as a critical line of defense for Lake Pontchartrain and greater New Orleans from storm surges. The wetlands of this area are mostly brackish marsh, with the exception of areas of wooded higher ground on the ridge that Highway 90 follows. There are excellent opportunities for access to these wetland areas for educational field trips and research. We are now waiting for the renovation to be complete so that we can begin operating at the CERF. Full operation is scheduled for early spring 2009.

The PIES Coastal Education Program plans to offer field trips to the facility for schools, professional development workshops for teachers, and coastal restoration focus workshops for community members. The Professional development workshops will provide opportunities for teachers to visit the facility, learn ways to incorporate wetlands issues into their curriculum and to develop a greater understanding of Louisiana’s coastal wetlands and strategies for coastal restoration.

A menu of three hands-on programs will be offered to teachers signing up their classes for field trips. Examples include: “Plants and Animals of the Coastal Wetlands”; “Protecting and Rebuilding our Coastal Lines of Defense”; and “Methods of Analyzing our Coastal Environments”. Some field trips will be land based, while others will be canoe and possibly motorboat based, depending upon boat availability. A wide variety of collecting equipment will be purchased for educational use. These will include wing, cast, seine, and dip nets for collecting organisms from the water; water quality equipment such as YSI meter and other instruments. One 50 gallon or two 25 gallon aquaria will be purchased and installed to display estuarine organisms caught at the dock and by the Nekton Research Lab (NRL) sampling equipment aboard their research vessel. The aquaria will be maintained with the help of NRL personnel.

The goal of the community workshops is to invite people from all walks of life who have an interest in the coastal wetlands and restoration process to gain a more intimate understanding of the topic. The intended outcome is for more people to become actively involved in the coastal restoration process and for a deeper understanding of the process to spread in the community. The community workshops will focus on the Eastern Orleans Land Bridge, which is a critical line of defense for the Lake Pontchartrain area when storm surges approach. The participants will visit the restoration projects in the area, including older CWPPRA projects and newer projects such as CIAP-funded projects to protect shoreline and restore marsh in this region. An anticipated outcome of these workshops is the identification and further training of people who wish to work in coastal restoration-related careers and activities.

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Response of barrier island fish assemblages to impacts from multiple hurricanes: assessing resilience of Chandeleur Island fish assemblages to hurricanes Ivan (2004) and Katrina (2005) M. Chad Ellinwood1, Martin T. O’Connell1, Christopher S. Schieble1. 1Nekton Research Lab, University of New Orleans, New Orleans, LA.

The impact of hurricanes in coastal regions may alter or destroy aquatic habitats resulting in long-term fish assemblage changes (Greenwood et al., 2006). The Chandeleur Islands, Louisiana, experienced major geomorphic changes and habitat loss during Hurricane Ivan which passed 150 km to the east of the islands on 16 September 2004 and Hurricane Katrina which passed 90 km to the west of the islands on 29 August 2005. Multiple surveys of the Chandeleur Islands ichthyofaunal assemblage were conducted from October 2003 to May 2008 at three habitat types; nearshore (seine), deep intertidal seagrass (gillnet), and demersal seagrass (trawl). Assemblage analysis procedures in the PRIMER-E® statistical package (Clarke and Warwick, 2001) were used to test for changes in fish assemblages over time. Specifically, an analysis of similarity (ANOSIM, α = 0.05) was used to determine significant differences among assemblages of similar months from different years. If significant differences were found among assemblages, a similarity percentage (SIMPER) analysis was used to determine which species contributed most to dissimilarities among assemblages and non-metric multidimensional scaling diagrams (MDS) were generated to show directional assemblage change movement.

During the ichthyofaunal survey a total of 49,971 fishes representing 100 species from 44 families were collected from three habitat types. From May 2004 to May 2008 pinfish (Lagodon rhomboides), the most abundant species collected during the survey, increased in abundance in nearshore habitats (497%) but decreased in abundance in demersal habitats (1,260%). This species was often the greatest contributor to dissimilarities between assemblages in nearshore and demersal habitats throughout the survey. Silver jenny (Eucinostomus gula), the second most abundant species collected during the survey, increased in abundance in nearshore and demersal habitats and was the second greatest contributor to dissimilarities between assemblages in those habitat types. Hardhead catfish (Ariopsis felis), the most abundant species collected in deep intertidal habitats, also increased in abundance throughout the survey. Water temperature, which is often the primary driver of assemblage change in relatively healthy ecosystems (representing typical seasonal changes), contributed most to assemblage changes in nearshore and demersal seagrass habitats (Spearman Correlation = 0.413 and 0.219, respectively) while in deep intertidal seagrass habitats a combination of water temperature and water depth contributed most to assemblage changes (Spearman Correlation = 0.34). If a fish assemblage is displaced or changes in composition over time, the point on an MDS plot representing that assemblage will move progressively further away from the original condition. However, fish assemblages may show “cyclicity” in multivariate space by returning to a similar point over some period of time (Mathews, 1998).

In nearshore habitats during May sampling at the Chandeleur Islands, a complex pattern of cyclic assemblage changes were seen at two sites while another appears to undergo a unidirectional pattern of assemblage change. Demersal and deep intertidal habitats also showed cyclic assemblage change movement during May sampling. Fish assemblages collected during other months showed patterns in directional assemblage change movements with most sites among similar months undergoing a similar direction of assemblage change movement. At the Chandeleur Islands, overall abundance and species richness increased in all habitat types during most months throughout the survey. The intermediate disturbance hypothesis states that because ecological communities seldom reach an equilibrium state, disturbances that kill or damage individuals set back the process of competition by opening space for colonization by less competitive individuals (Wilson, 1994; Townsend and Scarsbrook, 1997). Repeated local disturbance must occur at a rate not so frequent that most species are eliminated, yet frequent enough so that competitive exclusion does not occur over the whole area. This allows the coexistence of species with different life history strategies.

A decrease in overall abundance and species richness was observed in all habitat types during May 2006, the first sampling trip conducted following Hurricane Katrina. While habitat loss is generally recognized as the leading threat to biodiversity (Dobson et al., 1997), repeated disturbances to the Chandeleur Islands aquatic habitats within the last decade may be affecting the Islands’ ability to support a stable ecological assemblage. Overall, though, the fish assemblages from all habitat types at the Chandeleur Islands exhibited high resiliency to the impacts of these two major hurricanes.

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Reference Cited

Clarke, K. R. and R. M. Warwick. 2001. Changes in Marine Communities: An Approach to Statistical Analysis and Interpretation, 2nd ed., Plymouth, U.K. Dobson, A. P., A. D. Bradshaw and J. M. Baker. 1997. Hopes for the future: restoration ecology and conservation biology (in human-dominated ecosystems). Science 277(5325): 515-522. Greenwood, M. F. D., P. W. Stevens, and R. E. Matheson Jr. 2006. Effects of the 2004 hurricanes on the fish assemblages in two proximate southwest Florida estuaries: change in the context of interannual variability. Estuaries and Coasts 29(6A): 985-996. Mathews, W. J. 1998. Patterns in freshwater fish ecology. Kluwer Academic, Norwell, MA, 756p. Townsend, C. R. and M. R. Scarsbrook. 1997. The intermediate disturbance hypothesis, refugia, and biodiversity in streams. Limnology and Oceanography 42(5): 938-949. Wilson, J. B. 1994. The ‘intermediate disturbance hypothesis’ of species coexistence is based on patch dynamics. New Zealand Journal of Ecology 18(2): 176-181.

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Roles of seed source, site salinity and nursery practices on cypress sapling performance in restoration plantings in the LaBranche Wetlands bordering Lake Pontchartrain, Louisiana M. Farve1, T. Forman2 and J.L. Whitbeck1. 1 University of New Orleans, New Orleans, LA, and 2 Coalition to Restore Coastal Louisiana, Baton Rouge, LA.

Beginning in the late Winter of 2007, we established a field study comparing the survivorship and growth of cypress saplings reared from different seed sources in sites differing in tidal exposure. Our objective was to evaluate the relative importance of genetic (seed source) versus environmental (sites differing in tidal exposure and substrate salinity) influence on cypress sapling restoration success.

After one year less than 20 percent of the bare root saplings from the Louisiana Department of Agriculture and Forestry survived at our field sites, while 95 percent of our gallon pot-reared saplings survived. Survivorship of gallon pot-reared saplings was similar across field sites and among seed sources. Relative height growth of the saplings planted in late Winter 2007 varied across field sites. Height growth was greatest at our Milton’s Bridge (MB) site (Figure 1), where soil pore water salinity is consistently lower than at our other field sites.

LB #2LB #2a

LB #4LADA

w/treepro

LS

RS

PS

MB

0%

10%

20%

30%

40%

50%

60%

70%

80%

seed source

site

relative height growth March '07 - June '08

Figure 1. Relative height growth of saplings outplanted in March 2007. The three “LB” seed sources are parent trees located in the LaBranche Wetlands, while “LADA” refers to bare root saplings obtained from the Louisiana Department of Agriculture and Forestry.

Noting the poor survivorship of the bare root saplings we planted in Winter 2007, we decided to test the importance of pot – and root system – size during sapling rearing for subsequent field survivorship. Thus we raised seedlings from the same seed source in two different size pots, and we planted these saplings into our LaBranche Wetland field sites in Winter 2008, thereby establishing a test of pot size vs. seed source vs. field site salinity effects on cypress sapling establishment. We also added a site with only fresh water influence to our field trial. In addition to an updated report on the status of the 2007 planting, we will present early results from this expanded test of restoration conditions.

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Pontchartrain Basin Coastal Land and Marsh Vegetative Type Trends Fischer, M.R.1 and Padgett, W.C2. U. S. Geological Survey, National Wetlands Research Center, 1New Orleans, LA 2U.S. Army Engineer Research and Development Center, Environmental Laboratory, Vicksburg, MS.

The U.S. Geological Survey’s National Wetlands Research Center (NWRC) and its partners have been researching land loss in coastal Louisiana since the late 1970’s. The 2005 hurricanes spawned renewed interest in wetland loss in Louisiana and how that will affect communities in low-lying areas of the Bayou State. Barras et al. (2008) estimated that the Louisiana Deltaic Plain lost 2551.1 km2 (985 square miles) of land from 1956 to 2006, of which 217.6 km2 (84 square miles) were lost between 2004 and 2006. Within the Deltaic Plain, the Pontchartrain Basin (Planning Unit 1) lost approximately 145 km2 (56 square miles) between 2004 and 2006. Some of these areas may have begun recovering during the last few years. While Louisiana managed to get through the 2006 and the 2007 hurricane seasons unscathed, the 2008 hurricane season has delivered another blow to the Louisiana coastline. Hurricane Gustav pounded southeastern Louisiana with winds, waves, and storm surge. Recent photos depict many of Louisiana’s barrier islands in ruins. The Chandeleur Islands are the first lines of defense for the Pontchartrain Basin against tropical systems. Storms are major contributors to their existence and disappearance. The Chandeleur Islands were damaged by Hurricane Katrina in 2005 and again by Hurricane Gustav in 2008. Also, the majority of the coastal zone was recently impacted by Hurricane Ike, adding to the plant stress inflicted by the 2005 hurricanes. Although Ike made landfall in the Galveston/Houston area, the surge it unleashed on southwest Louisiana rivaled or exceeded that of Rita in 2005.

While scientists try to project what Louisiana could expect in the future (i.e. land loss/gain by 2050), the projected loss rates cannot account for such damaging episodic events. Previous land loss studies showed that the coastal Pontchartrain Basin net land loss rate was 570 km2 (220 square miles) for the 1956 - 2000 time period (5 square miles per year). The National Wetlands Research Center also conducted a study to support the Louisiana Coastal Area Ecosystem Restoration Study, which indicates that an additional 158 km2 (61 square miles) may be lost from 2000 to 2050. However, the Barras et al. (2008) study indicates that the Pontchartrain basin area has a net loss of 161 km2 (62 square miles) between 2001 and 2006. Scientists are just learning how destructive tropical systems can be to the coastal marshes and what a critical role they play in the change of Louisiana’s coastal landscape.

In addition to land change studies, U. S. Geological Survey, the Louisiana Department of Wildlife and Fisheries, and Louisiana State University are documenting the salinity changes in Pontchartrain Basin by observing the trends in coastal marsh vegetation types between 1949 and 2007. All data sets contain vector information of visual field observations taken from a helicopter. Flights were along north/south transects spaced 1.87 miles apart and vegetative data was obtained at pre-determined stations spaced at 0.5 miles along each transect. This information was recorded manually into field tally sheets and later entered into a database. A GIS application was then used to delineate marsh type boundaries by digitizing contours through on-screen interpretation. The results will show how the vegetation type has changed over the years and provide insight into trends influencing habitat change. As the barrier islands and Gulf-most coastal marshes deteriorate, salinities will rise in the interior marshes due to salt water intrusion and other factors. Louisiana may continue to see fresh, intermediate, and brackish marshes convert into more saline marsh (see Figure 1).

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Marsh Vegetative Type in Pontchartrain Basin1949 to 2007

0

10

20

30

40

50

60

1949 1968 1978 1988 1997 2001 2007

Year

Perc

ent (

%) Fresh marsh

Intermediate marshBrackish marshSaline marsh

Figure 1: Marsh vegetation type in the Pontchartrain Basin 1949 to 2007

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Disturbed: A 15 Year Profile of Hurricanes, Drought, Flood and Fire in the Resilient Pearl River, Louisiana Ecosystem Ford, Mark A. GEC, Inc., Baton Rouge, LA 70809

The lower Pearl River coastal ecosystem in Louisiana is primarily a state wildlife management area. In spite of minimal human modifications to this area, relative to the rest of the Louisiana coast, its proximity to the Gulf of Mexico leaves it exposed to major tropical storms and hurricanes. Being a relatively small watershed, compared to the neighboring Mississippi River basin, localized heavy rain events often lead to floods which exceed normal tidal ranges. Fires, drought, wrack deposits and major herbivory events contribute to a continuing set of disturbance events that shape this coastal ecosystem.

Fifteen years of soil elevation (SET) data have been collected in the lower Pearl River basin. Though initially established to determine herbivory impacts on soil elevation changes (Ford and Grace, 1998 a,b), 10 sites have been monitored over the past 13 years to document longer-term changes. Erosion at the river’s edge has claimed roughly one meter of linear land moving inward. Shallow subsidence was measured during the first year of the study at 2.26 cm/year; however, vertical soil accretion outpaced subsidence during that same time period at an average of 2.48 cm/year. Overall soil elevation increase was, therefore, 0.22 cm/year for the first year of the study. Feldspar maker horizons, used to measure sedimentation, subsided quickly and were not recoverable after 3 years.

Over the entire 15 years of the study, several major hurricanes have either directly hit(e.g., Hurricane Katrina) or influenced flooding, sediment deposits, or erosion of the soil surface from near misses. Periodic non-tropical system floods have also produced dramatic effects, depositing as much as a centimeter of sediment over a short period of time. One such flood was the May 1995 flood during which 6 hour rain-fall amounts averaged 12 inches. During the ‘brown marsh’ drought period from early 1999 to mid 2001, soil elevation decreased by 1.4 cm in only one year, but quickly rebounded and returned to near pre-event levels within a year of the end of drought conditions. Hurricane Katrina passed directly over the study area in 2005, resulting in a combination of erosion and sediment deposition, which resulted in roughly a 4 cm increase in soil elevation. During the study period, extreme herbivore events, or eatouts, and periodic fires have contributed to a changing landscape. Feral hogs and nutria have consumed acres of plants in very short periods of time, and dug up soils while foraging on roots and rhizomes leaving large patches of marsh appearing tilled and void of standing plants. Two wildfires occurred, which removed roughly half of the standing vegetation in one event and virtually all in a second event. The plant community has undergone changes over time as well. A several acre area of hog cane, Spartinia cynosuroides disappeared within one year between 2002 and 2003. Still, in spite of all disturbances of varying magnitudes, the Pearl River wetlands, near the mouth of the river, have shown an overall increase in elevation over the past 15 years. This increase indicates that this coastal ecosystem, which, unlike most of coastal Louisiana, and is largely void of man-made canals and levees, is not only very dynamic and ever changing, but also able to maintain its elevation in the face of rising sea level and disturbances that are common to the Gulf of Mexico wetlands.

References Cited Ford, M.A., and J.B. Grace. 1998a. Effects of vertebrate herbivores on soil processes, plant biomass, litter accumulation and soil elevation changes in a coastal marsh. Journal of Ecology 86:974-982. Ford, M.A., and J.B. Grace. 1998b. The interactive effects of fire and vertebrate herbivory on a coastal marsh in Louisiana. Wetlands 18:1-8.

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The effect of hypoxia on habitat selection of juvenile estuarine fishes John Froeschke and Gregory W. Stunz, Harte Research Institute for Gulf of Mexico Studies, Texas A&M University-Corpus Christi.

Hypoxic events where dissolved oxygen concentrations fall below 2 mg/l are becoming a wide-ranging phenomenon. However, there has been little research on the biological effects of hypoxia, especially the potential impact on habitat selection of juvenile fishes. We designed a series of mesocosm experiments to assess the relative influence of hypoxia and seagrass on habitat selection for three common estuarine species, Atlantic croaker (Micropogonias undulatus), pinfish (Lagodon rhomboides), and red drum (Sciaenops ocellatus). Experiments were conducted using a large mesocosm where a dissolved oxygen gradient was established. Artificial seagrass units (ASU’s) and sand were used as habitat treatments. All three species could detect and respond to both the oxygen concentration and habitat treatments. The response between the habitat and oxygen concentration was hierarchical and interactive. In conditions where oxygen concentrations were <2 mg/l, fishes chose the region with the greatest oxygen concentration.. However, at moderate levels of hypoxia (4 mg/l), habitat selection was primarily influenced by availability of the preferred habitat. Results indicate that hypoxic events may strongly affect habitat selection of juvenile fishes and this may alter subsequent distribution patterns and biological interactions within estuarine communities.

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Hydrodynamic and Salinity Modeling of Mississippi River Diversion Flows: Violet, Louisiana Georgiou, I.Y.1, McCorquodale, J.A.1, Retana, J. Schindler, A.G.1,2, FitzGerald, D.M.3, Hughes, Z.3 University of New Orleans (PIES and FMI Center for Environmental Modeling),2 Brown and Caldwell, 3 Boston University.

The focus of this study was the response of salinity in Lake Borgne, the Biloxi Marshes and Mississippi, Chandeleur and Breton Sounds of the Pontchartrain Estuary, in response to freshwater diversions from the Mississippi River at Violet. Diversions in the range of 5,000 to 15,000 cubic feet per second (cfs) were investigated using an unstructured 3D Finite Volume Coastal Ocean Model. Model runs simulated discharge conditions throughout the year with representative tides and tributary flows. The spring period corresponds to the time when the Mississippi River is at its maximum annual stage, thus providing the greatest potential hydraulic gradient and highest flow through a given structure. A reference condition representing existing conditions with no diversion was compared to diversion flows of 5,000, 10,000 and 15,000 cfs initially. Additional simulations using run-of-the-River hydrographs, and the inclusion of multiple diversions in the upper estuary from authorized and proposed diversions were also included in the simulation matrix. In all of the diversion scenarios, the MRGO channel was constricted by approximately 90% at a location near Bayou La Loutre.

Model simulations show that salt water inflow along the diversion channel and into Lake Borgne was significantly reduced when MRGO is constricted. Larger diversions in the range of 10,000 to 15,000 cfs were effective in lowering the mean salinity in the Biloxi Marsh area by 3 to 5 ppt after 60 days of the effective flow diversion. The influx of freshwater via the Violet Canal shifted the mean 10 and 15 ppt isohalines towards the Gulf of Mexico by approximately 10 - 12 miles (16-20 km). The model indicates that the salinity reduction at the north entrance of the Biloxi Marshes begin in as little as one month after the diversion is initiated. The model results indicate that modification of the MRGO and the introduction of freshwater at Violet can significantly change the present salinity regime in Lake Borgne and eastern Lake Pontchartrain.

The first series of simulations was completed to determine the system response to a 2 month diversion at Violet. This period was the period that was expected to result in a change in salinity in the vicinity of the Biloxi Marshes for diversion flows of the order 10,000 to 15,000 cfs. The model showed that target salinities could be met within 2 months with a diversion in the range of 10,000 to 15,000 cfs. It also appears from the model that the diversion flow reduces the mixing of the Pearl River Plume with highly saline water; as a result even after one month there is a significant salinity reduction in Lake Borgne. The response time for salinity reductions at the Biloxi Marshes is faster than the theoretical fill times would suggest. These simulations indicate that it will take approximately one month before a change in the diversion flow at Violet produces a change in the salinity at the Biloxi Marshes. The next series of simulations was completed to determine the long term response of the Estuary to annual diversions at Violet. The diversion flows varied seasonally according to the mean monthly stage available in the Mississippi River. The two operational hydrographs were assumed to have peak monthly flows of 5,000 and 15,000 cfs (March-April) and minimum monthly flows of 2,000 and 650 cfs (Fall) respectively. The simulation period of 12 months permitted estimates on the effect of various Violet diversion options on the salinity in Lakes Pontchartrain and Borgne in addition to the Biloxi Marshes. The extended simulations showed that solely reducing the cross-section of a portion of the MRGO could reduce the system salinity over a 12 month diversion by approximately 20% in eastern Lake Pontchartrain, Lake Borgne and the Biloxi Marshes compared to the existing conditions with no restriction in the MRGO.

