THE EFFECT OF POOL GEOMORPHOLOGY ON FEEDING MORPHOLOGY OF ALPODINOTUS

GRUNNIENS AND LEPOMIS MACROCHIRUS IN THE OHIO RIVER, USA

Adam GerughtyCandidate For Masters of Environmental Studies

Dr. Tamara Sluss

Lotic Systems

• Characteristics:– Running water– Connected system– Open system•These characteristics make rivers difficult to study.

—Expensive—Hard to setup experiments—Time consuming—Each river around the world is different—Hard to create concepts for all rivers

Basic River Concepts• In attempt to describe rivers ecosystems many concepts have been

created.• River Continuum Concept (RCC)

– As the stream order increases the main source of production changes causing each stream order to have a different variety of organisms. (Vannote et al. 1980)

•Flood Pulse Concept (FPC)−Pulsing river discharge has a greater impact on food webs and

supports allochthonous materials from the floodplain and not just from production in the riparian zone (Junk et al. 1989)•Inshore Retention Concept (IRC)

–IRC explains how the biota and production levels change based on the river water retention, meaning the water velocity or discharge controls the biotic diversity and production levels. (Schiemer et al. 2001)

Introduction to the Ohio River

• Ohio River flow was created when Monongahela and Allegheny rivers converged in Pennsylvania

• Ohio River is about 1,579 river kilometers long and connects with the Mississippi River at Cairo, Illinois

• Ohio River drainage basin is about 517,998 square kilometers

(Ray 1974)

(Ray 1974)

Geological Formation of the Ohio

Ohio River Subdivision Valley Floodplain

Upper Ohio (alluviated valley)

High valley walls Wide Channel

Vast floodplain

Glaciated Valley Narrow Channel with steep banks

Narrow limited floodplain

Constricted Valley Deep valley wallsNarrow channel

Floodplain almost nonexistent

Alluviated Valley Extensive bottomlands Vast floodplain

(Ray 1974)

Navigational Dams of the Ohio• The Ohio River contains 20 navigational dams which have

channelized it and artificially control the flood stages (Ray, 1974).

• Maintain minimum water levels for barge traffic (US Army Corps of Engineers Pittsburgh District 2012)

• Water pools behind the dam, each pool has upstream riverine characteristic, high water velocity, and a downstream lacustrine like portion just above the dam (Wetzel 2001).

riverinelacustrineDam

(US Army Corps of Engineers)

Aplodinotus grunniens

• Main Characteristics– Habitat: Open warm waters with a muddy benthic

zone– Food: Young individuals feed primarily on

copepods and cladocerans, while adults feed on crayfish, fish, and mollusks

– Hunting behaviors: Rely on sight and touch to feed

(Priegel 1967)

Lepomis macrochirus

• Main Characteristics– Habitat: Prefer warm waters, can be found among

the littoral zone along lakes and rivers– Food: Young individuals feed on copepods and

cladocerans while adults feed on large insects or the occasional frog or fish

– Hunting behaviors: Rely on sight to find insects near the surface

(Snow et al. 1960)

Research Objectives

• Compare mouth morphology between navigational dam sites for Aplodinotus grunniens and Lepomis macrochirus

• Asses any similarities between sites• Conjecture what might be causing differences

if any

Methods: Specimen Collection

• Specimens for this project were obtained from Cincinnati Natural History Museum preserve ichthyology collection

• The specimens were preserved in a solution of 95% ethanol in a container had that had a specific ID number, information on location, date of the specimens was obtained, method of collection and a lot number which were recorded.

