Erika Nowak & Trevor B. Persons

USGS Southwest Biological Science Center Colorado Plateau Field Station

Inventory of Reptiles and Amphibians at

Death Valley NPManzanar NHS

Mojave NP

The Crew

Laura Cunninghamand Erika

Trevor Persons

Scott HillardShawn KnoxAJ MonatestiBob ParkerJason PilarskiJustin SchoferEric Zepnewski

Kevin EmmerichBryan HamiltonKris Heister/I&M Network David MorafkaDana York & all NPS staff CPFS administrative staff

Thanks to:

2. Maximize the probability of detecting new species in certain areas (fill in holes in park species lists)

Potential Inventory ObjectivesPotential Inventory Objectives

1. Provide a basis for statistical inference about species richness (provide rigor and repeatability)

-OR-

2. Maximize the probability of detecting new species in certain areasTargeted sampling

(DEVA, MOJA)

Potential Inventory ObjectivesPotential Inventory Objectives

1. Provide a basis for statistical inference about species richness

Stratified grid-constrained random sampling (MANZ)

-AND-

OUR OBJECTIVES

• Inventory and document the occurrence of reptile and amphibian species – Within identified priority sampling locations (DEVA and

MOJA)– Within all of MANZ– Provide one voucher specimen for each species if not

previously collected

• Estimate inventory completeness at each park (Master List)

• Enter species data into NPSpecies and provide other deliverables

http://sbsc.wr.usgs.gov/products/ofr

METHODS• Time-recorded visual encounter surveys (VES, NVES)

• Road driving (ROAD)

• Random encounters (RE)

• One hour - one hectare time-area constrained VES (TACS; MANZ)

• 100 m-long lizard line transects (LL; MANZ)

• Pitfall traps (PF; DEVA, MANZ)

• Data mining (museum searches, literature review, contact area experts)

– estimate inventory completeness

Owlshead PSA

Owlshead PSA

Greenwater PSA

DEVAPriority Sampling Areas (6)

2002-2004

DEVA: NOTABLE SPECIES

LIZARDS (16 species)• *Southern Alligator Lizard (1)

(Elgaria multicarinata)– Scotty’s Castle

• Mojave Fringe-toed Lizard (Uma scoparia)– state species of concern– Ibex Dunes

SNAKES (16 species)• *Ring-necked Snake (1)

(Diadophis punctatus)– near Scotty’s Castle

• Rosy Boa (Charina trivirgata)– rare, collected by poachers

– Darwin Falls

* = new park record

L. Cunningham

DEVA: NOTABLE SPECIES

DESERT TORTOISE(Gopherus agassizii)• Federally threated

– Greenwater range

AMPHIBIANS (4 species)

• Bullfrog (Rana catesbeiana)

– Saline Valley and Furnace Creek golf course

• Odd-looking Western toads (Bufo boreas) hybrids??

– Darwin Falls

• No salamanders documented (Batrachoseps seen outside park in Waucoba Canyon)

B. Parker

MANZ: COMPARISON OF METHODS2002-2003

# Species

TACS LL VES/

NVES

PF ROAD RE

Total

(per

pers-hr)

7

(0.36)

6

(0.11)

6

(0.09)

4

(245

t-days)

7

(0.09)

5

Lizards 5 4 6 4 5 5

Snakes 2 2 0 0 2 0

** NO ONE METHOD CAUGHT ALL SPECIES

MANZ: NOTABLE SPECIES

LIZARDS (7 species)• Southern Alligator Lizard

(Elgaria multicarinata)– apparently rare

SNAKES (3 species)Nothing unusual:• Gophersnake (Pituophis

catenifer)• Glossy Snake (Arizona elegans)• Coachwhip (Masticophis

flagellum)

AMPHIBIANS• NONE!!!!!

T. Persons

MOJA PRIORITY SAMPLING AREAS (4) 2004-2005

• Clark Range

• Piute Range• Piute Creek

• Cornfield Spring(Providence Mtns)

MOJA: NOTABLE SPECIES

LIZARDS (15 species)• Mojave Fringe-toed Lizard (Uma scoparia)

– Kelso Dunes• Did not find Gila Monster

(Heloderma suspectum) – seen in 2005 by tourist bet.

Clark and Kingston ranges

SNAKES (14 species)• Nothing unusual except high

road mortality

DESERT TORTOISE• federally threatened

– Not uncommon

AMPHIBIANS (1 species found)• Red-spotted Toad (Bufo punctatus)

– deformities in Piute Creek (post-fire)

• Did not find Pacific Treefrog (Hyla regilla)– introduced at ZZYZX

T. Persons

OVERALL RESULTS

OVERALL RESULTS: % INVENTORY COMPLETENESS

DEVA MANZ MOJA

Overall 92 50 95-100

Amphibians 73 0 67-100

Reptiles 95 54 97-100

DISCUSSION: TIMING ISSUES

• 2002-2004: Impact of drought on survey results– Likely decrease in numbers of individuals detected and

esp. on detected amphibian species richness

– Possible longer-term effects on age class structure

• 2005: WET!– Limited surveys done at MOJA

• Importance of longer-term studies– Done by park-based researchers

• Detectability near zero for some: – Secretive snakes– Rain-breeding amphibians

• Patchy spatial / temporal distribution– Does not support detection at randomly-generated plots