Finally, recent results from multiple diversion simulations in the upper estuary show that with additional freshwater input from other sources in the upper estuary, the required diversion flows at Violet, that are needed to meet salinity objectives, can be reduced. All simulations presented included actual tidal conditions and natural freshwater inputs. The 10 ppt and the 15 ppt isohalines represent a mean position for the spring period; however, wind effects and Gulf of Mexico fluctuations have not been modeled and could result in large transient translations of the isohalines. This will generally alternate between upstream and seaward movement with respect to a given mean isohaline. These oscillations, along with the inclusion of additional dispersion due to both remote (Gulf of Mexico) and local forcing could result in isohaline spatial translations of the order ± 2.5 ppt or ± 4 km. The effect of more frequent tropical storms was not addressed in this study.

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Factors Affecting Water Quality In Lake Madeline (Galveston, Texas): Implications For Design Of Waterfront Communities Guillen, George., Jenny Wrast and Dianna Ramirez. University of Houston Clear Lake, Environmental Institute of Houston, 2700 Bay Area Blvd, Houston, Texas 77058. [email protected] 281-283-3950

Many coastal waters along the Gulf of Mexico are threatened by poor water quality due to a contamination by improperly treated wastewater and associated waterborne pathogens. Due to ongoing concerns about potential risks associated with exposure to sewage contaminated water and reoccurring fish kills, a study was conducted during the summers of 2006 and 2008 on an enclosed canal subdivision, Lake Madeline, which is located in Galveston, Texas. The first objective of this study was to delineate the distribution, levels, and origin of bacteriological indicators in the watershed and to determine factors that may contribute to these increased levels. This included evaluation of indicator bacteria levels before and after implementation of rehabilitation of sewer systems. The second objective was to characterize trends in dissolved oxygen before and after implementation of mitigation measures.

The data collected during this study and past investigations supports the hypothesis that failing wastewater collection systems and associated contaminated storm water runoff are a significant source of indicator bacteria within coastal communities. Limited tidal mixing, salinity stratification, and organic loading contributed to hypoxia or anoxia and high levels of bacteriological indicators and associated pathogens. This scenario is common in many older coastal developments of this type. To avoid similar problems in the future subdivisions need to incorporate designs and strategies that promote mixing and reduce loading of pathogens and organic material including appropriate basin and canal design and limitations on point source and storm water discharges.

References EPA (U.S. Environmental Protection Agency) 1985. Coastal marinas assessment handbook. U.S. EPA.

Region IV. Atlanta, Georgia.

EPA (U.S. Environmental Protection Agency) 2001. National Management Measures to Control Nonpoint Source Pollution from Marinas and Recreational Boating. EPA 841-B-01-005, November 2001. Washington, D.C.

EPA (U.S. Environmental Protection Agency) 2003. Shipshape shore and waters: a handbook for marina operators and recreational boaters. EPA-841-B-03-001, January 2003. Washington, D.C.

Fields, S. 2003. The environmental pains of pleasure boating. Environmental Health Perspectives. 111: A216-A223.

Floerl, O and G. Inglis 2003. Boat harbour design can exacerbate hull fouling. Austral Ecology. 28:116–127.

Guillen, G.J., S. Smith, L. Broach, and M. Ruckman. 1993. The impacts of marinas on the water quality of Galveston Bay. pp. 33-46. In: Proceedings of the 2nd State of the Bay Symposium. Galveston Bay Estuary Program. GBNEP 23. Webster, Texas.

Hollin, D., J. Massey, J. Jacob and G. Treece. 1998. Airing out the problem: Methods of reducing water quality impacts of fish kills in coastal marinas. TAMUG-SG-98-503. Texas Sea Grant Program. College Station, Texas.

Hollin, D. 2004. Texas recreational boating facilities database. Texas A&M Sea Grant College Program. Texas A&M University. College Station, Texas.Lowe, J.A., D.R.G., Farrow, A.S. Pait, S.J. Arenstam, and E.F. Lavan. 1991. Fish kills in coastal waters 1980-1989. NOAA. Rockville, MD.

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McElyea, B. 2003. A comparison between fecal coliform, E. coli, and Enterococci, as bacterial

indicators in southeast Texas Surface Waters. AS-189. TCEQ. Houston, Texas.

Milliken, A. and V. Lee. 1990. Pollution impacts from recreational boating. RIU-G-90-002. Rhode Island Sea Grant. Narragansett, RI.

Nixon, S., C. Oviatt, and S. Northby. 1973. Ecology of small boat marinas. Marine Technical Report Series No. 5. RIU-T-73-004. University of Rhode Island. Kingston, R.I.

Trent, W., E. Pullen and D. Moore. 1972. Waterfront housing developments: their effect on the ecology of a Texas Estuarine area. Page 1-7 in: Marine Pollution and Sea Life. Fishing News Ltd. West Byfleet, Surrey.

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Population Status And Demographics Of The Diamondback Terrapin In West Bay (Galveston Bay, Texas) Haskett, Kelli. 1, and George Guillen1 1University of Houston Clear Lake, Environmental Institute of Houston, 2700 Bay Area Blvd, Houston, Texas 77058. 281-283-3950. [email protected]

A growing concern for the Galveston Bay region has been the status of the Texas diamondback terrapin (Malaclemys terrapin littoralis). This small reptile is the only turtle species to live exclusively in brackish water. Their numbers have been declining since the late 1800’s when commercial harvesting began. Their flesh was considered a delicacy and as a result of intensive harvesting their populations appeared to rapidly decline. Today, they appear to be threatened by coastal development, pollution, automobiles, and commercial crab traps.

The reduction in numbers of this important species may have caused detrimental impacts to the local environment in which they live. These reptiles represent top-level predators that regulate estuarine food webs. Due to declining population levels of diamondback terrapin within the United States, they are currently listed as an endangered species in Rhode Island and a threatened species in the state of Massachusetts. Although not protected, they are considered a “species of concern” in Georgia, Delaware, Louisiana, and North Carolina. The current population level of the Texas diamondback terrapin is unknown but believed to be depressed. Little information has been gathered on the numbers and life history traits of this local population. Currently the diamondback terrapin is not a protected species in the state of Texas.

The geographic focus of our study has been areas where terrapin have been previously observed or collected. Based on historical data a comprehensive study of the Texas diamondback terrapin population in West Bay, Galveston, Texas was initiated in November 2007. The primary objectives of our study were to determine current terrapin abundance, short-term movement, and potential crab trap bycatch mortality in portions of the Galveston Bay system. In less than one year, over 100 individual terrapin have been caught on North and South Deer Islands. Three have been fitted with a radio transmitter to track their movements within and around the islands and more will be fitted with these devices in the near future. Acoustic receivers have also been deployed around the islands to aid in tracking the movement of these reptiles.

Determining current population numbers is necessary for determining the threat of extinction. It is essential to know if the population of Texas diamondback terrapins is sufficiently large and will remain viable under current levels of environmental disturbances. Radio tracking data collected will aide in determining movement and home ranges of these animals. A combination of several techniques including trap catch per unit effort, mark recapture population estimates, and radiotelemetry will help to answer these questions. These techniques have generated preliminary data that can be used to determine whether these turtles are likely to rebound in the event of local extirpation. Future research is needed in other portions of Galveston Bay and the Texas Coast in order to attain a more comprehensive assessment of the population.

References Baker, P.J., Costanzo, J.P., Herlands, R., Wood, R.C., Lee, R.E., Jr. Inoculative freezing promotes

winter survival in hatchling diamondback terrapin, Malaclemys terrapin. Canadian Journal of Zoology. 2006;84:116-124. Boarman, W.I., Goodlett, T., Goodlet, G., Hamilton, P. Review of Radio Transmitter Attachment Techniques for Turtle Research and Recommendations for Improvement. Herpetological Review. 1998; 29(1): 26-33. Bossero, M., Draud, M. Diamondbacks at water’s edge. New York State Conservationist. 2004; 59(2):6-9. Brennessel, B. Diamonds in the Marsh: A Natural History of the Diamondback Terrapin. New Hampshire: University Press of New England; 2006. Burke, R.L., Schneider C.M., Dolinger M.T. Cues used by raccoons to find turtle nests: effects of flags, human scent, and diamond-backed terrapin sign. Journal of Herpetology. 2005; 39(2):312-315.

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Garber, S.D. Diamondback terrapin. Focus. 1990; 40(1): 33-36. Garton, E.O., Wisdom M.J., Leban, F.A., Johnson, B.K. Radio Tracking and Animal Populations: Experimental Design for Radiotelemetry Studies. San Diego: Academic Press; 2001. Gibbons, J.W., Andrews, K.M. PIT tagging: simple technology at its best. Bioscience. 2004; 54(5): 447-454. Hauswald, J.S., Glenn, T.C. Population genetics of the diamondback terrapin (Malaclemys terrapin). Molecular Ecology. 2005; 14: 723-732. Hogan, J.L. Occurrence of the diamondback terrapin (Malaclemys terrapin littoralis) at South Deer Island in Galveston Bay, Texas, April 2001-May 2002. U.S. Geological Survey. 2002; 1-23. Krebs, C.J. Ecological Methodology. Addison-Wesley Educational Publishers; 1999. Mitro, M.G. Demography and viability analyses of a diamondback terrapin population. Canadian Journal of Zoology. 2003; 81: 716-726. Neubaum, D.J., Neubaum, M.A. Ellison, L.E., O’shea, T.J. Survival and condition of big brown bats (Eptesicus fuscus) after radiotagging. Journal of Mammalogy. 2005; 86(1):95-98. Texas diamondback terrapin (Malaclemys terrapin littoralis). Texas Parks and Wildlife web site. 2007. Available at: http://www.tpwd.state.tx.us/huntwild/wild/species/terrapin/. Accessed January 28, 2007.

Tucker, A.D., Gibbons, J.W., Greene, J.L. Estimates of adult survival and migration for diamondback terrapins: conservation insight from local extirpation within a metapopulation. Canadian Journal of Zoology. 2001; 79:2199-2209.

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Status and Trends of the Bucktown Created Marsh: A Southshore Success Story? Hester, M.W., J.M. Willis, Coastal Plant Ecology Laboratory, Department of Biology, University of Louisiana at Lafayette, Lafayette, LA.

The Bucktown area mitigation marsh was constructed in the summer of 2000. This marsh is located immediately outside the Lake Pontchartrain levee in the greater “Bucktown” area of Jefferson Parish, just west of the Orleans Parish line (17th Street Canal) and the US Coast Guard station (Figure 1). This mesohaline marsh was designed and created with a target area of 3.5 acres and an elevation of 1.5 to 2.0 NGVD using hydraulic dredging. Material for the construction was dredged from the adjacent Bucktown Harbor and allowed to settle and consolidate for approximately two years prior to the initiation of planting. Contractors completed planting 1,030 trade gallons and 8,000 vegetative plugs of salt-hardened Spartina alterniflora (Vermillion accession smooth cordgrass) in August 2003. The Lake shoreline and levee area immediately surrounding the created wetland are utilized extensively for outdoor fitness activities by the local population (e.g., walking, jogging, biking, horseback riding, dog walking). In the summer of 2005, my lab conducted an initial gratis characterization of the vegetative community, elevation, and basic sediment biogeochemistry. This was generously supplemented by funds from the Lake Pontchartrain Basin Foundation in 2006 and 2007 to established permanent sampling plots and elevation benchmarks to continue our research efforts. Twenty (20) 1.0-m2 permanent plots were established on June 30, 2006 throughout the Bucktown created marsh site, with 5 replicate plots being established in each of four habitat types (Figure 2). Habitat types consist of western low marsh, high marsh, scrub-shrub, and eastern low marsh. Two SETs (sediment elevation tables), one in low marsh and one in scrub-shrub, were also established.

Results to date indicate that the transplanted salt marsh dominant Spartina alterniflora (smooth cordgrass) has done well and thrived in both the eastern and western low marsh zones where it has been, and continues to be, the dominant plant species. As indicated by the zone description, these zones are lower in elevation and subject to tidal fluctuations, which is the preferred habitat for smooth cordgrass. Nonetheless, all zones have displayed fairly high values of total (community) vegetative cover with varying species compositions both spatially and temporally. Smooth cordgrass remains an important, but less dominant, species in the high marsh with Paspalum spp. and Schoenoplectus americanus. Of these, Schoenoplectus americanus has increased steadily in cover during the study, although Iva frutescens (marsh elder) has become a more conspicuous component of the high marsh plant community. In the scrub-shrub zone, elevation is highest, as is soil bulk density; soil organic matter is correspondingly lower. In this zone Iva frutescens has remained a co-dominant or dominant plant species throughout the study. Pluchea camphorata (camphor weed) was initially widespread in this zone, but has decreased in prevalence and cover as marsh elder has increased.

To date, this created marsh has survived hurricane impacts well with minimal impact to the plant communities. Marsh zones in the intertidal continue to accrete sediment, and the smooth cordgrass is very robust. The futures of the higher zones, especially the scrub-shrub zone, are less clear. Although marsh elder can provide bird nesting habitat, shading from too dense a canopy may adversely affect species diversity and possibly marsh resilience in the future, should a strong and saline storm surge occur. Continued monitoring will elucidate vegetation and elevation trajectories for improved marsh restoration and management success in the Basin.

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Figure 1: Location of the Bucktown Marsh on the south shore of Lake Pontchartrain

Figure 2 Study site with plot habitat types identified in above legend. Numbers correspond to plot numbers. Image source is Google earth accessed March 17, 2008.

Bucktown Marsh Creation Area

US Coast Guard Station

Western Low Marsh

High Marsh

Scrub Shrub

Eastern Low Marsh

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The physics of episodic hypoxia in Corpus Christi Bay Hodges, B.R., Center for Research in Water Resources, University of Texas at Austin. [email protected]

Despite its shallowness (~ 4 m depth) and strong consistent summer winds (~ 6 m/s), Corpus Christi Bay (CC Bay) has experienced episodic summer stratification and hypoxia for at least the past two decades (Montagna and Ritter, 2006). Until recently the physical causes of this stratification were not clear. Our studies indicate that stratification may result from hypersaline density currents originating in adjacent bays. The Laguna Madre (which connects to CC Bay through the Gulf Intracoastal Waterway and shallow flats) has summertime salinities in high residence-time areas that can exceed 50 ppt, resulting in significantly higher densities than the CC Bay ambient. This Laguna Madre water is also introduced into Oso Bay through the Barney Davis Power Plant cooling water system, resulting in a second (smaller) hypersaline water body adjacent to CC Bay. A 48-hour intensive field study at the nexus of Oso Bay and CC Bay revealed a thin-layer (~ 30 cm) hypersaline gravity current that is initiated with saturated DO and is reduced to hypoxic about 2 km out into CC Bay over a propagation time of 12 hours (Figure 1). The implied DO consumption rate is consistent with measured SOD of Sell and Morse (2006) for CC Bay. The plume out of Oso Bay appears to be tidally moderated, initiating the plume on ebb tides and shutting down the hypersaline water supply on flood tides.

Figure 1. Contours of temperature, salinity and dissolved oxygen recorded over ~2 hour sampling times during the Oso Bay experiment.

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A second study in the southeast corner of CC Bay near the Laguna Madre discovered a thicker plume (~1.5 m) that appears to originate during stronger sustained wind events, which dislodge the hypersaline water from the shallows of the Laguna Madre and introduce it into CC Bay. Although our studies need further expansion for confirmation and to quantify the extent of these effects, we hypothesize that the episodic hypoxia in the southeast corner of CC Bay is not tidally-moderated, but is instead event-moderated. Strong winds provide a large slug of hypersaline water that spreads along the bottom over a period of several days. The size of the hypersaline slug is limited by the storage in the Laguna Madre shallows, which are likely replenished by less saline Gulf Intracoastal Waterway (GIWW) water (possibly re-circulated from CC Bay) during the wind event. Once the Laguna Madre shallows have salinities similar to CC Bay, the density current slug is pinched off. The residence time in Laguna Madre shallows to renew hypersalinity (via evaporation) and repeat these events is not yet known. A simple plot of DO vs. salinity anomaly (Figure 2) does not show any correlation between the strength of stratification and hypoxia. Figure 2 is strikingly similar to Figure 10 in Engle et al. (1999), where data from all available northern Gulf of Mexico estuaries were analyzed in a similar manner. We have shown (Hodges et al, 2008) that the wide scatter of Figure 2 cannot be interpreted as the unimportance of stratification in the development of hypoxia. Quite the contrary, the strength of the salinity anomaly is simply a poor proxy for the real problem: the isolation time (due to stratification) of benthic water over sediments significant oxygen demand. Because the system is non-stationary such that the wind is continually mixing and eroding the stratification, the largest salinity anomalies occur when the hypersaline

Figure 2. Measured bottom water dissolved oxygen (DO) against the bottom to surface water salinity anomaly (psu ~ ppt) for all locations in a hypersaline density plume flowing out of Oso Bay. water is initially plunging under CC Bay ambient water. After this initial plunge, the under-flowing water has the shortest isolation time, the highest DO concentration (in some cases supersaturated) and the largest salinity anomaly. As the density current flows along the bottom of the bay (i.e. increasing isolation time), physical processes of entrainment, wind mixing and current shear progressively weaken the salinity anomaly. Hypoxia occurs when the turbulent mixing processes cannot supply sufficient DO from the ambient to keep up with DO demand in the isolated benthic water and sediment. Because it takes time for these demands to reduce the

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original plume DO from the hypersaline source water, perversely the hypoxia occurs predominantly in the weaker (but non-zero) salinity anomalies. Thus, isolation time is a much better proxy for the effect of stratification than the salinity anomaly, and the lack of correlation shown in Figure 2 cannot be interpreted as evidence that stratification is unimportant or that some other process (other than stratification) is controlling. Unfortunately, isolation time cannot be directly or simply measured, but must be analyzed through detailed field studies and/or modeling of the physics surrounding the development and destruction of stratification.

References Cited Engle, V. D., Summers, J. K., and Macauley, J. M. (1999). “Dissolved Oxygen Conditions in Northern Gulf of Mexico Estuaries.” Environmental Monitoring and Assessment, 57(1), 1-20. Hodges, B.R., J.E. Furnans and P.S. Kulis, (2008) “A thin-layer gravity current and hypoxia in Corpus Christi Bay,” submitted to Journal of Hydraulic Engineering. Montagna, P. A. and Ritter, C. (2006). “Direct and Indirect Effects of Hypoxia on Benthos in Corpus Christi Bay, Texas, USA.” Journal of Experimental Marine Biology and Ecology, 330(1), 119-131. Sell, K. S. and Morse, J. W. (2006). “Dissolved Fe2+ and ΣH2S Behavior in Sediments Seasonally Overlain by Hypoxic-to-Anoxic Waters as Determined by CSV Microelectrodes.” Aquatic Geochemistry, 12(2), 179-198.

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The interaction of salinity, low dissolved oxygen and blue crab predation on Rangia clam survival

Howard, A.C., Spalding, E.A., Walker, A.E., and M.A. Poirrier. Department of Biological Sciences, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148.

Dissolved oxygen concentrations less than 2 mg/L (hypoxia) are a problem in estuaries worldwide. Lake Pontchartrain, located north of New Orleans, Louisiana, is a large, shallow, estuarine embayment with an average water depth of 3.7 meters, a mean salinity of about 4 ppt and a surface area of 1631 km2. High salinity water from the Gulf of Mexico enters the lake through the Inner Harbor Navigation Canal via the Mississippi River Gulf Outlet, resulting in stratification which gives rise to an approximately 250 km2 hypoxic zone. Within this zone, mature Rangia cuneata (Bivalvia: Mactridae) > 20 mm are absent. In addition to being an important food source of fish, crabs, and waterfowl, Rangia population density and size of individuals are important indicators of lake health and water quality. Salinity stress, hypoxic conditions, and predation may explain the lack of mature clams.

To determine the acute effects of salinity and hypoxia on Rangia clam survival, clams were subjected to four salinity shifts from 5 ppt to 0.1, 10, 15, and 20 ppt and then exposed to environmental hypoxia for varying lengths of time. Under normoxic conditions, clams survived for at least seven days at salinities of 1 ppt, but only an average of 3.5 days at 0.1 ppt. After the time to death at different salinities was determined, clams were subjected to hypoxic conditions and then subjected to the four salinity shifts. Hypoxic exposure times were 0 hours, 24 hours, 48 hours, 72 hours, and 120 hours (or until death). The combined effect of salinity stress and low dissolved oxygen concentrations decreased Rangia survival when compared to the control, especially at low salinities (0.1, 1.0, and 5.0 ppt) and 20 ppt. The highest survival (at least 7 days) occurred at 10 ppt under 72 of hypoxic conditions and 15 ppt under 24 hours of hypoxia.