• Pictures were captured by using a Nikon D90 digital camera

• A. grunniens (n=155) & L. macrochirus (n=45)

(Adam Gerughty)

2 cm

2 cm

(Adam Gerughty)

Data Collection

• Each picture was then uploaded into imaging software, Spot Advance version 4.7 created by Diagnostic Inc

• The pictures were calibrated• Ten morphological measurements were

recorded

Maximum Standard Length

Fork Length

Maximum Total Length

(Adam Gerughty)

2 cm

Body DepthEye Diameter

Head Depth

Head Length

Snout Length

Jaw Length

(Adam Gerughty)

2 cm

Gape Width

(Adam Gerughty)

2 cm

Methods: Statistical Analysis• 20 different mouth morphology standardizations were

created• Principle Component Analyses (PCA) was used to

determine any differences between navigational sites using PC-ORD.

• Bonferroni-correct probabilities were used to determine the statistical significance in the mouth morphology standardization data (Systat 10.2).

• Tukey HSD Multiple comparison probabilities were preformed to asses the statistical significance difference between navigational pool sites. (Systat 10.2)

Results: Descriptive Stats

A. grunniens L. macrochirus 0.000

1.000

2.000

3.000

4.000

5.000

6.000

7.000

Mean Mass for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (g

)

Results: Descriptive Stats

A. grunniens L. macrochirus 0.000

1.000

2.000

3.000

4.000

5.000

6.000

Mean Maximum Total Length for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (c

m)

Results: Descriptive Stats

A. grunniens L. macrochirus 0.000

0.500

1.000

1.500

2.000

2.500

3.000

3.500

4.000

4.500

5.000

Mean Maximum Standard Length for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (c

m)

Results: Descriptive Stats

A. grunniens L. macrochirus 0.000

1.000

2.000

3.000

4.000

5.000

6.000

Mean Fork Length for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (c

m)

Results: Descriptive Stats

A. grunniens L. macrochirus 0.000

0.200

0.400

0.600

0.800

1.000

1.200

1.400

1.600

Mean Head Depth for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (c

m)

Results: Descriptive Stats

A. grunniens L. macrochirus 0.000

0.050

0.100

0.150

0.200

0.250

0.300

0.350

0.400

0.450

0.500

Mean Snout Length for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (c

m)

Results: Descriptive Stats

A. grunniens L. macrochirus 0.000

0.050

0.100

0.150

0.200

0.250

0.300

0.350

0.400

0.450

0.500

Mean Gape Width of the Mouth for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (c

m)

A. grunniens L. macrochirus 0.200

0.210

0.220

0.230

0.240

0.250

0.260

0.270

0.280

Mean Jaw Length for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (c

m)

Results: Descriptive Stats

A. grunniens L. macrochirus 0.000

0.050

0.100

0.150

0.200

0.250

0.300

0.350

0.400

0.450

0.500

Mean Eye Diameter for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (c

m)

Results: Descriptive Stats

A. grunniens L. macrochirus 0.000

0.200

0.400

0.600

0.800

1.000

1.200

1.400

1.600

1.800

2.000

Mean Depth of the Fish Body for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (c

m)

Results: Descriptive Stats

A. grunniens L. macrochirus 0.000

0.200

0.400

0.600

0.800

1.000

1.200

1.400

1.600

Mean Head Length for Aplodinotus grunniens and Lepomis macrochirus

Species Name

Mea

n (c

m)

