Grand Canyon National Park National Park Service · Grand Canyon National Park U.S. Department of...

Grand Canyon National Park U.S. Department of the InteriorNational Park Service

Endangered Sentry Milk-Vetch Habitat Model

Mark Nebel, Lori Makarick, Jan Busco, Shahed Dowlatshahi Grand Canyon National Park June 16, 2014


Astragalus cremnophylax var. cremnophylax

Sentry Milk-Vetch South Rim of Grand Canyon


1903: First discovered at Grand Canyon 1980: Listed as candidate threatened species (1 known population) 1988: Half of population showed serious damage from trampling 1990: Federally listed as an endangered plant (150 known individuals) 1994-Present: New populations discovered (currently 4, ~4000 plants) 2006: USFWS Recovery Plan 2013: GIS Habitat Modeling 2014: First new population established

HISTORY


• Member of the Pea Family (Fabaceae)

• Endemic to Grand Canyon South Rim

• Endangered by Habitat Loss, Climate Change, Drought, Trampling

• Recovery Plan (2006) Objectives

•Down-list (Minimum 4 Populations of 1000 plants each)

•De-list (Minimum 8 Populations of 1000 plants each)

•Stable or Increasing over a 30-year period

• Partners: NPS, USFWS, The Arboretum at Flagstaff, Northern Arizona University, USGS, Desert Botanical Garden

• Use GIS Modeling capabilities to identify the most-suitable sites for Reintroduction Site Selection decision support


Sentry Milk-Vetch and Related Species


Model Variable: GeologyExclusively on Kaibab Limestone – White Limestone (Fossil Mountain

Member) “Spits” – Grows in Cracks on Outcrops, along

Edges, and on Graveled Slopes in Shallow Soil

– Possible relationship to Geologic Structures or Breccia Pipes?


Kaibab Limestone


South Rim Sentry Milk-Vetch Populations And Kaibab Limestone Geology


Geologic Unit Rank

Kaibab Limestone, undifferentiated 5

Kaibab Limestone, Fossil Mountain member 5

Kaibab Limestone, Harrisburg member 4

Model Variable: Geology


Model Variable: SlopeProximity to Canyon Rim – No more than 10 meters from “Rim” – How to define/represent “Rim”?

GIS “RimLine” Insufficient Proxy Slope

– All known populations fall within one 10-meter pixel of Slope >29 Degrees


Degrees Slope Rank

>29 5

10-29 3

0-10 1

Model Variable: Slope


Model Variable: VegetationProximity to Pinyon-Juniper Vegetation – “…just outside of Pinyon-Juniper

Vegetation Types…” Pinyon-Juniper, Sagebrush, Deciduous Shrub, and Conifer SMV Intersects All known SMV populations are within 16 meters of specific P-J Associations

Companion Species are important Open Areas without tall plant growth or dense grasses


Pinion-Juniper Vegetation Types


Companion Species •Lavender Leaf Sundrop

•Rockmat

•Wild Buckwheat

•Mountain Phlox

•Eastwoods’ Sandwort

•Fernbush

•Mock Penny Royal


Vegetation Association Rank

Intersected Types w/Key Companions 5

P-J Types +/- Key Companions 3-5

Other Veg Types +/- Key Companions 0-4

Model Variable: Vegetation Type


Model Variable: Distance to Pinyon-Juniper Associations w/Key Companion Species

Distance (Meters) Rank

0-16 5

16-30 4

30-60 3

60-200 2


Model Variable 5: SoilCrumbly Limestone-Gravel Soils Loose, Shallow, Inorganic Soils


Model Variable: Soil

Soil Type Rank

Lithic Ustic Torriorthents-Udic Haplustolls-Rock outcrop complex 5

Yumtheska-Rock outcrop complex 5

Skos family-Sandia-Rock outcrop complex 5

Meriwhitica-Rock outcrop complex 3

Other Soil Types 1


Model Variable: Aspect

Degrees Rank

0-25 4

25-56 5

56-90 4

90-186 4

186-270 2

270-360 4


Model Variable: ElevationKnown population range 2117-2250m

Meters Rank

<2100 1

2105-2115 3

2115-2250 5

2250-2260 3

>2260 1


Variable Weight (100%) Value Classes Ranks (1-5)

Geology 14% GeologicUnitKaibab Limestone, undifferentiated (Pk) 5

Kaibab Limestone, Fossil Mountain member (Pkf) 5Kaibab Limestone, Harrisburg member (Pkh) 4

Slope 14% Degrees0-10 110-29 3>29 5

Vegetation 16% AssociationSouth Rim Intersects PiEd-JuOs-ArSp 5

PiEd-JuOs-CeSp-QuSp 5ArBi-BoGr 5

QuGa 5AmUt 5

North Rim Intersects AbCo-PsMe-CaSp 5PiEd-JuOs-PuSt 5

PiPo-PoFe 5RoNe 5

Other PJ, w/companions See SMV_VegWorksheet

Model Variable Worksheet


Distance to PJCON 14% Meters0-16 516-30 430-60 3

60-200 2

Soil 14% Soil Type (MUNAME)Lithic Ustic Torriorthents-Udic Haplustolls-Rock outcrop complex, Kaibab, T 5

Yumtheska-Rock outcrop complex, 0 to 2 percent slopes 5Skos family-Sandia-Rock outcrop complex, 15 to 55 percent slopes 5

Meriwhitica-Rock outcrop complex, 35 to 70 percent slopes 3Other Soil Types 1

Elevation 14% Meters<2100 1

2105-2115 32115-2250 52250-2260 3

>2260 1

Aspect 14% Degrees0-25 425-56 556-90 4

90-186 4

Model Variable Worksheet, cont.


Model Builder


Model Run 1


Model OutcomesIterative; Change Weights and Ranks; Test Model Sensitive to Geology, Elevation, and Aspect – Significantly expand or shrink extent of

predicted Suitable Habitat Areas that consistently model as Highly Suitable over a wide range of model iterations increase confidence Field Validation is Critical New population (139 plants) discovered in predicted Highly Suitable Habitat Five Sites Selected for Initial Reintroduction, beginning in 2014


Relationship of Model Output to Known Sentry Milk-Vetch Populations


Model Run 1

Model Run 2

Changes in Model Weights to slightly emphasize Geology (Run 2) extends predicted Highly Suitable Habitat several kilometers away from the canyon rim and up to 50 kilometers northwest along the rim

Sensitivity Analysis


Model Run 1 Model Run 2

Model Run 3 Model Run 4


Newly Discovered Population


Other ConsiderationsLandforms, esp. Limestone “Spits” – Topographic Position Index Access – Low Visitor Use – Watering, Monitoring Expansion Potential Field Validation, Previous Surveys, and Partner Recommendations


Selected Reintroduction Sites


Greenhouse


Thank You!

Other Modeling Efforts •Northern Leopard Frog •Bighorn Sheep •And?…

Grand Canyon National Park National Park Service · Grand Canyon National Park U.S. Department of...

Documents

Transcript of Grand Canyon National Park National Park Service · Grand Canyon National Park U.S. Department of...