A major predator of Rangia clams in Lake Pontchartrain is the blue crab (Callinectes sapidus). Blue crab predation influences the distribution and abundance of benthic organisms. Because blue crabs are mobile, they can avoid hypoxic conditions that stress sedentary organisms such as Rangia clams. Clams stressed by the combination of severe hypoxia and salinity may be a more profitable prey source for the blue crab. Blue crabs may be able to move in and out of the area of episodic hypoxia to feed on stressed Rangia clams. Differential predation may help explain the lack of mature Rangia clams within the hypoxic zone. The expansion and contraction of the hypoxic zone may produce a blue crab feeding halo around the zone.

To determine if clams exposed to environmental hypoxia enhanced blue crab predation, clams were subjected to severe environmental hypoxia (< 0.75 mg/l) for 72-hours and then exposed to a hungry crab. One hypoxia-stressed clam and one clam kept in normoxic conditions were presented to a blue crab to determine if crabs chose stressed over non-stressed clams. The experiment was repeated sixteen times, with five replicates per experiment. Overall, thirty-two individual crabs were used in this experiment. Although feeding choice varied among crabs, hypoxia-stressed clams were almost always chosen over normoxic clams. Out of 45 total clams, 31 hypoxia-stressed clams were eaten first compared to 12 clams kept in normoxic conditions. Using a binomial sign test with 0.5 probabilities, p=0.0080. The mechanism by which the crabs distinguish hypoxic from normoxic clams is unknown, but likely includes the crabs’ ability to exploit Rangia clam behavioral or physiological responses to hypoxia.

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A Study on Organic Dormancy and Germination of Estuarine Ruppia maritima seeds for Laboratory Propagation and Habitat Restoration Jones, J., and H.J. Cho Department of Biology, Jackson State University, 1400 Lynch St., Jackson, Mississippi 39217

Submerged Aquatic Vegetation (SAV) comprises vascular plants that complete their life cycle underwater. SAV provides shelters, nursery habitats, and food sources to aquatic organisms. It also helps reduce turbidity, improve water quality, and stabilize sediment. Coastal SAV is declining globally due to natural and anthropogenic disturbances; and the needs for restoring SAV and its habitat have increased.

Habitat restoration has several different definitions. National Oceanic and Atmospheric Administration defines it as “The process of reestablishing a self-sustaining habitat that closely resembles a natural condition in terms of structure and function”. Habitat restoration often involves removing exotic species, and/or introducing native species. Seagrass/SAV beds can be restored by (1) encouraging natural recolonization (i.e. through water quality improvement); and/or (2) proactive methods. Proactive methods include transplanting of individuals taken from healthy donor beds or seedlings reared under laboratory conditions. Use of seeds and seedlings grown in laboratory provides cost- and labor-effective alternative means to whole-plant transplanting and has fewer negative impacts on the natural beds than other transplanting methods.

Seed broadcast and seedling propagation have been used in Zostera restoration projects elsewhere. Knowing presence, types, and timings of seed dormancy is suggested as one of the primary requirements for successful seedling propagation. Ruppia maritima L. is a euryhaline SAV that is highly dependent on sexual reproduction, producing numerous seeds (Figure 1) that are protected by sturdy seed coats. R. maritima is the most abundant SAV species in marshes, bayous, and estuaries of Gulf of Mexico; and it is a pioneer species that can colonize and grow rapidly in bare habitat. Therefore, it is a good candidate species to initially re-vegetate areas with recent vegetation losses.

We conducted a laboratory study to understand presence and types of organic dormancy (seed dormancy caused by seed characteristics, not by environmental factors) of the seeds of estuarine R. maritima to develop methods for long-term seed storage that can be employed for SAV propagation in coastal brackish habitat restoration projects. The following hypotheses were tested: (1) Newly matured R. maritima seeds are not in morphological dormancy; (2) R. maritima seeds are in a physical dormant state at time of maturation; (3) Desiccation does not reduce seed viability of R. maritima; and (4) Germination rates of dry-stored seeds do not differ among levels of salinity that naturally occur in local habitat. If mature seeds are in a physical dormancy, desiccation makes it easy to break the dormancy, and desiccation does not reduce seed viability, the seeds, if simply air dried, can be stored for an extended period and used later in SAV restoration projects. Our study results indicate that the brackish estuarine Ruppia maritima population produces

seeds that do not have any noticeable initial morphological, physical, and physiological dormancy. Although dry stratification reduced seed viability (30%) and final germination rates (20-30%), drying seems to induce an earlier germination in R. maritima. Desiccation also appears to induce an environmental dormancy that can be disrupted by exposure to water. Understanding requirements of an organically dormant period immediately after production, along with an understanding of environmental factors that disrupt or induce dormancy is the basic scientific information needed to develop inexpensive propagation methods for SAV restoration. Further study on environmental dormancy is needed to provide information to develop methods for greenhouse seedling propagation.

Figure 1. Relative size of seeds of R. maritima to a penny

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The Prospect for Biological Control of Nutria by Alligators Keddy, Paul 1, J. Andy Nyman2, and Jack Siegrist1 1Department of Biological Sciences, Southeastern Louisiana University, Hammond Louisiana, USA 70454 2School of Renewable Natural Resources, Louisiana State University and Louisiana State University Agricultural Center, Baton Rouge, LA USA 70803. (Video presentation during the Poster session) For more than a decade, wetland scientists in Louisiana have documented the damage caused to wetlands by the introduced herbivore, nutria (Myocastor coypus). Experiments at Turtle Cove show that nutria reduce plant biomass by approximately one-third, which may not only reduce survival of plants, but reduce the accretion of peat that slowly raises the elevation of wetlands. For several decades, a different group of scientists have documented the diets of alligators (Alligator mississippiensis). They have shown that while small alligators eat mainly crustaceans and fish, larger alligators feed heavily upon nutria. A study of the stomach contents from 100 large (1.5-3.0 or 4.5-9 ft) alligators from southeastern Louisiana in 1987, concluded that “Mammals become important to alligators of about 1.5 m in length, and there is a general shift from muskrats to nutria as alligator length increases.” Oddly, there seems to have been reluctance to draw an obvious conclusion from the two types of studies combined – that large alligators might provide a natural biological control upon nutria, and large alligators might provide an important (and free) benefit to wetlands. To explore this possibility further, we reviewed the existing stomach content data, and confirm that nutria form a large part of the diet of large alligators. To explore the possible effects of alligators upon nutria populations, we took an existing model for population growth of nutria, and added in feeding by alligators over a range of body sizes, seasons and population densities. The model showed that alligators might indeed reduce nutria population sizes. The surprise from the model was the broad range of conditions under which alligators appeared to be capable of eliminating nutria. There is therefore evidence that alligators can provide a free ecological service to the state of Louisiana by protecting wetlands from predation by nutria. This is consistent with results from other ecosystems where predators protect plants from herbivores. The value of this free service likely exceeds 4 million dollars a year, the amount currently paid to trappers to carry out the same task. Hunting and trapping may not only reduce alligator density, but more importantly, preferentially remove the largest alligators – the very size class that has the greatest feeding rate upon nutria. Future cost-benefit analyses for alligator management need to consider not only the economic gain from hides, meat and eggs, but also the possible economic losses from increased nutria populations and damage to coastal wetlands. Future research is needed to better quantify the alligator-nutria relationships over a range of habitat and scales. There is a particular need for studies that include plants, grazers and alligators. Owing to the size of the experiments that would be needed, this will likely require collaboration among a large group of managers and scientists.

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The Pearl River Basin: assessing current river condition from bank to bottom, and bottom to top Kennedy, T.B. The Nature Conservancy- Northshore Field Office, Abita Springs, LA.

Since 2003, The Nature Conservancy has focused conservation attention on the Pearl River Basin because it represents one of the most intact river systems in the southeastern United States. The 790-km (490-mi) long, 22,688-km2 (8,760-mi2) watershed represents the full spectrum of floodplain habitats (riverine, palustrine, estuarine, and terrestrial), and provides critical habitat for the endemic Ringed Map Turtle (Graptemys oculifera). The Pearl River Basin also hosts one of the most species rich communities of fishes and mussels in North America (140 fish and 40 mussel species), with three federally listed aquatic species and two federally listed terrestrial species calling the Pearl River Basin home. The catchment contains large blocks of bottomland hardwood forest which is important for many area-sensitive songbirds, and the hardwood forests and adjacent slope forests have been identified as important stopover habitat for migrant songbirds enroute to their nesting and wintering areas. Additionally, the river and its associated high-quality habitats provide a variety of recreational opportunities such as camping, boating, fishing, bird watching, and hunting for the general public.

Recent notoriety of the Pearl has been less than positive. This year, the Pearl was ranked as one of the ten most endangered rivers in the United States by American Rivers, which estimated that approximately 363-km2 (140-mi2) of wetlands and bottomland hardwood forests are at risk from proposals to dam, dredge, and levee portions of the river. These floodplain development projects could further jeopardize a myriad of important linkages that connect a river to its human element, such as impairing environmental services like drinking water, weakening economic prosperity from freshwater and estuarine fisheries, impoverishing social aesthetics, and depreciating recreational enjoyment.

In order to generate a better understanding of the current conditions of the basin, The Nature Conservancy has been conducting field investigations to recognize areas of the river where bank instability and excess sediment input may be particularly acute. Armed with this knowledge, it may be possible to recommend to managers where spatial locations along the drainage are vulnerable to further degradation so that appropriate corrective actions can be focused on the most critical reaches. The Nature Conservancy has conducted geomorphic surveys from just below Ross Barnett Reservoir to the river’s mouth at Lake Borgne. The Nature Conservancy used riparian vegetation and bank condition parameters to visually assess and qualitatively describe bank stability. Sediment samples have also been collected at seven locations to determine the effects of main tributary confluences and to establish a longitudinal profile from upstream of the Strong River in Mississippi to just downstream of the West Pearl River Navigation Canal in Louisiana. These preliminary results will be discussed and linked to land use practices along the river corridor.

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Hyperspectral Analysis for Improved Image Classification of Shallow Estuarine Submerged Aquatic Vegetation Kirui, P. and H.J. Cho Environmental Science Ph.D. Program, Jackson State University, 1400 Lynch St., Jackson, Mississippi 39217

Remote sensing has become an extensively used tool in studies of terrestrial and floating aquatic plants due to the green plants’ distinctive light-reflecting/absorbing properties. On the other hand, remote detection of submerged aquatic vegetation (SAV) has proven to be challenging because of the water absorption properties in the Near Infrared (NIR) regions of the spectrum, and light scattering by suspended particles. SAV beds play critical roles in aquatic ecosystems by absorbing excessive nutrients, enhancing sedimentation, buffering wave energy, serving as food source for wildlife, and serving as critical habitat to aquatic life. Monitoring these beds using field-based sampling is a time-consuming and expensive process; and aerial photography is dependent on the high water clarity and shallow depth of the water to provide valuable information.

We used an experimental approach to: better understand the effects of water depth on SAV reflectance; identify unique spectral regions of the SAV; classify hyperspectral aerial data obtained over locations known to contain SAV. Our research goal is to improve the remote detection of submerged vegetation in relatively turbid and shallow waters. A 100-gallon-outdoor tank was lined with black liner, Myriophyllum aquaticum and Cabomba caroliniana shoots were mounted on the bottom, and filled with water up to 0.5 m. We used a GER 1500 spectroradiometer to collect spectral data over the tank at every 1 cm depth change while water was constantly siphoned out.

Reflectance curves for SAV at varying water depths and at different turbidity were generated through controlled the experiments and the spectral wavelength regions (bands) with distinct spectral peaks and dips were visually selected. The covariance among the depth-induced reflectance variations at those bands was studied in order to find the three key wave bands to reduce redundancy of the data.

Airborne data were obtained in October 2003 over seagrass beds in Middle Bay of Grand Bay National Estuarine Research Reserve, Mississippi. The data were obtained by the AISA Eagle hyperspectral sensor and pre-processed for atmospheric and geographic corrections by University of Nebraska at Lincoln. The data contained 20 hyperspectral bands ranging from 435 to 950 nm. Spectral Angle Mapping (SAM), a supervised classification technique based on the idea that observed reflectance spectrum is a vector in a multidimensional space where the numbers of dimensions equal the number of spectral bands, was utilized to classify the AISA data. Only the three AISA bands whose centers were closest to the three key wavelength regions (561nm, 710nm, and 819 nm) were used in SAM classification. Regions of Interests (ROIs) were selected as polygons to represent un-vegetated deep water, shallow-water with SAV, marsh, and bare sand. The three AISA bands were used to create an ENVI file with ENVI 4.1 program, which was then used for classification.

The SAM-classified image was imported into ArcGIS 9.2 and re-projected into Universal Transverse Mercator (UTM) zone 16 (datum WGS 84) to be overlaid with our field SAV survey data. Compared to the original 20-band image, use of the NIR bands made chlorophyll-containing objects, both SAV beds and waters with high phytoplankton concentrations, more distinguishable. While the shallow areas near the shore were correctly classified as SAV, the overall accuracy for the SAV class was less "than 30%" when compared to the field transect SAV distribution data probably due to the high-suspended particles, which reduced signals from the substrates. Phytoplankton with similar spectral signals to those of vascular plants may also have introduced sources for the misclassifications.

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Characteristics of the 2008 Bonnet Carré Spillway Plume in Lake Pontchartrain: Measures of physics, water quality, and plankton communities. C.Y. Li, J.R. White S. Bargu, N. Walker, W. Fulweiler, and R.R. Twilley Department of Oceanography and Coastal Science, Louisiana State University

The Bonnet Carré Spillway was opened to relieve the high flood stage of the Mississippi River. At the height of the opening, flow was greater than 100,000 cfs into Lake Pontchartrain. Nitrate, soluble reactive P, ammonium, DO, chlorophyll, total suspended solids were measured 6 times along a 10 station transect initiating at the I-10 bridge and traversing the lake toward the NE to the causeway over a distance of 29.5 km. Sampling began during the full opening of the spillway and continued for several months after closure. Satellite imagery was utilized to determine the relative position of the plume with respect to the transect at each sampling time. In addition, a separate boat covered the southwestern lake near the Spillway several times including one day before the opening of the Spillway and 5 times during the flood period. During these surveys, hydrographic data, water samples, and / or water flow velocity profiles were collected / measured.

The plume was significantly colder and fresher but was not low in dissolved oxygen either at the surface or at mid-depth. The colder plume temperatures were clearly distinguishable using satellite imagery. The nitrate levels mimicked the Mississippi river at 1.25 mg NO3-N L-1 and were 4 times higher than the lake water outside the plume. The soluble reactive P was also higher at 0.053 mg P L-1 which was 8 times higher than lake water outside the plume. There was no vertical stratification of nutrient concentrations during the event. During the spillway opening, satellite imagery and field measurements suggested there was little mixing of the plume with the ambient lake water. The effect of the spillway opening dissipated shortly after closing with nitrate levels dropping below 0.5 mg NO3-N L-1 at most stations in less than 3 weeks. Although the spillway was closed, the stations in closest proximity still registered high nitrate levels as there was some leakage of river water through the structure due to high stage. During the opening and right after the closing, diatoms were the dominant plankton group. Chla started to increase after the closing, reaching the highest concentration three weeks after the spillway closing. Diatoms were eventually replaced with toxic cyanobacteria including Anabaena, Microcystis and Cylindrospermopsis with peak toxin concentration approximately 0.1 µg microcyctin L-1. Hydrodynamic data using acoustic Doppler current profilers were also collected at the three tidal channels of the lake in estimating the net transport of water in and out of the lake, and the flushing time and pathway of the Mississippi River water diverted into the lake.

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Application of the Multiple Lines of Defense Strategy to Planning Units 1 and 2, in southeast Louisiana Lopez, J. A.1, N. Snider2, P. Kemp3, and C. Dufrecou1, 1 Lake Pontchartrain Basin Foundation , 2 Coalition to Restore Coastal Louisiana, 3 National Audubon Society Introduction South Louisiana appears to have entered a period when (1) coastal land loss and (2) more frequent intense hurricanes are threatening its viability. The Multiple Lines of Defense Strategy (MLODS) is proposed to address this enhanced threat of storm surge to coastal communities (Lopez, 2006). This strategy includes two fundamental elements:

1) Utilizing natural and manmade features that directly impede storm surge or reduce storm damage (Lines of Defense),

2) Establishing target goals for wetland habitat distribution to be sustained using diversions and other tools (Wetland Habitat Goals).

The MLODS has been adopted by the State of Louisiana in the Integrated Ecosystem Restoration and Hurricane Protection: Louisiana’s Comprehensive Master Plan for a Sustainable Coast (CPRA, 2007). It has also been adopted by the United States Army Corps of Engineers (USACE) to guide the Louisiana Coastal Protection and Restoration Plan (LACPR) project. The current MLODS report (Comprehensive Recommendations Supporting the Use of the Multiple Lines of Defense Strategy to Sustain Coastal Louisiana 2008 Report (Version I) LPBF and CRCL, 2008) covers all of coastal Louisiana, but we focus here on southeast Louisiana. Planning Units 1 and 2

Planning Units 1 and 2 are located east and west of the Mississippi River, and therefore, can more readily use freshwater, sediments and nutrients available in the river than other planning units. Both planning units serve as the coastal surge buffers for New Orleans and other outlying communities and are discussed together in this summary.

The natural lines of defense critical in Planning Units 1 and 2 are shown in yellow, while area protected by levees are depicted in red (Figure 1). Levees generally follow natural ridges and provide protection against both hurricane surge and high water caused by river diversions. For Planning Unit 1, the natural landscape features identified as critical lines of defense are the Chandeleur Islands, Biloxi Marsh Land Bridges, East Orleans Land Bridge, Maurepas Land Bridge, Lake Pontchartrain South Shore marsh buffer, and Bayou La Loutre Ridge (Figure 1). West of the Mississippi River, the natural landscape features identified as critical Lines of Defense are the Barataria barrier islands, Westwego to Lockport Land Bridge, Barataria Basin Land Bridge, Lower Plaquemines marsh buffer, Golden Meadow to Mytrle Grove Land Bridge, and Bayou Grand Chenier Ridge.

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Figure 1: Natural Lines of Defense shown in yellow and proposed levee-protected areas in red.

Figure 2: ADCIRC maximum elevation of water prediction for Hurricane Gustav (September 1, 2008) by LSU and University of North Carolina (2008)

Surge model output for Hurricane Gustav (Figure 2) is similar to that of other storms in showing higher

surge elevations associated with the lines of defense identified above. One exception is that for Gustav, little inland effect was predicted for the Chandeleur Islands. The Chandeleur Islands affect surge and waves more for slower moving, more powerful storms like Katrina.

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Figure 3: Recommended Lines of Defense for Planning Units 1 and 2. Green outlines are marsh land bridges where marsh creation is recommended. White arrows are proposed sustaining diversions. Red arrows are proposed controlled crevasses.

Restoration recommendations are designed to restore and sustain the critical lines of defense in Planning

Units 1 and 2 (Figure 3). Marsh creation targets for land bridges areas were established to re-capture the landscape integrity of that specific feature that could be sustained by a local fresh water diversion. Both “sustaining diversions”, which are designed for a minimum annual discharge, or “controlled crevasses”, capable of conveying higher discharges during high water on the Mississippi river are recommended. The total marsh creation proposed for planning Unit 1 is 20,000 acres, and for planning Unit 2 it is 29,000 acres. Thirteen sustaining diversions and two controlled crevasses are proposed for planning unit 1 with combined annual sustaining discharge of 190,400 cubic feet per second (cfs) and a combined high water discharge of 600,000 cfs. For Planning Unit 2, ten sustaining diversions and two controlled crevasses are proposed with combined sustaining discharge of 215,650 cfs and a combined high water discharge of 482,650 cfs.

In Planning Unit 2, a land-building diversion is proposed at Buras out of the west bank of the River upstream of Head-of-Passes (Figure 3). This area has already lost virtually all of the wetlands, which were present a century ago, depriving lower Plaquemines Parish of its coastal wetland buffer entirely. Six miles of open water extend from the parish levee to a broken gulf shoreline, where the remaining barrier islets are less than 900 feet wide. Short term marsh creation is recommended near the levee and to repair the gulf shoreline. However, due to the catastrophic loss, high subsidence, and the great need for a sustainable coastal buffer along this corridor, a land building diversion is considered the only long term option to sustain lower Plaquemines Parish. A discharge of 140,000 cfs is recommended, which is comparable to that of the Wax Lake Outlet during normal Atchafalaya River discharges. It is estimated this will build 1 to 2 square miles of wetlands per year that will eventually reoccupy the open water area now separating lower Plaquemines from the Gulf of Mexico.