Results: Descriptive Stats

Results: Lepomis macrochirus PCA

PCA Eigenvalue Percent of Variance

Cumulative Percent of Variance Eigenvalue

----- ----------------- --------------- ----------- ---------------

1 7.887 39.434 39.434 3.598

2 5.101 25.504 64.938 2.598

3 2.894 14.472 79.41 2.098

4 1.886 9.43 88.84 1.764

5 0.749 3.744 92.584 1.514

6 0.553 2.764 95.348 1.314

7 0.46 2.3 97.648 1.148

8 0.229 1.147 98.795 1.005

9 0.128 0.638 99.432 0.88

10 0.058 0.29 99.723 0.769

Results: Lepomis macrochirus PCAStandardization  

PCA 1 PCA 2 PCA 3 Jaw length to mass 0.421 0.2011 0.7745Jaw length to maximum standard length 0.94 0.2213 -0.095Jaw length to fork length 0.9487 0.2412 -0.11Jaw length to maximum total length 0.9484 0.246 -0.129Jaw length to body depth 0.9463 0.1883 0.1045Jaw length to head length 0.2188 0.1929 0.4038Jaw length to eye diameter 0.7323 0.2943 -0.503Jaw length to snout length 0.7522 -0.078 -0.405Jaw length to head depth 0.9025 0.1722 0.0726Jaw length to gape width of the mouth 0.9455 -0.309 -0.066Gape width of the mouth to mass 0.0811 0.2727 0.8659Gape width of the mouth to maximum standard length -0.181 0.9029 -0.073

Gape width of the mouth to fork length -0.184 0.9424 -0.129Gape width of the mouth to maximum total length -0.196 0.9438 -0.143Gape width of the mouth to body depth 0.0331 0.8274 0.3108Gape width of the mouth to head length 0.0467 0.2511 0.4133Gape width of the mouth to eye diameter -0.226 0.6621 -0.569Gape width of the mouth to snout length -0.481 0.4101 -0.453Gape width of the mouth to head depth 0.117 0.7033 0.2506Gape width of the mouth to jaw length -0.928 0.291 0.073

Results: Lepomis macrochirus PCA Analysis

-8 -6 -4 -2 0 2 4 6 8

-4

-3

-2

-1

0

1

2

3

4

Lepomis macrochirus Mouth Standardizations: PCA 1 vs. PCA 2

Pike Island poolWillow Island poolGreenup poolMarkland poolNewburgh poolUniontown pool

PCA 1 (dimensionless)

PCA

2 (d

imen

sion

less

) Alluviated valley

Glaciated valley

Alluviated valley

Results: Lepomis macrochirus PCA Analysis

-8 -6 -4 -2 0 2 4 6 8

-6

-4

-2

0

2

4

6

Lepomis macrochirus Mouth Standardizations: PCA 1 vs. PCA 3

Pike Island poolWillow Island poolGreenup poolMarkland poolNewburgh poolUniontown pool

PCA 1 (dimensional less)

PCA

3 (d

imen

siona

l les

s) Alluviated valley

Glaciated valley

Alluviated valley

Results: Aplodinotus grunniens PCA

PCA Eigenvalue Percent of VarianceCumulative Percent of Variance Eigenvalue

1 7.72 38.602 38.602 3.598

2 4.629 23.144 61.746 2.598

3 2.003 10.014 71.76 2.098

4 1.855 9.275 81.035 1.764

5 1.783 8.917 89.952 1.514

6 1.065 5.325 95.277 1.314

7 0.429 2.147 97.424 1.148

8 0.291 1.455 98.88 1.005

9 0.076 0.379 99.258 0.88

10 0.042 0.212 99.471 0.769

Results: Aplodinotus grunniens PCA AnalysisStandardizations Eigenvector

1 2 3

Jaw length to mass 0.5975 -0.1438 -0.3402

Jaw length to maximum standard length 0.9277 -0.3258 0.0133

Jaw length to fork length 0.93 -0.3199 0.0083

Jaw length to maximum total length 0.9282 -0.3227 0.0434

Jaw length to body depth 0.208 -0.2252 0.5849

Jaw length to head length 0.872 -0.2841 0.1284

Jaw length to eye diameter 0.2274 -0.4245 -0.5948

Jaw length to snout length 0.5732 -0.0835 0.3611

Jaw length to head depth 0.8395 -0.3574 -0.0434

Jaw length to gape width of the mouth 0.9725 0.1508 -0.0363

Gape width of the mouth to mass 0.2546 -0.2056 -0.3511Gape width of the mouth to maximum standard length -0.169 -0.908 0.0568