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Some of the recommendations for Planning Units 1 and 2 are based on assumptions that will benefit from further testing, so additional technical analysis is proceeding. Hydrodynamic models of Planning Units 1 and 2 are being developed to evaluate the sustaining and restorative effect of operating multiple diversions simultaneously, or sequentially within basin, or rotating discharge among them. Modeling will be initiated for the Mississippi River itself in 2009 to assess the response within the River to discharge of the proposed diversions in both planning units.

References Cited CPRA, 2007, Integrated Ecosystem Restoration and Hurricane Protection: Louisiana’s Comprehensive Master Plan for a Sustainable Coast. Draft report by the Coastal Protection and Restoration Authority, Final report April 2007 Lake Pontchartrain Basin Foundation and the Coalition to Restore Coastal Louisiana, 2007, Comprehensive Recommendation supporting the Use of the Multiple lines of Defense Strategy to Sustain Coastal Louisiana www.MLODS.org Lopez, J. A., 2006, The Multiple Lines of Defense Strategy to Sustain Coastal Louisiana, Lake Pontchartrain Basin Foundation, Metairie, LA. http://www.saveourlake.org U.S. Army Corps of Engineers, 2004, Louisiana Coastal Area –Ecosystem Restoration Study, Final Report- November 2004, The Appendices

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The Bohemia Spillway in southeast Louisiana: What Little we know and what we should know Lopez, J.A.1, P. McCartney2, M. Kulp2 and P. Kemp3 1Lake Pontchartrain Basin Foundation, 2Pontchartrain Institute for Environmental Sciences, and 3National Audubon Society

The Bohemia Spillway area is defined here as the 12 mile reach on the east bank of the Mississippi River approximately 45 miles downriver of New Orleans extending below the terminus of the Mississippi River (MR&T) levees to Bayou Lamoque (Figure 1). The Bohemia Spillway area has a complex legal and historical legacy since approximately 33,000 acres were authorized to be expropriated in 1924 by the Louisiana state legislature (United States Court of Appeals, the Fifth Circuit, 2002). Although the legislature moved to return the property in 1984, it was not until 2006 that heirs to the prior landowners won back their property through more than a decade of litigation.

Figure 1: Bohemia Spillway area is east of the Mississippi River downstream of the terminus of the Mississippi River levee (source basemap: SONRIS CIR 2005).

From approximately 1924 to 1984, the Bohemia Spillway was under management by state agencies,

such as various levee boards and predecessor agencies to the Department of Wildlife and Fisheries and the Department of Natural Resources. Landscape management goals are unknown, but may have been for fisheries management or management of river flood stage. USGS quad maps and the Louisiana Coastal Zone Map (2002) identify the area as the Bohemia State Wildlife Management Area or Point a la Hache Relief Outlet. Little is known and or well documented about the Bohemia Spillway region, but it may prove be an analogue for riverine processes and instructive to coastal restoration.

Informal investigation of the Bohemia Spillway area by the Lake Pontchartrain Basin Foundation, National Audubon Society and Pontchartrain Institute for Environmental Sciences began in 2007 and 2008, and is ongoing. Below are some preliminary observations. • A natural levee is present throughout the Bohemia spillway region and is the dominant landform. It has

been impaired, including at least; historical deforestation, dredging of canals, an elevated road made of limestone rubble, several borrow pits, river channel bank stabilization, and land clearing for roads, pipelines and power lines.

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• The forested natural levee crest near the river is probably four to six feet above sea level and slopes eastward toward the marsh and Breton sound. On average, the width from the river to the sound is three miles.

• The forest has indigenous species, such as live oak, black willow, and baldcypress, but also invasive species such as tallow. The marsh transitions over a few miles from intermediate to brackish. In places within the marsh, dense stands of Roseau cane are present. Most of the trees appear relatively immature except for some live oak located on a spoil bank adjacent to the natural ridge. Marsh habitat appears healthy with relatively firm soils (non-quantified observations).

• At least three generations of engineered river discharge structures are present and include an uncontrolled spillway weir with a concrete embankment, a controlled diversion with three box culverts, and several uncontrolled pipe culverts. All of these structures have a history of function and subsequent damage. Most are now abandoned and may be non-functional. Locals report that annually the road (and natural levee) can have minor overtopping by river discharge for short durations. Although outside of the Bohemia spillway, two additional historical diversions are located nearby at Bayou Lamoque and may have influenced the Bohemia Spillway area habitats when they were operational. A new generation of diversion within the Bohemia Spillway area has been authorized by CWPPRA.

• Land loss maps or land change maps by the USACE and by the USGS illustrate that, except for the direct wetland loss from canal excavation and slight shoreline erosion near the sound, land loss of the wetlands within the Bohemia Spillway region are low, being approximately 20% loss from 1932 to 1990 (Figure 2). “Interior” patterns of marsh loss commonly seen elsewhere in the Louisiana coast are not present.

Figure 2: Composite wetland loss (change) map from USGS and USACE data sources (LPBF and CRCL, 2008).

In 2008, the Mississippi River was at flood stage from March 13 to July 20 and during this time several visits to the Bohemia Spillway area and an over flight reconnaissance were conducted. Some landscape (elevation) and hydrologic (velocity) data were collected. During the 2008 flood event, 1.7 miles of the riverbank were

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observed to have four active flowing breaches with incision through the road and into the natural levee (Figure 3). In addition, the natural levee and road were overtopped for 0.6 miles with a depth of 0.1 to 1.5 feet (Figure 4). Although overtopping observed in 2008 was influenced by the road and other human alterations, the 2008 event and future flood events at Bohemia Spillway may represent the best modern analogue to the natural riverine process of overbank discharge on the lower Mississippi River. In addition, the history of success and failure of successive diversion structures within the Bohemia Spillway may provide valuable lessons for designing future structures. The curiously low historical land loss is anomalous and begs the question: ‘why?’

Figure 3: Mississippi River discharge through a breach eroded through the road and into the natural levee within the Bohemia Spillway area during high water on May 24, 2008.

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Figure 4: Mississippi River flow overtopping the road on the natural levee within the Bohemia Spillway area during high water on May 5, 2008

References Cited Lake Pontchartrain Basin Foundation and the Coalition to Restore Coastal Louisiana, 2008, Comprehensive Recommendation supporting the Use of the Multiple lines of Defense Strategy to Sustain Coastal Louisiana www.MLODS.org United States Court of Appeals, the Fifth Circuit, 2002 no. 01-30728, Anthony L. Vogt, versus Board of Commissioners of the Orleans Levee District, and James Huey.

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Blue Crab Migratory Routes into Lake Pontchartrain Lyncker, L.A. HDR Engineering Inc., Metairie, LA

The blue crab, Callinectes sapidus, is a commercially and ecologically important species for Louisiana.

This estuarine dependant species requires the entire salinity gradient to complete its complex life cycle of planktonic, nektonic, and benthic existence. C. sapidus utilizes tidal and current movement within an estuarine system such as Lake Pontchartrain as means of transportation out of, back into, and also within the estuary. Louisiana provides an optimal estuarine environment due to its large amount of open marsh, though regions along the state’s coastline are experiencing accelerated effects of land loss and major impacts from urbanization. As habitats are threatened, those environmental elements that construct essential habitats need to be determined and preserved. A better understanding of the species’ use of Lake Pontchartrain and their selective use of currents throughout the estuary is imperative for future management efforts and habitat utilization mapping.

Callinectes sapidus densities were quantified at six sites around Lake Pontchartrain from March 2006 to February 2007 using a 1 m3 throw trap. MODerate-resolution Imaging Spectroradiometer (MODIS) 250 m data were analyzed to assess and monitor the mass water movement, which likely influenced where early life stage C. sapidus recruited and settled within Lake Pontchartrain. Throw trap data indicated there were two considerable recruitment and settlement events, the larger in May and June and the smaller in September and October. The data also support that early life stages C. sapidus were transported through differing migratory routes during the two recruitment events. The earlier larger recruitment event occurred through the Inner Harbor Navigational Canal (IHNC), where as the second recruitment event occurred through the more eastern situated, natural inlets into Lake Pontchartrain, the Rigolets and Chef Menteur passes. Differing wind and tidal patterns within each recruitment event induced transport of early life stage C. sapidus into Lake Pontchartrain via two different migration pathways. While environmental conditions of the late summer and early fall C. sapidus recruitment have been illustrated in various reports in the northern Gulf of Mexico, conditions underlying the first recruitment noted in this study via the IHNC have not been thoroughly explored and require further investigation.

Early life stage C. sapidus were transported via two different pathways and were introduced into two different regions of Lake Pontchartrain; however, the majority of C. sapidus were collected in the eastern region of Lake Pontchartrain. Environmental and remote sensing data demonstrate the great amount of wind and tidal induced currents within Lake Pontchartrain, and those data along with throw trap data support that C. sapidus were transported throughout the entire system. Habitat accessibility did not appear to limit C. sapidus distribution within Lake Pontchartrain. The lack of suitable nursery habitat in the further westward regions of Lake Pontchartrain could have limited the distribution of early life stage C. sapidus to the northeast and eastern region of Lake Pontchartrain.

Ultimately, this approach of applying remote sensing techniques to ecological investigation appears to be a very useful tool in monitoring important large-scale estuarine processes, which impact large-scale ecological processes. As established by this study, MODIS 250 m data can be used to monitor large-scale influential water movement patterns utilized as means of transportation during C. sapidus recruitment events. This study, which combined field and remote sensing investigation highlighted the IHNC and potentially the Gulf Intracoastal Water Way (GIWW) and Mississippi River Gulf Outlet (MRGO) as important corridors of migration between upper and lower estuarine habitats. Remote sensing techniques were and can be used to more completely understand C. sapidus and possibly other estuarine species recruitment dynamics and variations in distribution and abundance patterns within Lake Pontchartrain.

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Historical Shoreline Changes and Barrier Island Land Loss along Louisiana's Gulf Shoreline: 1800's – 2005 Martinez, Luis A.

1, S. Penland

1, 2, S. O’Brien

1, M. Bethel

1, F. Cretini

1, P. Guarisco

1, I. Lacour

1, D. Lee

3

1. Pontchartrain Institute for Environmental Sciences, University of New Orleans, 2045 Lakeshore Drive, CERM Bldg. 362, New Orleans, LA 70148

2. Department of Earth and Environmental Sciences, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148

3. Louisiana Department of Natural Resources, Office of Coastal Restoration and Management, Thibodaux Field Office 1440 Tiger Drive, Suite B Thibodaux, LA 70301

The Louisiana Coastal Zone is losing land at rates of up to 100 km

2/yr, resulting in drastic changes to

shoreline position, geometry, and configuration. In order to: 1) establish a baseline dataset for future restoration efforts, 2) define the character and patterns of historical shoreline change, and 3) quantify the rates of linear shoreline retreat, a comprehensive shoreline change analysis of the entire Louisiana Gulf shoreline was undertaken. To document historical rate and range of Louisiana Gulf shoreline change for the period from 1855 to 2005 and provide a comprehensive quantification of shoreline evolution trends along Louisiana’s Gulf shoreline, historical maps, satellite imagery, and aerial photography, patterns and rates of shoreline change were used for 4 time periods: 1855-2005 (historical term), 1920’s-2005 (long term), 1996-2005 (short term), and 2004-2005 (near term). The high-water line was used as the official shoreline and was interpreted and determined on the aerial photography and satellite imagery according to the location of the wet and dry-beach contact or the high-water debris line. Measurements of shoreline movement and change were taken along transects perpendicular to an offshore baseline spaced at 50 meter intervals alongshore. The shoreline was divided into 80 reaches based on the geomorphology, coastal evolution trends, existence of man-made structures, and/or a combination of these factors.

The average historical rate of shoreline change is -2.7 m/yr. The average long-term rate of shoreline change is -4.2 m/yr. During the last decade, shoreline change rates have increased to -8.2 m/yr. The impacts of Hurricanes Katrina and Rita in 2005 accelerated the near-term rate of erosion to -57.8 m/yr. The highest rates of erosion due to the 2005 storm impacts were found along the Mississippi River delta barrier islands of Isle Derniers, Timbaliers, and Chandeleur Islands with some sectors undergoing over 182 meters of landward retreat. Beach nourishment, dune construction, and backbarrier marsh creation projects were the only areas where shoreline retreat was not detected in this study.

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Development of coastal wetlands education in the Lake Pontchartrain Basin: A ten-year retrospective Maygarden, D.F., Egger H. L., University of New Orleans, New Orleans LA

In response to LPBF’s Comprehensive Management Plan of 1995 and its call for public education about Lake Pontchartrain Basin environmental issues, in 1997 the Coastal Research Lab of the Department of Geology at the University of New Orleans began a partnership with the LPBF to develop an education program focusing on bringing school students to nearby wetlands to learn about wetland issues. This program allowed students to experience canoe and land-based trips in the wetlands near their homes while learning about the habitats and the issues that impact them. All the trips involved investigative science learning activities. About thirty trips per school year were completed and 800-1000 students, teachers and chaperones per year benefited from the program. This popular wetlands education program has evolved over the past decade so that in 2002 it became one of the programs of the Pontchartrain Institute for Environmental Sciences (UNO-PIES). With funding from the NOAA Pontchartrain Restoration Program (NOAA-PRP), the program has grown to provide many opportunities for people of all ages to learn about the issues affecting our coastal wetlands in Louisiana. The NOAA-PRP funds continue to be critical to this program, although we also strive to find additional sources of funding.

In a recent typical year the staff of the program conducts 20-30 field trips for students; two to three teacher professional development workshops with field trips; ten to twenty activities in partnership with other educational groups such as the Wetland Watchers, the Lake Pontchartrain Basin Maritime Museum (LPBMM) in Madisonville, and the US Fish and Wildlife Service Southeastern Louisiana Refuges; as well as approximately ten public events such as festivals and fairs. Examples include Earth Fest at Audubon Zoo and Baton Rouge Earth Day. In addition, the staff is active on the state level in environmental and wetlands education professional development. Each year we produce educational products related to the coastal wetlands. These have included posters focusing on the Lake Pontchartrain estuary, videos on coastal restoration projects in the Pontchartrain estuary and a guidebook to the wetlands of the Lake Pontchartrain Basin. We work to bring the many geospatial products of the UNO-PIES GIS lab to the public and teachers in a way that provides comprehensive interpretation. These products are extremely valuable for explaining the complexities of our rapidly changing coastline. We have also partnered with groups such as Barataria-Terrebonne National Estuary Program (BTNEP) to produce a series of posters focusing on the barrier islands of that area and an ID guide of invasive species.

In 2007 and 2008 our focus began to shift to the development of a wetlands education program located at a facility in the wetlands of eastern New Orleans. The Pontchartrain Institute and College of Sciences at UNO is developing this facility, located at Highway 90 and Chef Pass, as a Coastal Education and Research Facility. A coastal education and research facility opens a wide range of possibilities and opportunities for residents of the greater New Orleans area to learn about the coastal wetlands that serve to protect their homes and livelihoods. There are three main strands of opportunity that will develop with the facility:

First, it will enhance the ability of UNO to offer quality field-based environmental science education at all levels, including to K-12 students, teachers, undergraduate and graduate students, and adults seeking increased knowledge base;

Second, it will greatly enhance the ability of UNO research scientists to carry out the vital task of data acquisition and analysis in order to understand our coastal dynamics and inform the coastal restoration, enhancement and protection process;

Third, by providing opportunities for college students to participate in field research, UNO will help train a workforce necessary to carry out the essential tasks of coastal management, restoration and protection in coastal Louisiana. The facility is located on the Eastern New Orleans Land Bridge, between Lake St. Catherine and Lake Pontchartrain and is identified by coastal managers as a critical line of defense for Lake Pontchartrain and greater New Orleans from storm surges. The wetlands of this area are mostly brackish marsh, with the exception of areas of wooded higher ground on the ridge that Highway 90 follows. There are

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excellent opportunities for access to these wetland areas for educational field trips and research. We are now waiting for the renovation to be complete so that we can begin operating at the CERF. Full operation is scheduled for early spring 2009. We plan to offer field trips to the facility for schools; teacher professional development workshops and coastal restoration focus workshops for community members.

We are currently developing partnerships with several key players in the coastal education community

in order both to strengthen our program and offer support to other programs. These partners include LSU’s Coastal Roots Program (LSU-CR), which has a subcontract in our current NOAA-PRP contract, and USFWS’s Bayou Sauvage and Big Branch education programs. We anticipate that these partnerships will continue as we bring our programming to the CERF. LSU-CR will have access to the facility for growing seedlings, potential planting projects and other activities. The close proximity of Bayou Sauvage National Wildlife Refuge to the CERF provides many possibilities for continued partnership with the USFWS. We continue to seek partnerships with colleagues in federal and state government agencies, regional universities and colleges, and non-governmental organization.

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Water Quality Modeling of 2008 Bonnet Carré Diversion into Lake Pontchartrain Rachel Roblin1, Alex McCorquodale1 and Ioannis Georgiou1, FMI Environmental Modeling Center/PIES, University of New Orleans, New Orleans, LA

A 1-D (link-cell) tidal, salinity and water quality model has been developed to simulate the general effects of freshwater diversions have on water quality in the Pontchartrain Estuary. A 17-year long record of water quantity and water quality was assembled for the calibration and validation of the link-cell based hydrodynamic and water quality model. The data sources included were: NOAA, USGS, USACE, US EPA, LADNR, LADEQ, UNO, LSU, ULL and LPBF. The parameters included: discharge, stage, water and air temperatures, suspended sediment/turbidity, nitrogen and total phosphorus. The 17-year record was split into 5-year calibration and 12-year validation datasets. The calibrated and validated model was tested in a predictive mode for the 2008 Bonnet Carré Spillway Opening.

Figure 1 shows the structure of the model which consisted of a series of storage elements (cells) connected to one another via channels (links). The model is driven by the evaluation of the differential water levels between cells that are connected by links.

Figure 1: Cell-link model structure for Pontchartrain Estuary model.

The occurrence of algal blooms was determined from two indices. The first index considered at the probability of an algal bloom occurring (Ismail, 1999, Haralampides, 2000 and Dortch,1999, 2001). The probability is shown below:

( ) 41

)(, jDINCCCSCSSTjHAB ppppp =

where pHAB,j = probability of a harmful algal bloom occurring in each cell; pT,j is the index of suitable water temperature and light in each cell; pCSS,j is the index of suitable suspended sediment concentration in each cell;

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pCS,j is the index of acceptable salinity concentration in each cell; and pCC(DIN)j is the index of available dissolved inorganic nitrogen (DIN) concentration in each cell.

The second index was based on the relative concentration of live algae in each cell, where live ‘algae’ is considered a surrogate for chlorophyll a. This parameter is based on the simplified model shown in Figure 2 where the inputs to each cell in the model (from rivers, atmosphere, runoff, etc) are considered but not shown. Live ‘algae’ is treated as an index rather than an absolute concentration since it has not been completely calibrated due to the lack of data.

Figure 2. Diagram showing chemical interactions considered in the Pontchartrain Estuary model. External

loads are not shown.

When the simulated live algae concentrations are used in conjunction with the algal bloom probability model, reasonably good predictions of algal bloom occurrences between 1990 and 2006 were achieved. The model successfully predicted the observed algal blooms in 1993, 1994, 1995, and 1997 and predicted two undocumented blooms in 1991 and 2004.

The 2008 opening of the Bonnet Carré Spillway was simulated by this model. The Bonnet Carré nutrient concentrations and suspended solids were taken from the 1997 dataset. The ambient conditions around the Estuary (temperature, nutrient inputs, etc.) were assumed to be the same as those in 1990. The 2008 spillway hydrograph was based on preliminary information from Dr John Lopez. The Spillway flow including leakage started in late March reaching a peak flow of about 165,000 cfs in the third week of April and then declining to zero flow in Early May. Figure 3 shows the modeled DIN for the 2008 Bonnet Carré opening. The highest DIN were in the SW and SE cells of the Lake.

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Figure 3. Total Dissolved Nitrogen Response in Lake Pontchartrain Figure 4 shows the live ‘algae’ index for the simulated 2008 opening of the Bonnet Carré Spillway for each cell in Lake Pontchartrain. The live algae index lags the peak DIN with the highest index in the NW of Lake Pontchartrain in late April or early May. Figure 5 shows the corresponding probability plot which indicates the potential for ideal conditions for an algal bloom based on DIN, Turbidity, water temperature and salinity. Figure 5 shows that there is intermittent conditions for an algal bloom in the NW and SW in late April and early May; however, the ideal conditions decline during May. The fluctuations in the probability reflect turbidity modulation due to colloidal suspension in the Mississippi River water and due to wind generated resuspension in the Lake. The 2008 algal bloom index of approximately 2 and 30% to 90% probability compares to the corresponding index of 2.8 and 80% to 90% for the 1997 Spillway opening when an extensive bloom occurred. Consequently, the model results indicate that the 2008 algal bloom was weaker than the bloom in 1997 and was likely to be limited to the NW cell.

Figure 4. Simulated Live Algae Index for 2008 based on 2008 Bonnet Carré Flow and the 1990 Tributary Flows.

LiveAlgae Index

11.21.41.61.8

22.22.42.62.8

3

2008 2009Date

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Figure 5. Probability that the Ambient Conditions are Ideal for an Algal Bloom for 2008 based on 2008 Bonnet Carré Flow and the 1990 Tributary Flows.

Acknowledgements This research was funded through grants by the Pontchartrain Restoration Program/National Oceanic and Atmospheric Administration, and CLEAR through funds by the LCA Science and Technology Office.

References Cited 1. Roblin, R.; 2008. Water Quality Model for Lake Pontchartrain. Master’s Thesis. University of New

Orleans, New Orleans, LA. 2. Ismail, I. A. (1999). Lake Pontchartrain water quality and algal bloom assessment. A

Thesis for Master of Science in the Civil and Environmental Engineering Department, University of New Orleans, New Orleans, LA.

3. Haralampides, K. (2000). A study of the hydrodynamics and salinity regimes of the Lake

Pontchartrain system. A Dissertation for Doctor of Philosophy in Engineering and Applied Science in the Department of Civil and Environmental Engineering, University of New Orleans, New Orleans, LA.

4 Dortch, Q., Peterson, T., and Turner, R. E. (1998). “Algal bloom resulting from the opening of the Bonnet Carré Spillway in 1997.” Proceedings of the Basics of the Basin research symposium, U.S. Geological Survey, New Orleans, LA.

Probability of Algae Bloom

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Priority Conservation Areas in the Lake Pontchartrain Estuary Zone McInnis, N. C. (1), B. Rogers (2), (1)The Nature Conservancy, P. O. Box 1497, Covington, LA, 70434; (2)Lake Pontchartrain Basin Foundation, 3838, N. Causeway, Suite 2070, Metairie, LA, 70002.

This poster is a result of a project completed in December 2006 to identify priority conservation areas

within the Lake Pontchartrain Estuary that are thought to significantly contribute to the ecological integrity of the region, and are in addition to existing conservation areas within the estuary. The resulting map is not to suggest that areas not identified are unimportant for conservation. However, it is meant to focus limited conservation resources to work in cooperative ways with landowners of areas that may be most important from an ecological standpoint. The base map data was provided by USGS as part of the LOSCO GIS Data DVD. Boundaries of some of the data presented, such as extent of submersed aquatic vegetation and benthic dead zone, has changed since this project was completed, however, we feel it is still valuable in considering area for potential restoration, and wanted to make this poster available to those interested in the Lake Pontchartrain Basin. The boundary of this project was based primarily on that developed for the Conservation Area Plan for the Lake Pontchartrain Estuary (The Nature Conservancy, 2004). It was chosen to provide sufficient focus on immediate estuarine, palustrine, and aquatic habitats, and is linked to both tidally influenced habitats and habitats affected by less frequent wind driven tidal surges. The northern boundary was extended to Interstate-12 to match that of the LA Coastal Zone. The poster provides boundaries and commentary on the following items:

Existing Conservation Areas Recommendations for Future Conservation including Submersed Aquatic Vegetation (SAVs); Rangia

Clam Habitat; Benthic Dead Zone (pre-Hurricane Katrina); Lines of Defense/Land Bridges; Potentially Sustainable Cypress Forest; Proposed Maurepas Diversion and Amite River Diversion Canal Gapping Projects (Future Sustainable Forest); Large blocks of Bottomland Forest and Other Forested Wetlands.

Additional Areas for Conservation Management: Buffers for existing conservation areas; In-holdings and areas that connect existing conservation areas; Sites for species of concern; Old growth or mature forests; Key habitat types for conservation targets; Natural areas with significant habitat loss; Important hydrologic areas.

This project was completed by The Nature Conservancy and the Lake Pontchartrain Basin Foundation, with contributions from Shell Exploration and Production Company. The poster includes recognition of the many scientists and agencies that provided information toward this project.

The Nature Conservancy. 2004. Conservation Area Plan for the Lake Pontchartrain Estuary. Northshore Field Office. 128pp.

The Nature Conservancy, 2004, Priority Conservation Areas in the Lake Pontchartrain Estuary Zone, map http://www.nature.org/wherewework/northamerica/states/louisiana/files/estuary_zone_final_s.pdf

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The Role of Hurricanes in the Long-Term Evolution of the Chandeleur Islands: Implications for Barrier Management Miner, M.D.1, M.A. Kulp1,2, I. Georgiou1,2, D. FitzGerald3, J. Flocks4, D. Twitchell5, and A. Sallenger4. 1Pontchartrain Institute for Environmental Sciences, University of New Orleans, New Orleans, LA, 70148, 2Department of Earth and Environmental Sciences, University of New Orleans, New Orleans, LA, 70148, 3Department of Earth Sciences, Boston University, Boston, MA, 02215, 4U.S. Geological Survey, Florida Integrated Science Center, St. Petersburg, FL, 33701, 5U.S. Geological Survey, Woods Hole Science Center, Quissett Campus, Woods Hole, MA, 02543

Shoreline and seafloor change analyses based on historic hydrographic and topographic data (dating to 1768) and satellite imagery for the Chandeleur Islands reveal long-term trends of barrier shoreface retreat, and recently, barrier disintegration and in-place drowning. Volume calculations indicate ~150 x 106 m3 of sediment has been deposited downdrift (northward) and seaward of the northern terminal spit during the past 125 years. A similar volume of sediment has accreted at the extreme southern limits of the island chain (south of Breton Island). However, the volume deposited in the backbarrier is only half of that distributed to the flanks, suggesting the dominant transport mode is alongshore as opposed to cross-shore. The depositional sinks at the flanks of the island arc accreted at rates of more than 1 x 106 m3 yr-1 between 1870 and 2007, however, calculations of potential longshore sediment transport rates based on 20 yrs of offshore wave data are two orders of magnitude less than the accretion rates. The sediment sources for these accretionary zones at the flanks include: (1) relict deltaic deposits eroded from the shoreface where ~790 x 106 m3 of erosion has occurred since 1870, (2) nearshore and subaerial barrier sand, and (3) collapsed ebb tidal deltas that sequestered sediment during earlier stages of barrier evolution as indicated by historic charts and stratigraphic data. Recent bathymetric and shoreline analyses as well as wave and current velocity data collected during Hurricanes Gustav and Ike in 2008 suggest that the islands are impacted primarily during major hurricanes, resulting in shoreface retreat in some sectors and shoal development and in-place drowning in others.

Hurricane Katrina segmented the island arc into multiple small marsh islets separated by wide hurricane-cut tidal passes. More than 90% of sand comprising the barriers was removed, exposing backbarrier marshes to wave attack. During the following year, >50% of the length of the northern Chandeleur Islands shoreline continued to erode (>200 m landward retreat, locally). However, during year two of recovery, marsh islands served as nucleation sites for sand accumulation along the northern arc. Early stages of recovery were marked by sand and shell recurved spit formation at hurricane-cut tidal passes. This was followed by onshore bar migration and welding, a process that resulted in the closure of some inlets.

Prior to the 2008 Hurricanes, elevation along the northern section began to increase as eolian processes constructed dune fields in the wind shadow of black mangroves and roseau cane thickets. Contrastingly, southern segments of the chain, where marsh islands were absent, underwent transgressive submergence. These southern shoals persisted for 2 years after Katrina’s impact, but began to emerge as narrow, ephemeral barrier islands until they were once again destroyed by Hurricanes Gustav and Ike. Long-term reduction in island area is driven by pulses of rapid land-loss triggered by storm events. The islands do not fully recover from storm impacts because sand is transported to the flanks of the arc removing it from the littoral system. These downdrift sand reservoirs may provide a unique, quasi-renewable resource for nourishing the updrift barrier system.

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Effect of Bonnet-Carrie Spillway opening on spatio-temporal variability of water quality parameters in the Lake Pontchartrain Mishra, S. , D. R. Mishra Pontchartrain Institute for Environmental Sciences Department of Earth & Environmental Sciences University of New Orleans, New Orleans, LA

Spatio-temporal mapping of important water quality parameters such as suspended sediment and chlorophyll (phytoplankton) concentrations are important for studying the effect Bonnet-Carrie spillway opening and also for proper management of Lake Pontchartrain waters. Traditional methods of quantification of these parameters only allow point measurements in space and time. On the other hand, remote sensing methods using air-borne and space-borne sensors have been useful for instantaneous and synoptic estimation of suspended sediment and chlorophyll concentrations. In this research, we will acquire daily coverage of medium resolution satellite data from Moderate-resolution Imaging Spectroradiometer (MODIS) sensor for suspended sediment and chlorophyll mapping. We will also discuss the performance of various well established band ratio algorithms used to map above water quality parameters. Spatio-temporal distribution of suspended sediment (organic and inorganic) and chlorophyll concentrations will be mapped in the Lake Pontchartrain before-during-after the event of Bonnet-Carrie spillway opening using MODIS data and band-ratio algorithms. The maps will be validated against field data collected during that period. We have acquired spectral reflectance data in two field trips after the spillway opening using Ocean-Optics hyperspectral spectro-radiometer. YSI probes were also used to quantify chlorophyll, phycocyanin and phycoerythrin pigments. Twenty six water samples were collected for suspended sediment analysis and pigment analysis. Suspended sediments were analyzed by gravimetric analysis and chlorophyll and other accessory pigments were analyzed using High Performance Liquid Chromatography (HPLC). The range of gravimetrically measured suspended sediments was found to be 13.3-26.6 mg/l. This work will be presented in the form of weekly time series maps of suspended sediments and chlorophyll concentrations distribution in the lake before and after the Bonnet-Carrie spillway opening.

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Nitrogen dynamics during and after storm events in the Mission-Aransas National Estuarine Research Reserve Rae Mooney and James W. McClelland. The University of Texas at Austin, Marine Science Institute, Port Aransas, Texas.

Nitrogen loading is important to coastal systems because primary production is often limited by nitrogen availability in estuarine/marine waters. Flux of freshwater or lack thereof is important because salinity influences the biological community structure and biogeochemical cycling in estuaries. During storm events, rivers deliver disproportionate amounts of water and nitrogen to estuaries. In South Texas, where precipitation is highly variable within and between years, a few major storm events each year account for a high percentage of annual river export. Concentrations of nitrate, ammonium, and dissolved organic nitrogen were determined in water samples collected at sites along the Aransas River and in Copano Bay during and following two major storm events in early and late July, 2007. During the time from June 29 – July 28, 2007, Aransas River discharge accounted for 70% of 2007 annual river export. Typical flow conditions of 0.18 m3/s (median discharge) create an uncoupling of the river and bay due to extremely low flow and an extensive tidal freshwater section with a long residence time in the lower portion of the river. However, during storm events the river delivers large pulses of freshwater and nitrogen to the bay. On July 5, the Aransas River discharge peaked at 227.1 m3/s, which is in the 99.97th percentile of the last 20 years of data. Following this event, a second smaller event peaked on July 24th, 2007 at 37.1 m3/s, in the 99.25th percentile. After these events salinity in Copano Bay dropped from 12 to 2 psu within 5 days and did not reach pre-storm salinity conditions again until December.

During and following these storm events nitrate concentrations upstream in the Aransas River exhibited a negative correlation with river discharge. Ammonium and dissolved organic nitrogen show a positive relationship with river discharge. As a result of increased discharge, export of nitrate, ammonium, and dissolved organic nitrogen from the Aransas River increased dramatically during these events. Nitrate and ammonium concentrations in the bay increased substantially immediately after each storm event, but showed different patterns of subsequent recovery. Nitrate decreased rapidly while ammonium was more variable and decreased more slowly. Dissolved organic nitrogen decreased immediately after the first storm event and then increased to concentrations greater than pre-storm values within a week. Subsequent recovery of dissolved organic nitrogen to pre-storm values occurred gradually over the summer. Although the entire bay showed a large salinity response, variations in nitrogen concentrations associated with the storm events decreased with increasing distance from the river mouth. This may, in part, reflect the fact that sampling at stations farther from the river mouth was initiated a few days after sampling began closest to the mouth (i.e. dynamics directly after the storm were missed). Differences in nutrient chemistry of other freshwater sources contributing to the salinity decrease in the bay may also account for the observed gradient in nutrient response.

With increasing eutrophication due to changing land use and land cover, growing populations, and potential increases in storm events associated with global warming, it is important to understand how these variables interact to produce changes in nutrient export from watersheds and how the timing and magnitude of nutrient loads effect estuaries and the coastal ocean. This study of storm related nutrient effects is part of a two year study designed to improve our understanding of land-sea coupling in South Texas.

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Report on Seagrass Beds of Ruppia maritima and Halodule wrightii at Grand Bay National Estuarine Research Reserve, Mississippi Nica, C. and H.J. Cho, Department of Biology, Jackson State University, 1400 Lynch St., Jackson, Mississippi 39217

Coastal seagrass beds serve as essential food and habitat for waterfowl and aquatic animals, help improve water quality and protect shores by assimilating excess plant nutrients and toxins, buffering wave energy, and stabilizing sediments. Therefore, seagrass beds affect processes, evolution, and fates of coastal features such as estuaries, and their distribution, abundance, and composition are widely accepted as good indicators of aquatic environmental quality. The decline in coastal environmental quality is a major global conservation problem; and estuarine seagrass community is typically influenced by both anthropogenic and natural environmental disturbances. In Mississippi Sound, seagrass beds have reportedly declined > 50% since the 1969 Hurricane Camille. In addition, the more significant declines occurred in stable, climax community seagrasses such as Turtlegrass (Thalassia testudinum K.D. Koenig) and Manateegrass (Syringodium filiforme Kutzing), which have resulted in the increased relative abundance of opportunistic, pioneer species such as Wigeongrass (Ruppia maritima L.) and Shoalgrass (Halodule wrightii Aschers) in estuaries and along barrier islands of the northern Gulf of Mexico. These changes would accentuate the temporal and spatial fluctuations of SAV because areal coverage and distribution of the SAV beds dominated by R. maritima would change substantially from season to season and year to year. The high fluctuation and unpredictability of seagrass beds that shift in time and space will negatively affect the survival and reproduction of the animals that depend on the resources in the seagrass beds as well as their predators. We hypothesized that there were significant spatial and short-term fluctuations in the coverage of Ruppia/Halodule beds along the Mississippi coast. We tested the hypothesis using field data collected biannually at five sites in Grand Bay National Estuarine Research Reserve, Mississippi. Three-way ANOVA was used to analyze SAV depth distribution and abundance, which we surveyed along gradients of water depth and shoreline orientation.

The SAV community, which consisted of R. maritima and H. wrightii, displayed significant short-term changes in abundance and species dominance, largely attributed to changes in R. maritima abundance between summer and fall. Our results on site variation in SAV coverage suggest that shore orientation within the estuarine system might be a contributing factor to the spatial difference in the shallow estuary. The effects of Hurricanes Katrina and Rita in 2005 on the SAV community appeared to be minimal. Despite the significant SAV decrease observed shortly after the storm passages, both species increased fast and significantly in 2006 in the estuarine area. However, the 2005 hurricanes resulted in loss of R. maritima (approximately 5 acres) in Bayou Cumbest due to physical disturbance and toxic pollutants released from damaged camps and residential properties. Ruppia maritima was the only submerged vegetation species that occurred in the bayou prior to the hurricanes; and the recovery of R. maritima in the bayou was delayed (> 2 years) and limited, probably due to the lack of a viable seed bank and remoteness from the estuarine source populations.

Estuarine Ruppia maritima produces an enormous number of seeds (several thousands to tens of thousands seeds per square meter) that are protected by sturdy seed coats. Desiccated seeds can stay viable for an extended period, and be broadcast into the field in a large amount in a short period of time. On the other hand, R. maritima that occurs in streams, marsh ponds, and bayous rarely flowers and sets seeds. Because of the nearly 100% dependency on asexual reproduction by R. maritima in Bayou Cumbest and the lack of appropriate water currents to facilitate fragment dispersal, restoration in the bayou requires human assistance.

We recently have initiated a restoration effort to revegetate the bayou using laboratory grown seedlings. Propagation of R. maritima from seeds would provide a time-, labor-, and cost- effective means of SAV restoration because this pioneer species would modify the habitat conditions to be favorable for numerous aquatic organisms. Promotion of SAV growth will enhance overall coastal restoration by increasing sedimentation rates, reducing sediment erosion rates, and providing essential habitat for fish and waterfowl.

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The Gulf of Mexico Coastal Ocean Observing System Nowlin, W. D., Jr.1, A. E. Jochens1. 1GCOOS Office, Department of Oceanography, 3146 TAMU, College Station, TX 77843-3146.

The Gulf of Mexico Coastal Ocean Observing System (GCOOS) is a System of Systems. It is comprised of many systems (operational elements) operated by separate entities and funded by a variety of sources. Yet to realize maximum benefit, the whole must operate as one; so it must be planned, coordinated, and managed as a system. It is the GCOOS Regional Association (GCOOS-RA) that plans, coordinates, and manages the system of systems that is GCOOS.

The GCOOS produces data and products in response to user requirements within the seven broad objectives of the U.S. Integrated Ocean Observing System (IOOS): 1. Detecting and forecasting oceanic components of climate variability; 2. Facilitating safe and efficient marine operations 3. Ensuring national security 4. Managing resources for sustainable use 5. Preserving and restoring healthy marine ecosystems 6. Predicting and mitigating against coastal hazards; and 7. Ensuring public health.

The first strategic objective of the observing system is to establish and maintain an active, strong, and effective organizational structure. Based on a Mission Statement, the GCOOS-RA was formed by a Memorandum of Agreement (MOA) which dictates the governance structure schematically shown in Figure 1.

Figure 1. Schematic of the structure of the GCOOS-RA as specified in the GCOOS Memorandum of

Agreement.

The Parties to the MOA elect a GCOOS Board of Directors that elects its own executive Committee. Since completing the organizational Structure in 2006, the RA has prepared a Conceptual Design, an Observing System Plan, a Communication Strategy, and Education and Outreach Strategic Plan, and a draft Business Plan. A Data Management and Communication Plan and revised Business Model are in progress.

The GCOOS-RA coordinates, plans for, and manages the GCOOS system of systems; it coordinates/integrates that system with other elements of the U.S. Integrated Ocean Observing System

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(especially the Southeast Coastal Ocean Observations Regional Association and the Caribbean Regional Association) and ocean observing systems of other nations producing data and products relating to the Gulf of Mexico; and it represents the GCOOS in the National Federation of Regional Associations (NFRA). GCOOS-RA coordinates with the Gulf of Mexico Alliance (GOMA), which is an alliance of the U.S. Gulf States Governors that is identifying state needs and attempting to solve them with assistance from federal agencies.

A key element of GCOOS's strategy is to identify and prioritize the needs of regional stakeholders for marine data and products. This identification and prioritization is proceeding in an incremental fashion. The initial planning meetings were composed mainly of data/model providers at the federal and local level. These were followed by a series of workshops, beginning with one mainly focused on state agencies and then by an IOOS-Industry workshop, a workshop on underpinning research, a workshop for the formation of an Educational and Outreach Council workshop, a workshop for the oil, gas and related industries, a workshop for users of storm surge and inundation information, and two workshops dealing with the detection and forecasting of harmful algal blooms. The entire sequence of meetings with reports is documented via the GCOOS web site (http://www.gcoos.org).

Additional focused stakeholder workshops in development or planning include two workshops (jointly sponsored with GOMA to further develop a Gulf of Mexico Harmful Algal Bloom Integrated Observing System Plan), two workshops focused on recreational boating activities, a workshop on ecosystem modeling, and workshops on marine transportation and urban planning and development.

The GCOOS-RA regularly identifies extant data and product providers who may support regional stakeholder needs. We are in the process of developing a GCOOS Data Portal to make non-proprietary data and products from the system of systems available to all users in machine interoperable form. This data portal is a key step in developing a Regional Operations Center from which all users can obtain real-time information on all operating systems.

It is a part of our strategy to develop plans for regional observing systems, models, and analyses to more fully meet the identified data and product needs of stakeholders. As we obtain a more complete inventory of those needs with priorities, we are able to modify our strategic design to more fully meet those needs. Then our approach is to compare those plans with inventories of extant systems to create an integrated requirement for enhancements (i.e., an analysis of gaps in our extant system of systems).

A key strategic element for the RA is to develop and maintain useful and effective education and outreach activities to support other strategic plan elements and raise more general awareness of the marine environment as well as of the IOOS. To this end we have a very active Education and Outreach Council supported by a full-time Education and Outreach Coordinator and we attempt to reserve 10% of all financial support garnered for use in education and outreach activities.

Finally, the GCOOS-RA strives to obtain funding to continue extant activities and to establish and maintain needed enhancements to observing systems. What are the reasons for establishing GCOOS and its RA? That is, what will GCOOS and its RA bring about that would not happen in their absence? • They will develop user requirements for the region. Identifying and serving local and regional user

requirements that otherwise would not be provided will expand system advocates. • They will enable easy access to data and model outputs that otherwise would not be readily or easily

accessible. The regional operations center will provide a focus for access, user feedback, and correction of difficulties.