Gape width of the mouth to fork length -0.1892 -0.9057 0.0417

Gape width of the mouth to maximum total length -0.2398 -0.8935 0.1132

Gape width of the mouth to body depth 0.0576 -0.2594 0.586

Gape width of the mouth to head length -0.47 -0.7086 0.1584

Gape width of the mouth to eye diameter -0.2172 -0.3898 -0.6074

Gape width of the mouth to snout length -0.6066 -0.2552 0.35

Gape width of the mouth to head depth -0.4669 -0.7143 -0.1741

Gape width of the mouth to jaw length -0.9474 -0.2107 -0.0877

Results: Aplodinotus grunniens PCA Analysis

-8 -6 -4 -2 0 2 4 6 8 10

-10

-8

-6

-4

-2

0

2

4

6

Aplodinotus grunniens Mouth Standardizations: PCA 1 vs. PCA 2

Pike Island poolWillow Island poolBelleview poolR.C. Byrd poolGreenup poolMarkland poolMcApline poolCannelton poolNewburgh poolUniontown pool

PCA 1 (dimensionless)

PCA

2 ( d

imen

sion

less

)

Alluviated valley

Glaciated valley

Alluviated valley

Constricted valley

Results: Aplodinotus grunniens PCA Analysis

-8 -6 -4 -2 0 2 4 6 8 10

-12

-10

-8

-6

-4

-2

0

2

4

6

8

Aplodinotus grunniens Mouth Standardizations: PCA 1 vs. PCA 3

Pike Island poolWilliow Island poolBelleview poolR.C. Byrd poolGreenup poolMarkland poolMcApline poolCannelton poolNewburgh poolUniontown pool

PCA 1 (dimensionless)

PCA

3 (d

imen

sionl

ess)

Alluviated valley

Glaciated valley

Alluviated valley

Constricted valley

Uniontown pool

Newburgh pool

Cannelton pool

McApline pool

Markland pool

Greenup pool R.C. Byrd pool Belleview pool

Williow Island pool

Pike Island pool

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

0.090

Navigation Pool Mean for Jaw Length to Maximum Standard Length

Navigational Pool Name

Mea

n (d

imen

sionl

ess)

Uniontown pool

Newburgh pool

Cannelton pool

McApline pool

Markland pool

Greenup pool R.C. Byrd pool Belleview pool

Willow Island pool

Pike Island pool

0

0.005

0.01

0.015

0.02

0.025

0.03

Navigation Pool Standard Deviation for Jaw Length to Maximum Standard Length

Navigational Pool Name

Stan

dard

Dev

iatio

n (d

imen

sionl

ess)

Uniontown pool

Newburgh pool

Cannelton pool

McApline pool Markland pool Greenup pool R.C. Byrd pool Belleview pool Williow Island pool

Pike Island pool

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

Navigation Pool Mean for Jaw Length to Fork Length

Navigational Pool Name

Mea

n (d

imen

sionl

ess)

Uniontown pool

Newburgh pool

Cannelton pool

McApline pool

Markland pool

Greenup pool R.C. Byrd pool

Belleview pool

Willow Island pool

Pike Island pool

0

0.005

0.01

0.015

0.02

0.025

Navigation Pool Standard Deviation for Jaw Length to Fork Length

Navigational Pool Name

Stan

dard

Dev

iatio

n (d

imen

sionl

ess)

Uniontown pool

Newburgh

pool

Cannelt

on pool

McAplin

e pool

Marklan

d pool

Greenup pool

R.C. Byrd

pool

Bellevi

ew pool

Williow Isl

and pool

Pike Isl

and pool

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

Navigation Pool Mean for Jaw Length to Maximum Total Length

Navigational Pool Name

Mea

n (d

imen

sionl

ess)