• They will ensure that data obtained via the system are based on calibrated/verified instruments, have been quality controlled, and are accompanied by metadata adequate to allow evaluation and reasonable use.

• They will provide a mechanism to coordinate responses to events. Having an understanding of what GCOOS and its RA can bring to the community of data and product users, we ask "What are the reasons why operators of observing system elements would wish to join GCOOS?" • It will facilitate distribution of data from system elements to a much wider group of users than otherwise

might have access or be willing to search to find the data. • It will provide additional data to the primary users of data from the elements.

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• It will provide standards and protocols for data management that will provide consistency between elements and that will allow ease of access and utilization of data from the elements.

• It will provide a seal of approval to the data and products produced by the participating observing element. • For real time data, it can provide QA/QC and possible liability protection for data providers. • It assist with provision of resources for measurement enhancements or maintenance of elements. • It can provide to the observing system elements information on what enhancements and expansions their

users wish to have.

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Lake Pontchartrain fishery-independent data and the 2008 Bonnet Carré Spillway opening: a comparison of historic and post-opening surveys (oral presentation). O’Connell, M.T.,1,2 A.M.U. O’Connell1, B. Lezina3, C.S. Schieble1, and J.M. Van Vrancken1. 1 Pontchartrain Institute for Environmental Sciences, University of New Orleans, LA 2 Department of Earth and Environmental Sciences, University of New Orleans, LA 3 Louisiana Department of Wildlife and Fisheries, Baton Rouge, LA. The 2008 Bonnet Carré Spillway opening brought freshwater from the Mississippi River into the southwestern portion of Lake Pontchartrain, an oligohaline estuary. In a collaborative effort to assess how estuarine fish species responded to this inflow of river water, biologists with the Nekton Research Laboratory at the Pontchartrain Institute for Environmental Sciences and the Louisiana Department of Wildlife and Fisheries combined efforts to sample six Lake Pontchartrain sites using trawls on a weekly basis from April to June, 2008. This is the first time that such a large-scale ecological analysis of fishes has been attempted after a Spillway opening and the first time that historic fishery-independent data from 2000-2007 were available for comparative purposes.

When fish assemblages collected from April 2008 were compared with those collected in April in past years (2000-2003 and 2005-2007), post-opening collections were significantly different from 2001 (ANOSIM, p = 0.01), 2005 (ANOSIM, p = 0.04), and 2006 (ANOSIM, p < 0.01) collections. April 2008 collections were not significantly different from those in April 2002, 2003, or 2007. For collections made in May, the 2008 collections were significantly different from 2001 (ANOSIM, p = 0.03), 2002 (ANOSIM, p < 0.01), and 2006 (ANOSIM, p < 0.01) collections. Post-opening collections were not significantly different from those in April 2003, 2005, or 2007. The June collections yielded the most number of significant differences between 2008 fish assemblages and the historical data. June 2008 collections were significantly different from 2001 (ANOSIM, p < 0.01), 2002 (ANOSIM, p < 0.01), 2003 (ANOSIM, p < 0.01), 2006 (ANOSIM, p = 0.01), and 2007 (ANOSIM, p = 0.04) collections. Only collections made in June 2005 were not significantly different from June 2008.

We interpret these results as representing a delayed response by the fishes as the amount of river water in Lake Pontchartrain increased over time. The Spillway opened on 11 April 2008 and remained open for 31 days. When we began sampling in the latter half of April, much of the river water had yet to reach most of our sites, especially on the east side of the Lake. By May, there was more river water in the estuary but some sites on the east side retained typical spring salinities and fish assemblages. The significant differences in June 2008 collections, though, likely reflect fishes at all six sites finally responding to Lake-wide effects as the river water moved through the estuary and out towards the Gulf of Mexico. The mobility of most estuarine fish species allows them to respond to changing abiotic conditions and avoid potentially harmful stressors such as changes in salinity or temperature. For example, a large and rapid discharge of river water into and estuary is more likely to cause fish mortality versus a smaller, more gradual release.

Our results suggest that the significant changes in estuarine fish assemblages we observed may be avoided if planned releases of river water allow for more efficient mixing of water in the estuary. To further emphasize this point, we hope to examine these assemblage changes on a site-by-site basis such that the response of fishes closer to the Spillway can be compared to those on the eastern side of Lake Pontchartrain.

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Summary of Louisiana Coastal Protection and Restoration (LACPR) Planning Unit 1 (Pontchartrain Basin) Alternatives Padgett, C. US Army Corps of Engineers, Engineering Research Development Center, Environmental Laboratory, Geospatial Data Analysis Facility, 3909 Halls Ferry Rd., Building 1006, Vicksburg, MS 39180

The objectives of the Louisiana Coastal Protection and Restoration (LACPR) effort are to reduce overall risk to people, economic assets, coastal resources, and cultural resources along the Louisiana coast from storm events. Storm risk reduction measures can be formulated in two ways: either by reducing the probability of adverse consequences from the occurrence, or by reducing exposure to the occurrence; thereby reducing the consequences themselves. No alternatives have been formulated that will provide absolute protection over the entire planning area against all potential storms. One assumption used is that hurricane risk reduction plans should rely on multiple lines of defense. This strategy involves using natural features such as barrier islands, marshes, and ridges to complement engineered structures such as highways, levees, and raised homes. Within the context of a multiple lines of defense or comprehensive system, numerous risk reduction measures can be combined to form alternative plans. Each type of measure provides unique opportunities to develop comprehensive solutions to the flooding and habitat loss problems of the Louisiana coast. These combined approaches produce a multiple lines of defense system against storm surge. For the LACPR effort: • Coastal restoration alternatives, consisting of hundreds of coastal restoration measures, are the foundation of every alternative, with exception to the no action alternative. Examples of coastal restoration measures include land/marsh-building river diversions, freshwater redistribution, mechanical marsh creation, barrier island/shoreline restoration, bank/shoreline stabilization, and ridge restoration. • Structural measures and alternatives reduce flood risk using features that are designed to withstand the forces of storm events, such as surge-reduction weirs, floodgates, continuous earthen levees, floodwalls, and ring levees. • Nonstructural measures and alternatives reduce the exposure to risk by removing vulnerable populations and assets from the threat through measures such as buyout of properties or raising structures in place. Additional nonstructural measures include wet and dry flood-proofing of critical facilities. • Comprehensive alternatives (not to be confused with the comprehensive plan for the coast) refer to plans that contain all three types of risk reduction measures— nonstructural, structural, and coastal restoration—presenting a multiple lines of defense strategy, providing comparable levels of risk reduction to all economic assets in the surge impacted area.

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Impact of Cold Temperatures on Early Life History Stages of Black Mangrove (Avicennia germinans (L.) L.): Implications for Restoration Pickens, C.N. and Hester, M.W. Coastal Plant Ecology Lab, Department of Biology, University of Louisiana at Lafayette.

Globally, mangrove plant communities are a major component of barrier islands, headlands, and coastal salt marshes and provide human resources, biogeochemical, and ecological function. The range of Avicennia germinans (L.) L. (black mangrove) is thought to be limited by the occurrence of periods of freezing temperatures. In Louisiana, USA, A. germinans grows at its North American latitudinal limit within coastal salt marshes and back barrier island salt marshes. In the face of rising sea level and subsidence, A. germinans is a particularly valuable woody coastal plant species in Louisiana because of its potential to stabilize and trap sediment with complex root networks. Use of A. germinans for successful restoration of the Louisiana coastal plant communities relies on a thorough understanding of the impacts of cold temperature exposure on the early life history stage forms utilized for restoration.

To assess low temperature thresholds of A. germinans, we assessed the response of three early life history stages (dispersal stage, propagules floating in artificial salt water; stranded stage, propagules stranded on wet sand; and seedling stage, seedlings established in wet sand) to three temperatures (5.7, 2.5, and -6.75 °C) for four different durations (2, 6, 12, and 24 hours). Propagules and seedlings were of Louisiana origin (Caminada-Moreau Headland). The temperatures and durations were chosen to be representative of cold temperature exposure typical of coastal Louisiana. After experimental exposure, dispersal stage propagules were placed on wet sand. All individuals were allowed to recover in a greenhouse for eight weeks and were monitored for survival. Propagules were also monitored for developmental progress including radical emergence, establishment (radical rooted and cotyledons lifted off of the substrate), and presence of first true leaves. Survival analysis, which measures the risk of an event occurring over time, was performed on time until death and developmental progress. A Generalized Linear Model was used to analyze the proportion of dead plants at the termination of the experiment.

Temperature, duration of cold temperature exposure, and the interaction of these variables influenced the proportion of dead individuals at the termination of the study. Early life history stage did not significantly influence proportion of dead individuals. In support of this finding, survival analysis indicated that the risk of death during the study was not different among life history stages. However, a decrease in temperature and an increase in duration of cold temperature exposure increased the risk of death for propagules. Time until propagules attained later developmental stages was not influenced by temperature or duration of cold temperature exposure. Furthermore, propagules in the dispersal stage may have an advantage over propagules in the stranded stage because their risk of getting fungus during the recovery period was not significantly influenced by temperature or duration of cold temperature exposure.

These results support the use of propagules for salt marsh and back-barrier marsh restoration since their chances of survival appear no different from seedlings, and propagules are much easier to transport and cost less than seedlings. Propagules in the dispersal stage may gain a benefit by being insulated by ice during a freeze event. This study also demonstrates that a short term freeze event has long lasting effects on the Louisiana A. germinans population, thus evaluation of survival would be misleading immediately following the freeze event.

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The Relationship Between Environmental Characteristics And Invasive Fish Species In Oligohaline Coastal Tributaries Of Galveston Bay During Summer Months

Ramirez, Dianna1 and George Guillen1. 1University of Houston Clear Lake, Environmental Institute of Houston, 2700 Bay Area Blvd, Houston, Texas 77058. [email protected] 281-283-3950

The introduction of invasive species into the United States has become a major environmental and economic problem. Invasive fish species have been documented in coastal tributaries in Texas and are spreading into more waterways. Previous studies conducted by Texas Parks and Wildlife Department found invasive fish in larger bayous. Based on previous research invasive cichlids are also spreading throughout the Galveston Bay system. The presence of invasive species in smaller, non-navigable streams in the Clear Lake watershed has not been investigated. The first objective of our study was to examine the relationship between water quality and invasive fish species. The second objective of this study was to examine the relationship between invasive fish and native fish by comparing invasive fish abundance and native fish abundance.

The affect of human disturbance in the Clear Lake watershed is evident by examining the amount of development within the watershed. The channelization of streams in the study area is typical of urban coastal waterbodies throughout the Galveston Bay watershed. We observed decreased amounts of in stream vegetation in these channelized streams. Several of the coastal streams were dominated by return flows from wastewater treatment plants and urban runoff. Rio Grande cichlids (Cichlasoma cyanoguttatum) and Tilapia (Oreochromis spp.) were collected from all streams sampled. Rio Grande cichlids and Tilapia were the 5th and 8th most abundant species collected. Due to the abundance of Rio Grande cichlids, a range extension is suggested to include the Clear Lake watershed. The presence of invasive cichlids for seine collections was negatively correlated with overall fish community diversity, and evenness; whereas the presence of the invasive cichlids was negatively correlated with fish community diversity, evenness and richness for the electroshocking samples. The streams within the Clear Creek watershed had higher centrarchid abundances and higher fish community richness than those in the Armand Bayou watershed.

There is a need for continued research on invasive fish species within the Clear Lake and Galveston Bay watersheds. Long term and seasonal studies could tell us more about how and when the invasive fish are affecting the native fish community. Controlled laboratory studies should also be conducted to determine how cichlids affect centrarchids growth. In addition, monitoring of the smaller, wadeable tributaries and bayous on a regular basis is necessary in order to determine the spread of invasive species and ultimately in being able to control nonnative fish invasions. More education aimed at pet store owners, aquarium fish hobbyists and live food fish markets is needed to reduce the likelihood of future introductions.

References Clinton, W.J. (1999) Executive order 13112—Invasive species. Weekly Compilation of Presidential

Documents; 2/8/99, 35, 185-189. Coblentz, B.E. (1993) Invasive ecological dominants: Environments boar-ed to tears and living on

burro-ed time. In: Biological Pollution: The Control and Impact of Invasive Exotic Species (ed. McKnight) pp. 223-224. Indiana Academy of Science. Indianapolis.

Courtenay, W.R. (1993) Biological pollution through fish introductions. In: Biological Pollution: The Control and Impact of Invasive Exotic Species (ed. McKnight) pp. 35-61. Indiana Academy of Science. Indianapolis.

Courtenay, W.R., D.A. Hensley, J.N. Taylor, & J.A. McCann. (1984) Distribution of exotic fishes in the continental United States. In: Distribution, Biology, and Management of Exotic Fishes (eds. W.R. Courtenay & J.R. Stauffer) pp.41-77. The Johns Hopkins University Press. Baltimore.

Gido, K.B. & Brown, J.H. (1999) Invasion of North American drainages by alien fish species. Freshwater Biology, 42, 387-399

Howells, R.G. & Garrett, G.P. (1992) Status of some exotic sport fishes in Texas waters. The Texas Journal of Science, 44, 317-324.

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Howells, R.G. & Rao, J.B. (2003) Prohibited exotic fishes, shellfishes, and aquatic plants found by Texas Parks and Wildlife personnel in Harris County, Texas: 1995-1996 and 2001 through mid 2003. Texas Parks and Wildlife Management Data Series No. 218.

Kolar, C.S. & Lodge, D.M. (2002) Ecological predictions and risk assessment for alien fishes in North America. Science, 298, 1233-1236.

Martin, R.T. (2000) Range extension for Rio Grande cichlid Cichlasoma cyanoguttatum (Pisces: Cichlidae) in Texas. The Texas Journal of Science, 52, 173-175.

Meador, M.R., L.R. Brown, & T. Short. (2003) Relations between introduced fish and environmental conditions at large geographic scales. Ecological Indicators, 3, 81-92.

Monaco, M.E., D.M. Nelson, T.E. Czapla, & M.E. Pattillo. (1989) Distribution and abundance of fishes and invertebrates in Texas Estuaries. ELMR Rpt. No. 3.Strategic Assessment Branch, NOS/NOAA. Rockville, MD. 107 p.

Nico, L.G. & Martin, R. T. (2001) The South American suckermouth armored catfish, Pterygoplichthys anisitsi (Pisces: Loricariidae), in Texas, with comments on foreign fish introductions in the American Southwest. The Southwestern Naturalist, 46, 98-104.

[OTA] Office of Technology Assessment, (1993) Harmful non-indigenous species in the United States. Washington D.C.: Office of Technology Assessment, U.S. Congress.

Peterson, M.S., W.T. Slack & C.M. Woodley. (2005) The occurrence of non-indigenous Nile tilapia, Oreochromis niloticus (Linnaeus) in coastal Mississippi, USA: ties to aquaculture and thermal effluent. Wetlands, 25, 112-121.

Pimentel, D., L. Lach, R. Zuniga, & D. Morrison. (2000) Environmental and economic costs of nonindigenous species in the United States. Bioscience, 50, 53-65.

Pusey, B.J., M. J. Kennard, J.M. Arthur & A. H. Arthington (1998) Quantitative sampling of stream fish assemblages: Single- vs. multiple-pass electrofishing. Australian Journal of Ecology, 23, 365-374.

Robinson, L. & Culbertson, J. (2005) A synoptic survey for non-indigenous ichthyofauna in selected tidal bayous of Galveston Bay. Texas Parks and Wildlife Department, Coastal Fisheries Division, Dickinson Marine Laboratory.

Stauffer, J.R. (1984) Colonization theory relative to introduced populations. in: Distribution, Biology, and Management of Exotic Fishes (eds. W.R. Courtenay & J.R. Stauffer) pp.8-21 The Johns Hopkins University Press. Baltimore.

Taylor, J. N., W.R. Courtenay, & J.A. McCann. (1984) Known impacts of exotic fishes in the continental United States. in: Distribution, Biology, and Management of Exotic Fishes (eds. W.R. Courtenay & J.R. Stauffer) pp.322-373. The Johns Hopkins University Press. Baltimore.

[TPWD] Texas Parks and Wildlife Department, Fisheries, (2001) Harmful or potentially harmful exotic fish, shellfish, and aquatic plants. Texas Parks and Wildlife Code, chap. 66, subchap. A, § 66.007 accessed 04/15/2006 at http://www.ntwgs.org/articles/Revised_Exotic_Species_Rules_20.doc. http://www.tpwd.state.tx.us/huntwild/wild/species/exotic/ accessed 4/1/2008 http://info.sos.state.tx.us/pls/pub/readtac$ext.ViewTAC?tac_view=5&ti=31&pt=2&ch=57&sch=A&rl=Y

Traxler,S. L. & Murphy,B. (1995) Experimental trophic ecology of juvenile largemouth bass, Micropterus salmoides, and blue tilapia, Oreochromis aureus. Environmental Biology of Fishes, 42, 201-211.

Trimm, D.L., G. Guillen, C.T. Menn, & G.C. Matlock. (1989) The occurrence of grass carp in Texas Waters. The Texas Journal of Science, 41, 413-417.

Welcomme, R. L. (1984) International transfers of inland fish species. In: Distribution, Biology, and Management of Exotic Fishes (eds. W.R. Courtenay & J.R. Stauffer) pp.22-40. The Johns Hopkins University Press. Baltimore.

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Characterization of Benthic Invertebrate Communities of the Southern Lake Pontchartrain Shoreline, Summer 2007 Gary L. Ray,1 Elizabeth Behrens.2 1U.S. Army Engineer Research and Development Center, 3909 Halls Ferry Road, Vicksburg, MS 39180, 2 US Army Corps of Engineers, New Orleans, P.O. Box 60267, New Orleans, LA 70160.

The U.S. Army Corps of Engineers is considering various options for enhancing shore protection of the Lake Pontchartrain shoreline adjacent to the city of New Orleans. This work reports on a characterization study of benthic invertebrate communities in this area performed to assist in evaluation of potential construction impacts.

In July 2007, 26 sampling sites were established at approximately 1 mile intervals from Duncan Canal to 1 mile east of the Norfolk Southern Railroad causeway. Sampling stations within each site were established at distances of 100 ft (30.5 m), 500 ft (152.5 m), and 1,000 ft (305 m) from the waters’ edge using a handheld laser range-finder. Each station was sampled for benthic macroinvertebrates, sediment grain size distribution, and sediment organic content using a Ponar Grab sampler (0.04 m2). Standard water quality measures (temperature, salinity, and dissolved oxygen concentration) were also measured in the surface and bottom waters of each station.

Infaunal samples were rinsed in the field over a 0.5 mm screen, fixed and stored in a four percent buffered formalin solution. After transport to laboratory facilities infaunal samples were stained with Rose Bengal, and stored in 70% ethanol. Samples were subsequently examined using 3X illuminated magnification and organisms sorted from the sediments then identified to the lowest practical identification level and counted. Sediments were analyzed for total organic content by wet upon ignition and for grain size by a combination of wet sieving and pipette analysis.

Values for water quality parameters were relatively consistent across the shore. Differences in temperatures averaged less than 0.5 oC among stations or between the surface and bottom waters. Differences in salinity averaged less than 1.5 ppt among stations and less than 0.2 ppt between the surface and bottom waters, while average dissolved oxygen concentrations varied less than 1.2 mg/l among sites and less than 0.6 mg/l between surface and bottom waters.

The distribution of sediments varied along the shoreline with peat dominating the westernmost sites and fine and very fine sands dominating in the east. Sandy mud and muddy sand were most frequently found at stations the furthest from shore.

The benthic assemblage encountered along the lake’s shoreline was similar to that reported from open-water sites (e.g. Sikora and Sikora 1982, Junot et al. 1983, Poirrier et al. 1984, Poirrier et al. 1992, Pedalino 1999). Offshore assemblages have previously been reported to be dominated by molluscs including the gastropods Texadina sphinctostoma and Probythinella louisiana and the bivalves Rangia cuneata, Macoma mitchelli, Mulinia pontchartrainensis and unidentified mactrid clams. Other dominant species include the polychaetes Hobsonia florida, Mediomastus (LPIL), and Streblospio benedicti, the amphipods Ameroculodes miltoni, Apocorophium lacustre, and Cerapus benthophilus and the mysid Americamysis (=Mysidopsis) alymyra. Assemblages detected in the current study include all of the dominant open-water species except the gastropod P. louisiana. While no live specimens of this species were collected in shoreline samples numerous dead shells were present, suggesting that it may occur in this habitat.

The primary difference between open-water and shoreline assemblages appears to be the relatively high abundances of pericarid crustaceans including the amphipods A. lacustre, Grandidierella bonneroides, C. benthophilus, A. miltoni and Lepidactylus dytiscus, the tanaid Hargeria rapax, and the cumacean Alymyracuma (LPIL), as well as three polychaetes, Polydora cornuta, Parandalia americana, and Capitella (LPIL). All of these taxa except Lepidactylus have been reported from other Lake Pontchartrain studies, but not in the abundance found along the shoreline. The primary determinant of this pattern appears to be sediment type. The amphipods A. miltoni and L. dytiscus, and the cumacean Alymyracuma, are all associated with sandy substrates, a sediment type under-represented in previous studies. Likewise, all of the remaining species except for P. americana are most abundant in peat substrate, a sediment type for which there are no previous reports. Species

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dominant in open-water assemblages and present but not dominant in shoreline samples include the gastropod Texadina sphinctostoma, the isopod Cyathura polita, chironomid fly larvae, the mussel Mytilopsis leucophaeata, and oligochaetes.

Reference Cited

Junot, J. A., M. A. Poirrier, and T. M. Soniat. 1983. Effects of saltwater intrusion from the Inner Harbor Navigation Canal on the benthos of Lake Pontchartrain. Gulf Research Reports 7, 247-254. Louisiana Wildlife and Fisheries Commission 1976. An inventory and study of the Lake Pontchartrain - Lake Maurepas estuarine complex. Technical Bulletin No. 19. Louisiana Wildlife and Fisheries Commission, Oysters, Water Bottoms and Seafoods Division, Baton Rouge, LA. Manheim, F.T., and Hayes, Laura, 2002, Sediment database and geochemical assessment of Lake Pontchartrain Basin, chap. J of Manheim, F.T., and Hayes, Laura (eds.), Lake Pontchartrain Basin: Bottom sediments and related environmental resources: U.S. Geological Survey Professional Paper 1634, 1 CD-ROM. Available online at http://pubs.usgs.gov/prof/p1634j/index.htm

Pedalino, F. M. 1999. Macrobenthic invertebrate community structure in Lake Pontchartrain’s “Dead Zone” following a summer algal bloom. University of New Orleans, Master’s Thesis.

Poirrier, M. A, T. M. Soniat, Y. A. King, and L. E. Smith. 1984. An evaluation of the southern Lake Pontchartrain benthos community. University of New Orleans. A report to the Louisiana Department of Environmental Quality, Office of Water Resources. Interagency Agreement No. 64003-85-05.

Poirrier, M. A., S. P. Powers, and Y. O. Yund. 1992. Effects of urban runoff on infaunal invertebrates in southern Lake Pontchartrain. Water Environment Federation 65th Annual Conference and Exposition, New Orleans, September 20-24, 1992. Pages 15-18.

Sikora, W. B. and B. Kjerfve. 1985. Factors influencing the salinity regime of Lake Pontchartrain, Louisiana, a shallow coastal lagoon: analysis of a long-term data set. Estuaries 8: 170-180. Sikora, W. B. and J. P. Sikora 1982. Ecological characterization of the benthic community of Lake Pontchartrain, Louisiana. Prepared for U. S. Army Engineer District, New Orleans. DACW29-79-C-0099 by Coastal Ecology Laboratory, Center for Wetland Resources, Louisiana State University, Baton Rouge, LA. United States Environmental Protection Agency 2007. Environmental Mapping and Assessment Program. Data downloads available at http://www.epa.gov/emap/

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Transgressive Evolution of the St. Bernard Shoals Rogers, Bryan and Mark Kulp. Department of Earth and Environmental Sciences, University of New Orleans, New Orleans LA.

Several shore-parallel marine sand bodies lie on the southeast Louisiana continental shelf (Figure 1). These shoals, Outer Shoal, Ship Shoal, Trinity Shoal and the St. Bernard Shoals, mark the position of ancient submerged shorelines associated with abandoned deltas. Three of these shoals are single elongate deposits. The fourth shoal, the St. Bernard Shoals, lying 25 km southeast of the Chandeleur Islands, consists of a group of discrete sand bodies ranging in size from 44km2 to 3km2,. The St. Bernard Shoals lie in 15-18 m of water and have as much as 3-5 m of relief. The strike of the larger individual sand bodies is shore normal (northwest-southeast), whereas the strike of the shoal platform is shore-parallel. The St. Bernard Shoals are stratigraphically above Frazier’s (1967) subdelta 9 of the St. Bernard delta complex. The development of the St. Bernard Shoals has important implications for the chronology of the St. Bernard delta complex, the future evolution of the Chandeleur Islands and models of transgressive submergence

For this study 47 vibracores and 400 km of shallow-surface seismic data collected across the Louisiana-Mississippi continental shelf in 1987 were analyzed. In June 2008, 384 km of seismic data and side scan imagery, and 8 sea-floor sediment grab samples were acquired across the study area and appended to the data set. Vibracores were analyzed then integrated with seismic profiles to identify facies and their regional distribution. A distributary channel map was created and two schematic geologic cross sections were developed, based upon vibracore interpretation, describing the distribution of 11 facies.

The results of this study indicate that a local transgression reworked available coarse-grained deltaic sediment into a barrier shore face deposit after abandonment of the delta. The barrier island then began to degrade and fragment, possibly due to high wave energy or high rates of tropical cyclone activity, similar to the processes affecting the Chandeleur Islands today. The barrier shore face then became submerged and an unidentified process caused secondary reworking and erosion of the St. Bernard Shoals. Side-scan imagery of the shoals shows the presence of sand-waves, scouring and slumping, suggesting that the deposits are still subject to reworking from the unidentified process.

The location of individual shoals is controlled by local availability of coarse grained sediment in the underlying deltaic deposit. The long-axes of the larger individual shoal bodies are oriented along distributary channels or other local sources of sand in the underlying deposit. The location of the shoal platform is also constrained by sediment availability. A large interterdistibutary bay to the southwest and a steep, narrow deltaic platform to the northeast confine the shoals to their present location.

The distributary channel network and seismic data suggest a continuous deltaic deposit from landward of the Chandeleur Islands to seaward of the St. Bernard Shoal. However, the depth of the shoals corresponds to the height of sea-level 9,000 years ago. The only other shoal on the Louisiana Continental shelf that occupies similar depth is Outer Shoal which formed 7,000 to 9,000 years ago (Penland et al., 1989). However, no age dates exist for the deltaic deposits seaward of the Chandeleur Islands.

References Cited Frazier, D. E., 1967, Recent deltaic deposits of the Mississippi River – their development and chronology:

Transactions of the Gulf Coast Association of Geological Societies v. 17, p. 287-315 Penland, S., Suter, J. R., McBride, R. A., Williams, S. J., Kindinger, J. L., Boyd, R., 1989 Holocene sand shoals

offshore of the Mississippi River delta plain: Transactions of the Gulf Coast Association of Geological Societies v. 39, p. 471-480.

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Figure 1: Location map of the Chandeleur Islands and the St. Bernard Shoals

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Community-led Urban Wetland Restoration in New Orleans’ Lower 9th Ward: The University of Wisconsin’s Biological and Social Science Characterization Ross, Ashleigh, Ashley Wallace, Ben Tansy, Dalayna Tillman, Andrew Leaf, Amanda Perzdock, Dan Cornelius, Hiroko Yoshida, Michelle Scott, The University of Wisconsin-Madison, 909 Spaight St. #1, Madison, WI, 53703

For the past two years the University of Wisconsin has been collaborating with the Holy Cross Neighborhood Association (HCNA) and residents of the Lower 9th Ward to restore the Bayou Bienvenue Wetland Triangle (BBWT) directly north of the Lower 9th Ward. This former cypress swamp has converted to open water in the past 50 years due to salt water intrusion. Immediately following Hurricane Katrina, the Lower 9th Ward identified the restoration of BBWT as an integral piece of their community’s redevelopment because of a cypress swamps’ storm protection, recreation and economic development opportunities.

HCNA and their planning and implementation arm, the Lower 9th Ward Center for Sustainable Engagement and Development (CSED) invited the UW team to characterize the wetland and the neighborhood’s relationship to it. A multi-disciplinary graduate team has collected 2 years of data on the hydrology of the wetland, land ownership issues, the neighborhood’s knowledge of restoration and uses of the bayou. With the collected data, the UW team is assessing the feasibility of various restoration options. Two proposals are currently being considered and the UW data has provided an independent evaluation from the perspective of community development. In the face of these multimillion dollar proposals it is imperative that the community is educated and knowledgeable about what kind of impact these projects could have on the social fabric of the neighborhood.

Strong community participation has set this restoration plan apart from the others. Another aspect of the UW work is to collaborate with HCNA/CSED in broad scale outreach and education within the Lower 9th Ward. HCNA/CSED has realized that for this restoration project to be successful, community support and buy-in is essential. In the vein, the UW team has a strong focus on neighborhood participation and involvement. As the restoration project pulls in big agencies such as the New Orleans Sewerage and Water Board and the Army Corps of Engineers’ Coastal Wetland Planning Protection and Restoration Act (CWPPRA) it is imperative that the community is armed with the knowledge to advocate for their own needs in the restoration. Much of the project focus is on citizen education. As this project gains momentum, it has become a model of community-based natural resource management.

The poster will highlight the community-led aspects of this project and outline the relevance to existing wetland restoration projects. Additionally it will provide background information on the current restoration proposals. The hydrology of the wetland will be graphed along with the toxicity and contamination information. Land ownership issues will be discussed and management options will be explored. The social science aspect will play a strong role in the poster with information about the history of BBWT, neighborhood uses and current knowledge of restoration. Drawing on our multi-disciplinary team, we will demonstrate the interconnectedness of the biological and social approaches that are necessary to properly address the community’s needs in restoration.

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Effects of seasonal hypoxia on harpacticoid copepod community structure in the northern Gulf of Mexico. Ryckman, L.Y.C.1, E.J. Buskey1, P.A. Montagna2. 1University of Texas Marine Science Institute, 2Texas A&M University Corpus Christi, Harte Research Institute Hypoxia (< 2 mg dissolved oxygen per liter) in the northern Gulf of Mexico has well documented lethal effects on benthic organisms. Less studied are the sub-lethal effects of low oxygen on benthic community structure. We studied the effects of low dissolved oxygen (DO) on population and reproductive characteristics of the harpacticoid copepod community in the sediments of the northern Gulf of Mexico. Harpacticoid copepods were studied because they brood their eggs and are known to be sensitive to low levels of DO. During cruises in summer and fall in 2007 and 2008, sediment cores were taken along 3 transects that differed in the amount of time they were exposed to low DO. From these cores we measured harpacticoid biomass, abundance, and the number of gravid females. Summer samples showed significantly higher abundance and species diversity at normoxic sites compared to hypoxic or intermediate DO sites. However, in the fall 2007 there was evidence of harpacticoid community recovery at some of the intermediate DO sites.

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Investigation of Sources of E. coli Isolated from Potential Oyster Harvesting Waters, Cedar Lakes, Texas Smith, A., J. Mott. Texas A&M University-Corpus Christi, Corpus Christi, TX

Cowtrap and Cedar Lakes are potential oyster harvesting waters. However, the 2004 Texas 303(d) list included the entire segment 2442 (Cedar Lakes) for bacteria. These water bodies are also classified as restricted from oyster harvesting by the Texas Department of State Health Services (TDSHS). In this study, bacteria source tracking (BST) was used to evaluate the sources of fecal contamination in the Cedar Lakes segment to provide data for use in future evaluations of this water body. The BST method utilized in this study, antibiotic resistance analysis (ARA), is a library-dependent method, requiring the use of a library of known source isolates to compare unknown isolates with. E. coli isolates were obtained from water samples provided by TDSHS from Cedar and Cowtrap Lakes from two sampling events in March (wet weather) and April (dry weather). The identities of the E. coli isolates were confirmed using carbon source utilization profiles generated with the MicroLog™ Microbial Identification System. Isolates confirming as E. coli were analyzed via ARA, following the Kirby-Bauer disk diffusion method outlined by the Clinical and Laboratory Standards Institute. Zone diameters from ARA profiles were analyzed with discriminant analysis using SPSS software (Release 15.0, 2006) and compared to those of the library of known isolates. Using a two-way classification (human vs. nonhuman), 91.3% of the 299 unknown isolates were categorized as nonhuman source, with 8.7% categorized as human source. Further breakdown divided these nonhuman isolates into two main groups—domesticated animals (cows and horses) (17.7%) and migratory birds (76.3%). A small percentage (1.7%) was attributed to miscellaneous wildlife (e.g. coyote, fox, raccoon).

Overall migratory birds seem to be responsible for the largest portion of the unknown E. coli samples isolated from the March and April water sampling events. This is consistent with the previously collected sanitary survey data that the peak populations of migratory waterfowl can reach up to tens of thousands at the adjacent 24,000 acre San Bernard Wildlife Refuge (TDH, 1990; TDSHS, 2008). The proportion of isolates classified as human vs. nonhuman source from water collected following a rain event did not appear to differ from that collected under dry conditions. Slight differences were found in the percentage of isolates classifying as human source; however, the limited number of isolates from each station (~50) precludes definitive conclusions. Based on this study, fecal contamination in Cedar and Cowtrap Lakes appears to be primarily of nonhuman origin, with a majority of water isolates identifying in the category of migratory bird. Recent increased awareness of health hazards associated with nonhuman (e.g. bird) contamination suggests this source of contamination is still a concern, particularly in potential shellfish harvesting waters. To gain a more complete picture of the nonpoint sources of fecal contamination of Cedar and Cowtrap Lakes additional sampling should be conducted throughout the year to elucidate seasonal effects.

References Texas Department of Health, 1990. Cow Trap Lake: A Study of Pathogens, Indicators, and Classification of a Texas Shellfish Growing Area Texas Department of State Health Services, 2008. Comprehensive sanitary survey of the shellfish producing waters of the Cow Trap and Cedar Lakes area. Texas Department of State Health Services, Seafood and Aquatic Life Group.

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The Future of Louisiana: Not a Model FROM the Netherlands but a Model FOR the Netherlands Natalie Snider1 and John W. Day2 1Coalition to Restore Coastal Louisiana, 6160 Perkins Road, Suite 225, Baton Rouge, Louisiana 70808 2Louisiana State University (Professor Emeritus) and Comite Resources, Inc.

The bond that formed in 2005 between the Netherlands and Louisiana is one over tragedy. The Flood of

1953 was a devastating event for the Dutch reminiscent of flooding that had reoccurred throughout the small country’s history. The hurricanes of 2005, specifically the failure of the levees during Hurricane Katrina, reminded the Netherlands of that devastating flood, which claimed the lives of 1,836 residents, left 89 holes in the dikes, inundated 770 square miles of land and destroyed or damaged 46,000 homes. The differences in storm types, protection levels and investments were equalized through the similarities in damage caused by these two storms.

The idea of controlling a flood is like trying to harness chaos in a bottle. Yet, throughout history, humans have continued to attempt and fail at this notion. Unlike earthquakes and tornadoes, we have been unwilling to accept the fact that we cannot dominate this force and thus, have been unwilling to learn how to live with it.

As a society worldwide, we have yet to realize that we do not have the ability to control floods. On the contrary, we believe that we can indeed eliminate the risk of flooding. Yet, so many of the decisions this society has made – large navigation channels, filling in wetlands (nature’s natural water storage), building our homes at-grade in vulnerable areas, and many more – have all occurred without consideration to its ultimate impact on flooding risks, thus inadvertently increasing the risk of more frequent and more destructive floods. Even in the Netherlands, a country that has united with flood protection as their #1 priority – Safety Above All Else – will flood again as they did in 1953.

Since the hurricanes of 2005, there has been an intense interest in the knowledge and capabilities of the Netherlands to provide a high level of protection. The Delta Plan, which was initiated and implemented after the Flood of 1953, is a feat of engineering and commitment. Portions of the Delta Plan are referred to as one of the seven wonders of the modern world by the American Society of Civil Engineers. It demonstrates the level of achievement that is capable when safety is the top priority.

The Dutch system is a combination of dunes, dikes, dams and storm surge barriers that have been constructed and improved over the past 1,000 years. In the process of trying to protect their small country and expand their economy, the Dutch developed all of their wetland areas. The protection system lies on the interface between the sea and the developed land. It is their first and only significant line of defense for a country where sixty percent of the population lives below sea level. The Dutch system is extremely energy and financially intensive and requires annual investments to maintain the system.

Even though the Dutch invest billions of dollars into their protection system, it is not feasible to endlessly heighten sea dikes. Figure 1 below illustrates that 83 percent of the dikes that were tested for armoring protection (which reduces the risk of failure) were doubtful or insufficient in 2006. In addition, approximately 30 percent of the dikes are below the height standard to withstand the acceptable overtopping rates without failure. In 2007, only 62 percent of the dikes met the safety standards for the country (Rijkswaterstaat Annual Report 2007).

The future threat for this country is intensified by global climate change. Global sea level rise of a meter or more in the 21st century means that the height of the dikes will have to increase extensively or the level of protection provided by those dikes will decrease.

The Dutch are not the only nations looking for solutions to their flooding problems. Com Coast is an international program developed by the Netherlands, United Kingdom, Belgium, Denmark and Germany. Com Coast’s aim is to move from a traditional single line of defense to a multi-functional defense zone. All of these nations have been battling flooding from the North Sea for thousands of years, but during that time, the method for protection has barely changed. Over the history of protection in these countries, the systems of dikes have failed repeatedly with devastating destruction and loss of life. Each time being rebuilt a little bit bigger and a little bit stronger.

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Figure 1. Results from the 2006 armoring test in the southern delta of the Netherlands. Distances shown in kilometers.

In Louisiana, the solution after Hurricane Katrina was to rebuild some of the levees in New Orleans a little bit higher and a little bit stronger. Many in Louisiana, including some of our leaders, have touted the Dutch’s high level of protection as a goal, an aspiration for Louisiana’s future. We should strive to provide the highest level of protection possible for our communities and we can achieve this with the tools we have available, however this should not rely on structural (levee) protection alone. Our wetlands, barrier islands, natural ridges are all a part of our Multiple Lines of Defense. In addition, we incorporate elevating homes and evacuation which protects the individual’s assets and family.

Louisiana has the resources it needs to rebuild the Multiple Lines of Defense and the ability to ensure that our protection, and not our risk, grows every day. These are the key differences that could put Louisiana in the position to lead the world in flood protection and provide a safe place to live and work for our grandchildren.

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Oyster Sentinel: monitoring oyster disease and the health of Gulf of Mexico estuaries Soniat, T.M.1, S.M. Ray2, L. Robinson3, P. Banks4, J. Supan5, B. Randall6, S. Powers7,M. Berrigan8, A. Volety9. 1Department of Biological Sciences, Lakefront, University of New Orleans, New Orleans, LA 70148. 2Department of Marine Biology, Texas A&M University at Galveston, Galveston, TX 77553, 3Texas Parks & Wildlife Department, 1018 Todville Rd., Seabrook, TX 77586, 4Louisiana Department of Wildlife and Fisheries, Marine Fisheries Division, Baton Rouge, LA 70806, 5Louisiana Sea Grant College Program, Louisiana State University, Sea Grant Building, Baton Rouge, LA 70803, 6Mississippi Department of Marine Resources, 1141 Bayview Ave., Suite 101, Biloxi, MS 39530, 7Dauphin Island Sea Lab, 101 Bienville Blvd., Dauphin Island, AL 36528, 8Florida Department of Agriculture and Consumer Services, Division of Aquaculture, 1203 Governor’s Square Blvd., Tallahassee, FL 32301, 9Florida Gulf Coast University, 10501 FGCU Blvd., Fort Meyers, FL 33965.

Oyster Sentinal is a web-based community which uses the eastern oyster, Crassostrea virginica, as a bioindicator of estuarine health. The community consists of shellfish scientists, resources managers and oyster growers from Texas, Louisiana, Mississippi, Alabama and Florida. Oysters are sampled (generally quarterly) from multiple stations in Corpus Christi Bay, Aransas Bay, San Antonio Bay, Matagorda Bay, Galveston Bay, Sabine Lake, Lake Calcasieu, Vermilion Bay, Caillou Lake, Terrebonne Bay, Barataria Bay, Breton Sound, Mississippi Sound, Mobile Bay, Apalachicola Bay, and Charlotte Harbor.

Oysters are assayed for Perkinsus marinus (=Dermocystidium marinum), a major cause of mortality to eastern oysters. The disease is more prevalent in larger oysters in warmer, saltier waters. The web site displays station information, water temperature and salinity, and percent infection and disease intensity of sub-market and market-sized oysters.

Oyster reefs are major components of estuarine systems of the Gulf of Mexico, and active reefs indicate that the system is suitable for many other estuarine-dependent species. The absence of oyster reefs in high salinity waters is due in part mortalities caused by P. marinus. Thus, information on the distribution of the parasite across the salinity gradient is essential to the restoration of oyster reef habitat. The oyster and its principal parasite are indicators of mesohaline salinity regimes, and their distributions can be used to evaluate the freshwater resources needed to sustain oysters, control parasites and support other estuarine-dependent organisms.