Uniontown pool

Newburgh

pool

Cannelt

on pool

McAplin

e pool

Marklan

d pool

Greenup pool

R.C. Byrd

pool

Bellevi

ew pool

Willow Isl

and pool

Pike Isl

and pool

0

0.005

0.01

0.015

0.02

0.025

Navigation Pool Standard Deviation for Jaw Length to Maximum Total Length

Navigational Pool Name

Stan

dard

Dev

iatio

n (d

imen

sionl

ess)

Uniontown pool

Newburgh

pool

Cannelt

on pool

McAplin

e pool

Marklan

d pool

Greenup pool

R.C. Byrd

pool

Bellevi

ew pool

Williow Isl

and pool

Pike Isl

and pool

0.000

0.050

0.100

0.150

0.200

0.250

Navigation Pool Mean for Jaw Length to Head Length

Navigational Pool Name

Mea

n (d

imen

sionl

ess)

Uniontown pool

Newburgh pool

Cannelton pool

McApline pool Markland pool

Greenup pool R.C. Byrd pool Belleview pool Willow Island pool

Pike Island pool

0

0.01

0.02

0.03

0.04

0.05

0.06

Navigation Pool Standard Deviation for Jaw Length to Head Length

Navigational Pool Name

Stan

dard

Dev

iatio

n (d

imen

sionl

ess)

Uniontown pool

Newburgh

pool

Cannelt

on pool

McAplin

e pool

Marklan

d pool

Greenup pool

R.C. Byrd

pool

Bellevi

ew pool

Williow Isl

and pool

Pike Isl

and pool

0.0000.0500.1000.1500.2000.2500.3000.350

Navigation Pool Mean for Jaw Length to Head Depth

Navigational Pool Name

Mea

n (d

imen

sionl

ess)

Uniontown pool

Newburgh pool

Cannelton pool

McApline pool Markland pool

Greenup pool R.C. Byrd pool Belleview pool Willow Island pool

Pike Island pool

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

Navigation Pool Standard Deviation for Jaw Length to Head Depth

Navigational Pool Name

Stan

dard

Dev

iatio

n (d

imen

sionl

ess)

Uniontown pool

Newburgh

pool

Cannelt

on pool

McAplin

e pool

Marklan

d pool

Greenup pool

R.C. Byrd

pool

Bellevi

ew pool

Williow Isl

and pool

Pike Isl

and pool

0.0000.1000.2000.3000.4000.5000.6000.7000.8000.900

Navigation Pool Mean for Jaw Length to Gape Width

Navigational Pool Name

Mea

n (d

imen

sionl

ess)

Uniontown pool

Newburgh pool

Cannelton pool

McApline pool

Markland pool

Greenup pool R.C. Byrd pool

Belleview pool

Willow Island pool

Pike Island pool

0

0.05

0.1

0.15

0.2

0.25

0.3

Navigation Pool Standard Deviation for Jaw Length to Gape Width of the Mouth

Navigational Pool Name

Stan

dard

Dev

iatio

n (d

imen

sionl

ess)

Discussion: Lepomis macrochirus• Lepomis macrochirus showed no morphological

differences between navigational dam sites. • The sample size was low, additional Lepomis macrochirus

would need to be measured until an accurate conclusion could be formulated.

• One possible reason why there are no morphological differences is because L. macrochirus relies on the littoral zone of the river for surface insects. (Snow et al. 1960)

• The littoral zone might have similar characteristics between the alluviated valley and glaciated valley.

• Another possibility is that the L. macrochirus is not competing with other species.

Discussion: Lepomis macrochirus• When Lepomis cyanellus and Lepomis macrochirus

cohabitate, L. cyanellus exhibits a higher survivorship, growth rate, and greater amount of food contain in the stomach compare to L. macrochirus (Werner and Hall 1977).

• Competition in the littoral zone could be low in both valleys resulting in similar morphology between sites.

• If competition was high in either one of the sites, there would be a difference in morphology.

• If interspecies competition was high in both sites, one would expect there be similar morphology.

Discussion: Aplodinotus grunniens jaw length

• Results have shown that there is measurable difference in the A. grunniens population.