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Changes in Nutrient, Conductivity, and Chlorophyll a Following the Opening of the Bonnet Carré Spillway Risley, R.R.1; Voegel, P.D.1; J.D. Stricks1. 1Department of Chemistry & Physics, Southeastern Louisiana University, Hammond, LA 70402

Following congressional authorization in the Flood Control Act of 1928, The Bonnet Carré Spillway was designed and constructed in less than three years. The spillway is used to control flooding in the Mississippi River when extremely high waters and water flows pose an unacceptable risk to the downstream levee system by allowing the diversion of up to 250,000 cfs water into Lake Pontchartrain. The spillway has been used only nine times, most recently, in April 20081.

Six sites near the Bonnet Carré Spillway were selected for monitoring changes in nutrient, conductivity, and chlorophyll a levels. The monitoring program began just prior to the opening of the spillway on April 11th and beyond the closing of the spillway on May 8th. Sites were located at approximately 1 and 2 miles from the east and west ends of the spillway with additional sites to the east and west of the spillway in Lake Pontchartrain. Using GPS to locate sites, surface water grab samples were collected from each site eight times from April 11th through June 9th. Additional samples have been taken in August and September. Conductivity, pH, nitrate, phosphate, silicate, and chlorophyll a were measured for each sample using standard methods.

As expected, the initial conductivity at all sites was relatively high, ranging from 1650μS to 6700μS. The lowest levels of conductivity were observed at the three western-most sites due to low-flow seepage of Mississippi River water into the spillway prior to its opening. Conductivity remained high in the first few hours following the opening of the spillway, but decreased to less than 300μS at all six study sites by April 15th due to the infusion of freshwater from the Mississippi River. The conductivity slowly began to increase following the closing of the spillway, but had still not returned to the pre-opening levels as late as June 9th. By August, conductivity levels had increased to more than 5000μS at all study sites as expected for a brackish lake.

Prior to the opening of the spillway, nitrate concentrations, ranging from 0.3 – 1.2 ppmN with an average of 0.7ppmN, at the six sites were already low and decreased to non-detectable as the spillway was opened. However, by the fourth day after the spillway’s opening, nitrate concentrations increased to an average

concentration 1.4ppm N at the six sampling sites with a range of 0.8 – 2.1 ppmN and remained high until the spillway was closed. Higher levels of nitrates are expected in Mississippi River water compared to Lake Pontchartrain. Within one month of the closure of the spillway, nitrate concentrations had reached non-detectable levels. As shown in Figure 1, rapidly decreasing nitrate levels following the closure of the spillway correspond to increasing levels of chlorophyll a in the study area. As nitrate levels decreased to an average of 0.1 ppmN, chlorophyll a levels increased to 38.2 ppb. With depletion of nitrate, a rapid decrease in chlorophyll a levels occurred. By June 2nd, approximately 1 month after the closing of the spillway and approximately 1 week after depletion of nitrate near the spillway, the average chlorophyll a level had decreased to 3.5ppb. It should be noted that chlorophyll a levels did not

immediately increase with the opening of the spillway. It is hypothesized that the flow of water into Lake Pontchartrain pushed algae growing in response to increases in nitrate farther into the lake and outside the area monitored in this work, mitigating the growth of algae in the immediate vicinity of the spillway during its opening. http://www.mvn.usace.army.mil/pao/bcarre/bcarre.htm

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The 2008 Dinophysis bloom along the Texas coast: distribution and toxicity. Swanson, K.M. and T.A. Villareal. University of Texas Marine Science Institute, Port Aransas, Texas 78373.

Harmful algal blooms (HABs) are natural events that impact an ecosystem in ways people consider

undesirable, such as shellfish toxicity, water discoloration, fish kills, and anoxia. HABs can cause harm either through the production of toxins, the physical structure of a cell, or the accumulation of biomass that affects co-occurring species and can have effects within the trophic levels. Blooms occur globally throughout the oceans, but over the past decades the frequency and intensity of HABs in coastal waters has increased (Hallegraeff 1993; Glibert et al. 2005). Though this may be due to natural factors, such as species dispersal by wind or current, in many cases, human activities are suspected or known to be the cause (Glibert et al. 2005). While an increase in phytoplankton research and awareness could provide a more complete knowledge of occurrences and localities, anthropogenic effects are likely causing an increase in the events. Human related actions such as global climate change, population increase, nutrient loading, and increases in aquaculture and agricultural fertilizer use provide more favorable conditions for blooms to expand (Lam and Ho 1989; Glibert et al. 2005). While dispersal of resting cysts in ballast water, movement of mollusk stocks from one area to another, and an increase in man-made structures, such as marinas or oil rigs, aid in habitat expansion for HAB species (Vila et al. 2001; Glibert et al. 2005; Villareal et al. 2007).

In early 2008, oyster beds along the Texas coast were closed due to the threat of diarrhetic shellfish poisoning (DSP). This marked the first time both elevated concentrations of D. acuminata and DSP intoxicated shellfish had been detected in U.S. waters requiring shellfish beds to be closed to harvesting.

In past years, Dinophysis spp. had been reported in coastal waters off of Texas (Figure 1), though concentrations at bloom levels have never been detected. The Dinophysis bloom was initially detected by a particle imaging system (Imaging FlowCytobot) that combined video and flow cytometric technology to produce images for plankton identification and to measure chlorophyll fluorescence associated with each image (Campbell, per comm.). The coastline and interior bay distributions were monitored by traditional cell counts.

Figure 1: Absence or presence of Dinophysis spp. in MERHAB samples between 2000 and 2008. Mostly present during spring and fall months.

Samples collected by Texas Parks and Wildlife provided information on the offshore distribution of the

Dinophysis bloom. The stations showed Dinophysis cells at high concentrations up and down the Texas coastline (Figure 2). High concentrations of 11 and 26 cells/mL were first observed in the southern stations off

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Brownsville and Port Aransas (Rockport) in mid to late February. While cell abundance decreased through late February and early March at these southern locations, the northern stations off Port O’Conner and Sabine Pass increased to highs of 6 cells/ mL. High cell counts at both Brownsville and Rockport occurred near 17°C. In general there was a downward trend the farther away from 17°C (Figure 3).

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Figure 3: Dinophysis cells/mL plotted against temperature. Maximum cell counts were observed at 17°C.

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Inshore samples were taken throughout the Port Aransas area following bloom detection. In the bays,

few or no Dinophysis cells were observed. Cell counts from sites around the Port Aransas ship channel contained 34 and 11 cells/mL, but declined through April. The high cell numbers located offshore and within the ship channel, and the timing and magnitude of different peaks, support the idea that the Dinophysis bloom originated off the coast and moved inland. The offshore samples also provide information supporting that the bloom began in the southern Gulf, moving northward and inland.

Toxicity of water and cell samples were examined using a protein phosphatase inhibition assay. Okadaic acid (OA) and certain analogues (DTX1, DTX2) are an inhibitors of two major phosphatases in the cytosol of mammalian cells. The inhibition of protein phosphatases 1 and 2A ( PP1 and PP2A), results in a rapid accumulation of phosphorylated proteins (Bialojan and Takai 1988). In 1997, Vieytes and collaborators developed an assay using commercially available PP2A, 4-methylumbelliferyl phosphate (a fluorescent substrate), and a fluorescence plate reader. With a detection limit of 3.2 pg OA mL -1, this assay allowed for in house toxin analysis to be completed. Toxin samples were collected from surrounding bays following bloom detection. Toxicity was found to decrease as the D. acuminata cell numbers declined. One sampling site, Conn Brown Harbor showed a steep increase in toxicity at the end of the bloom. There were no obvious trends between toxicity and salinity or temperature. The D. acuminata bloom that occurred of the Texas coast in the spring of 2008, was a first for that region, and the co-occurring shellfish toxicity with closures was a first for the U.S. By understanding where this bloom originated and where it moved to allows for future determination of oyster bed closures. These oyster beds, which are often closed due to Red tides, are a vital part to the fisheries of Texas. Understanding when, why, and for how long these organisms would be tainted is imperative.

References Bialojan, C. & Takai, A. 1988. Inhibitory effects of a marine-sponge toxin, okadaic acid, on protein

phosphatases. J. Biochem 256:283-90.

Glibert, P. M., Anderson, D. M., Gentien, P., Graneli, E. & Sellner, K. 2005. The global, complex phenomena of harmful algal blooms Oceanography 18:136-47.

Hallegraeff, G. 1993. A review of harmful algal blooms and their apparent global increase. Phycologia 32:79-99.

Lam, C. W. Y. & Ho, K. C. 1989. Red tides in Tolo Harbour In Okaichi, T., Anderson, D. & Nemoto, T. [Eds.] Red Tides: Biology, Environmental Science and Toxicology Elsevier Science Publishing Co., New York, pp. 49-52.

Vieytes, M. R., Fontal, O. I., Leira, F., deSousa, J. & Botana, L. M. 1997. A fluorescent microplate assay for diarrheic shellfish toxins. Analytical Biochemistry 248:258-64.

Vila, M., Garces, E., Maso, M. & Camp, J. 2001. Is the distribution of the toxic dinoflagellate Alexandrium catenella expanding along the NW Mediterranean coast? Marine Ecology-Progress Series 222:73-83.

Villareal, T. A., Hanson, S., Qualia, S., Jester, E. L. E., Granade, H. R. & Dickey, R. W. 2007. Petroleum production platforms as sites for the expansion of ciguatera in the northwestern Gulf of Mexico. Harmful Algae 6:253-9.

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Age and growth of the littlehead porgy, Calamus proridens, from the central west coast of Florida Tyler, A.J. 1and R. Lehnert2. 1 Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 100 8th Avenue SE, St. Petersburg, FL 33701 2 Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 350 Carroll St. East Point, FL 32328

The littlehead porgy, Calamus proridens, is an important component of the nearshore/offshore fish assemblage found in the eastern Gulf of Mexico, however, specific life history information is not well known. Other members in the genus Calamus spp, (Sparidae) are known to be sequential hermaphrodites, and recent work has shown C. proridens to be protogynous hermaphrodites. In this study we collected 1,814 C. proridens ranging from 76mm – 361mm fork length (FL) from the north/central west coast of Florida between 2000-2007. Females ranged between 76-297mm FL (mean FL=159mm, n=1420), males ranged between 141-361mm FL (mean FL=244mm, n=297), and transitionals ranged from 131-307mm FL (mean FL=207mm, n=42). Sex ratios (4.6:1.0 female) were significantly different (p<0.0001). Sagittal otoliths (sectioned and whole) from 1,419 C. proridens were used to determine age. Ages ranged from 0 to 10 with 88% of the fish being between 0 and 4 years. Females ranged in age between 0 and 7 years, while males ranged between 1 and 10 years. The von Bertalanffy growth model fitted to these data was L(t)=333.9[1-e-0.186(t+2.53)]. The relationship between otolith radius and fork length can be represented as OR=0.0034FL+0.0507 (R2=0.70, p<0.0001). Marginal increment analysis will be done to confirm annual deposition of an annulus. The fork length – weight relationship can be described as W=0.1496FL3.2891 for females, W=0.2227FL2.7898 for males, and transitionals as W=0.2048FL2.8934.

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Cypress saplings survive four weeks of complete submergence J.L. Whitbeck1, J.C. Roberts1 and T. Forman2, 1 University of New Orleans, New Orleans, LA, and 2 Coalition to Restore Coastal Louisiana, Baton Rouge, LA.

One and two year old cypress saplings, transplanted into a restoration site in the Bonnet Carré Spillway (BCS) ten days before it was opened in April 2008, survived four weeks of continuous complete submergence in diverted Mississippi River water (see Figures 1 & 2). Saplings retained their foliage during and after the flooding event. Three months after transplanting, survivorship of these cypress saplings did not differ from those of saplings transplanted into nearby sites in the LaBranche wetlands that were not exposed to sustained flooding or submergence. Considering all seed sources, survivorship at three months after transplanting ranged from 95 to 100 percent across the five field sites. Survivorship at the submerged Spillway site was similar among different sapling seed sources, different sapling root system volumes and different stages of foliage flushing at the time of submergence. Although we observed a lot of variation in relative height growth among seed sources and sites, cypress sapling height growth during the first three months after transplanting was comparable between the Spillway site and the LaBranche wetland sites. At the Spillway site, height growth was slower for bare root saplings than for saplings planted with intact roots and nursery soil. In our report we will include new data on cypress sapling survivorship and relative height growth at six months after transplanting. Little sediment was deposited in the Spillway site during the flood event, and flood waters were colder than ambient air temperatures. This evidence of cypress sapling tolerance of prolonged submergence during springtime Lower Mississippi River flooding suggests that cypress restoration projects may flourish in areas subject to natural or engineered delivery of cool fresh water, including overbank flooding or diversions.

Figure 1. BCS site prior to flooding, April, 2008 Figure 2. BCS site in flood, April 2008

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Comparative influence of chronic sea level rise vs. acute hurricane disturbance on coastal bottomland hardwood forest productivity J.L. Whitbeck. University of New Orleans, New Orleans, LA.

Global increase in temperature – global warming – contributes to both rising sea level and increased frequency of intense tropical storms. Coastal ecosystems within the ‘cyclone belt’ are subject to both of these environmental changes, and those of low gradient coastlines – such as the Mississippi River delta – are already experiencing shifts in these key state factors. Using data from a long-term productivity study in bottomland hardwood forest in southeastern Louisiana, I evaluate the impact of intense canopy disturbance from hurricanes on patterns of aboveground litterfall across a natural hydrologic gradient. I employ this hydrologic gradient as a proxy for rising sea level.

I conducted this work at three sites along a 500 m long transect spanning a 1 m elevation drop between the natural levee of a former distributary of the Mississippi River and a deep water swamp dominated by bald cypress. This transect runs adjacent to the north edge of a 5 ha permanent plot situated within a large tract of secondary growth bottomland hardwood forest that is protected as part of the Barataria Unit of the Jean Lafitte National Historical Park and Preserve. The forest is growing on continuous alluvial clay soils characterized as Sharkey series.

For four years prior to the windstorm disturbances of Hurricanes Cindy and Katrina in summer 2005, litterfall productivity peaked at the intermediate elevation site (Figure 1). At this position on the transect environmental stressors are moderate; it experiences neither the prolonged flooding of the lower elevation “swamp” site nor the occasional drought conditions of the higher elevation “ridge” site. Litterfall productivity diminished strongly in the year following these hurricane disturbances. While litterfall was similar among sites in 2006, during 2007 litterfall productivity recovered substantially at the “ridge” and “swamp” sites, but remained lower at the “intermediate” site. I assess the shift in litterfall following hurricane disturbance in the context of rapidly rising relative sea level, and I compare the relative impacts of rising sea level and increased frequency of intense tropical storms on coastal bottomland forest ecosystem processes.

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Environmental Impacts of the MRGO Closures at Bayou Loutre and Bayou Bienvenue Laura Lee Wilkinson1, Alison Sleath Grzegorzewski1 and Lee Walker2 1US Army Corps of Engineers Hurricane Protection Office, 7400 Leake Avenue, New Orleans, LA 70118 2Evans-Graves Engineers, 1 Galleria Blvd Suite 1520, Metairie, LA 70001

The Mississippi River-Gulf Outlet (MRGO) is approximately 76 miles long, located within the Pontchartrain Basin of the coastal Louisiana deltaic plain. The MRGO was a Federally-authorized 36-foot deep, 500-foot bottom width waterway to allow deep-draft access to New Orleans area port facilities via a shorter route than using the Mississippi River. It extends from the Inner Harbor Navigation Canal (IHNC) to the 38-foot depth contour of the Gulf of Mexico. Congress authorized MRGO channel construction in the River and Harbor Act of 1956. Construction of the channel began in 1958 and was completed in 1968. Construction of the MRGO converted nearly 3,400 acres of intermediate marsh, over10,300 acres of brackish marsh, over 4,200 acres of saline marsh and 1,500 acres of cypress and levee forest to open water or disposal area (USACE for Environmental Subcommittee of the EPA Technical Committee, 1999). The hydrologic connection that currently exists for Lake Pontchartrain through the IHNC, GIWW, MRGO has provided a conduit for more saline Gulf of Mexico water to be conveyed into the marshes around the golden triangle and into Lake Pontchartrain. Direct costs of construction, operation, and maintenance of the MRGO have been funded by the Federal government. These direct costs have totaled over $578 million since 1958. Average annual Operations and Maintenance (O&M) costs to dredge the MRGO deep-draft channel was $12.5 million.

In response to Congressional directive to develop a MRGO de-authorization plan, the U.S. Army Corps of Engineers (USACE) established a plan of action. In November 2007, USACE released The Integrated Final Report and Legislative Environmental Impact Statement (LEIS) for the Mississippi River Deep-Draft De-Authorization (MRGO-3D) Study (USACE 2007). The recommended plan called for the construction of a total closure structure across the MRGO near Bayou La Loutre. On June 5, 2008 the Chief’s Report on this LEIS was transferred to Congress, and this action deauthorized the channel and allows closure construction which is scheduled to start in January 2009. In August 2008, a second closure structure across the MRGO was proposed approximately 2,700 ft southeast of the existing Bayou Bienvenue flood control structure as part of the 100-year level of protection for the Greater New Orleans Hurricane and Storm Damage Risk Reduction System (GNOHSDRRS), formerly known as the Hurricane Protection System (HPS). This closure is part of the proposed storm surge barrier identified in Individual Environmental Report (IER) # 11 Tier 2 Borgne “Improved Protection on the Inner Harbor Navigation Canal, Orleans and St. Bernard Parishes, Louisiana” (USACE 2008a).

Recent hydrodynamic modeling studies were conducted in support of IER # 11 Tier 2 Borgne to analyze impacts of various structural alternatives. These modeling scenarios were developed and reviewed by USACE (ERDC, HPO, and MVN) and an interagency team made up of USFWS, National Marine Fisheries Service (NMFS), EPA, and LDNR, as well as experts from the University of New Orleans, Texas A&M, University of Florida, and Notre Dame, and international private industry firms.

A hydroperiod numerical modeling study was conducted to investigate the spatial and temporal extent of tidal inundation in the “golden triangle marsh” area at the confluence of the IHNC, Gulf Intracoastal Waterway (GIWW), and the MRGO (USACE 2008b). The modeling system for the study was established by fine-tuning existing models used for the hurricane storm surge analysis in Southern Louisiana for the Louisiana Coastal Protection and Restoration project, as well as the recent flood insurance rate map modernization study conducted by the Federal Emergency Management Agency (FEMA) (Westerink et al. 2007a; Westerink et al. 2007b). Both closures across the MRGO were represented in the modeling study. While the tidal phase is generally unchanged in the golden triangle marsh area, some areas of marsh experience several inches of additional inundation due to the MRGO closures. In addition, the frequency of marsh inundation is affected by the MRGO closures, with some marsh areas experiencing additional hours of inundation per day. Overall, the inundation impacts due to the MRGO closures are considered relatively small.

A three-dimensional velocity and salinity impact analysis was performed with TABS-MDS. Comparison of modeling scenarios illustrated that a closure structure across the MRGO at Bayou La Loutre had a significant effect on monthly average bottom salinity values not only within the MRGO, GIWW, and IHNC,

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but also within the Lake Borgne area. Salinity decreases up to 3-4 ppt were predicted for most areas due to the La Loutre closure. However, localized salinity decreases up to ~10ppt were predicted just north of the closure at Bayou La Loutre. Predicted salinity impacts were much less (on the order of 0.5 ppt or less) for the second closure across the MRGO just south of Bayou Bienvenue (USACE 2008c).

References USACE for the Environmental Subcommittee of the Technical Committee Convened by EPA in Response to St. Bernard Parish Council Resolution 12-98. 1999. Habitat Impacts of the construction of the MRGO. 83 p. U.S. Army Corps of Engineers (USACE). 2007. The Integrated Final Report and Legislative Environmental Impact Statement for the Mississippi River Deep-Draft De-Authorization (MRGO-3D) Study ---. 2008a. Individual Environmental Report #11 Improved Protection on The Inner Harbor Navigation Canal, Orleans and St. Bernard Parishes, Louisiana. IER #11 Tier 2 Borgne. ---. 2008b. Hydroperiod Modeling Study, Inner Harbor Navigation Canal Proposed Barrier Golden Triangle Marsh. ---. 2008c. Floodgate Analysis of the Mississippi River Gulf Outlet and Gulf Intracoastal Waterway. ERDC/CHL TR-08-X. Westerink, J.W., D. Resio, F.R. Clark, H. Roberts, J. Atkinson, J. Smith, C. Bender, J. Ratcliff, B. Blanton, and R. Jensen. 2007a. “Flood Insurance Study: Southeastern Parishes, Louisiana - Intermediate Submission 2.” U.S. Army Corps of Engineers. Westerink, J.J., J.C. Feyen, J.H. Atkinson, R.A. Luettich, C. Dawson, H.J. Roberts , M.D. Powell, J.P. Dunion , E. J. Kubatko, and H. Pourtaheri. 2007b. “A Basin to Channel Scale Unstructured Grid Hurricane Storm Surge Model Applied to Southern Louisiana,” Monthly Weather Review, In Press.

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BASICS OF THE BASIN NINTH BIENNIAL RESEARCH SYMPOSIUM · 2020. 6. 23. · Mark Schexnayder LSU...

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