• Individuals habiting the glaciated valley on average are probably eating smaller prey compared to individuals habiting the alluvial valleys, where the jaw length standardization mean is greater indicating that these individuals are eating larger prey.

• Individuals in the McApline navigational pool are probably feeding on cladocerans, copepods, small fish and small mollusks, while individuals in the alluvial valleys are feeding on bigger fish, mollusks, and crayfish (Wallus and Simon 2006).

• This would also indicate the glaciated valley and the alluvial valley have different size prey.

Discussion: Habitat Differences

• Alluvial valleys and glaciated valleys have very different characteristics

• A. grunniens existing in the alluvial valley are relying on the annual flooding cycle to utilize an area that has an abundant source of food and nutrients (Junk et. al 1989).

• Rely on insects and even plant matter for their diet. • Insects seem to be a good source of nutrients during

development (Daiber 1952). • The floodplain would be rich source of terrestrial

insects during flood season.

Discussion: Habitat Differences• Individuals in Uniontown navigational pool, R.C Byrd navigational pool,

and Newburgh navigational pool on average have larger jaw lengths.• They are developing correctly coupled with large terrestrial insects. • A. grunniens living McApline Pool are not receiving enough insects to

develop correctly or since the floodplain is constricted they are limited to eating smaller insects.

• RCC was not considered as an alternative to the FPC because the stream order was the same throughout the river.

• In previous studies where stable isotopes were examined, the flood pulse had little influence over dissolved organic matter in the river and most nutrients came from production in the river.

• The flood plain and backwaters were an important factor for fish, especially juveniles, to use as a safe refuge and an alternate food source (Thorp et al. 1998).

Discussion: Competition effects• There is more diversity in the jaw lengths in the alluviated

valleys than in the glaciated valley due to competition.• Competition has increased in the glaciated due to the

constricted flood plain.• The water velocities in the limited floodplain are not low

enough and food is being washed downstream.• There would also be limited space.• Competition in the alluviated valleys would be minimal.• The floodplain water velocities are low allowing for more

diverse array of food and space.• The food chain lengths would be longer allowing for more

selection of prey and species could feed on traditional niches (Roach et. al, 2009; Werner and Hall, 1976)

Discussion: Affect of Water Velocity• There have been experiments that showed changes in water

velocity have an effect on biota.• Mesocosms were used to examine the effect of water velocity

on zooplankton community density and population growth. • Rotifer populations would grew faster in high turbulence tanks,

while microcrustaceans faired better in lower turbulence tanks.

• This could indicate where certain zooplankton would likely be found along the Ohio River, further away from a dam one would most likely find rotifers, while microcrustaceans would occur in water near the dam (Sluss et al. 2008).

Conclusion: Future Studies• Stable isotopes and gut content analysis would help to

better understand what A. grunniens and L. macrochirus feed upon.

• An increase in sample size, studied sites, and species would help to statistically verify differences between sites.

• Genetic studies could also be conducted to assist in the verification of differences between studied sites.

• Separating individuals to the correct age classes would also help confirmed differences between navigational pool sites.

• The findings from this study and future studies along the Ohio River could be adapted to all large rivers

Acknowledgements• This study of not have been possible without the contributions of Dr.

Herman Mays and the Cincinnati Museum of Natural History loan of their ichthyology collection. I would also like to thank Thomas Moore College for allowing me to have access to their ichthyology collection. Special thanks to Dr. Tara Trammell of the University of Louisville for helping with data analysis through PC-ORD. I am grateful to have Dr. Tamara Sluss as my advisor for her constant support and guidance throughout this whole study. This study was supported by Dr. Kazi Javed, department head of the Master's in Environmental Studies program and Kentucky State University. This study was supported by Kentucky Water Resource Research Institute grant. I would like to thank Charles Weibel and Kentucky State University Aquaculture and Aquatic Sciences for providing matches from the grant.

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