• Over half of rare species added by random encounters outside

standard methods

–

DISCUSSION: RARE SPECIES

J. Pilarski

DISCUSSION: SAMPLING ISSUES

• VES surveys most efficient for limited $$ inventories

• TACS and lizard line transects have limited utility for species inventory– TACS could be useful for monitoring if properly

stratified

• Pitfalls useful if long monitoring periods (or inventory if $$$$)– Will occasionally detect rare or

secretive species– **MUST BE CHECKED

FREQUENTLY**

DISCUSSION: HERP ISSUES

• Monitor/control non-native or introduced species – Bullfrogs (eat everything)– Fish/crayfish (eat amphibian eggs/larvae)

• Monitor amphibians at springs– Toad deformities at MOJA Piute Creek– Salamanders in DEVA Panamints??

• Throw money at surveys in wet years

• More general surveys at MANZ• Road mortality of snakes at MOJA

B. Parker

•There are several “populations” of herp species that differ primarily by detectability relative to method used

• Use a variety of methods for documentation• Random points are inefficient for inventories:

• largely document common, already listed species • Time, luck, cameras needed to detect rare species

•Herp inventories uncompleted in Mojave and other Network Parks

• Relative abundance estimable only for common species• Droughts necessitate longer

inventory periods• Park-funded best

CONCLUSIONS I: Implications for Future Herpetofauna Inventories

T. Persons

• Statistical inference or specific sample designs should not become ends in themselves

• Don’t confuse inventory and monitoring methods/objectives

• Documentation (of new species or locations) is simple!• Easily done by park-based NPS staff or tourists

• Need camera, GPS, date http://sbsc.wr.usgs.gov/products/ofr

CONCLUSIONS II: Implications for Future Herpetofauna Inventories

J. Pilarski

DEVA: EFFORT BY METHOD

VES

NVES

ROAD

PF

RE

TOTALS

Survey Hours

693.7

30.1

225.1

N/A

N/A

948.9

Person-hours

939.8

31.7

306.3

N/A

N/A

1,277.8

Kilometers Driven

N/A

N/A

8,413

N/A

N/A

8,413

Trap Days N/A

N/A

N/A

4,850

N/A

4,850

PFs at Hummingbird Springs, Mahogany Flats (also Cunningham and Emmerich traps at Scotty’s Castle and Last Chance Range)

MOJA: EFFORT BY METHOD

VES

NVES

ROAD

RE

TOTALS

# Surveys 92

8

40

123

263

Person-hours

192.2

4.3

115.7

N/A

312.1

Kilometers Driven

N/A

N/A

3487

N/A

3487

MANZ Random Plots*

(*TACS & LL)

2002-3003

DEVA Potential Reptile Species List Review

• long-tailed brush lizard• tree lizard• northern alligator lizard• southern alligator lizard• gila monster• ringneck snake • Mojave rattlesnake• western rattlesnake • western diamondback

rattlesnake • rubber boa• western terrestrial garter

snake

• previously seen in Greenwater Valley• not likely present – out of range• low probability of presence in N. mtns• we documented at Scotty’s Castle • not likely present- out of range• we documented at Scotty’s Castle• high probability of presence in S. • high probability of presence in N. mtns• not likely present- out of range

• not likely present- out of range• low probability of presence

DEVA Other Potential Species

• western skink• Mediterranean or house

gecko • CA mountain kingsnake• slender salamanders

(Batrachoseps)• ensatina (Ensatina

escholtzii) or web-toed salamander (Hydromantes)

• northern leopard frog

• Great Basin spadefoot • black toad

• specimen misidentified- not likely• unconfirmed reports at Scotty’s Castle-

unlikely• possibly present in moist habitats• slight probability of presence in canyons

of Panamint Mountains• previously recorded on Telescope Peak,

low probability of finding it

• likely present historically, low probability of presence in wetlands

• low-fair probability of presence• introduced in the Saline Valley Marsh

MANZ Potential Species List- Amphibians

• Slender Salamander (Batrachoseps sp.)  

• Owens Valley web-toed salamander (Hydromantes sp.)  

• Great Basin Spadefoot (Spea intermontana)

• Boreal (Western) Toad (Bufo boreas) 

• Pacific Treefrog (Hyla regilla)  

 

• low probability of presence along Bairs Creek

• not likely present – out of elevational range

• good probability of presence

• fair probability of presence

• low probability of presence along creek

MANZ Potential Species List- Lizards

• Western Banded Gecko (Coleonyx variegatus)  

• Desert Night Lizard (Xantusia vigilis)  

• Great Basin Collared Lizard (Crotaphytus bicinctores)  

• Western Fence Lizard (Sceloporus occidentalis) 

• Sagebrush Lizard (Sceloporus graciosus)  

• Western Skink (Eumeces skiltonianus)  

• high probability of presence

• good probability of presence

• low probability of presence

• low probability of presence

• low probability of presence

• fair probability of presence

MANZ Potential Species List - Snakes

•  Ringneck Snake (Diadophis punctatus) 

• Common Kingsnake (Lampropeltis getulus)

• Longnose Snake (Rhinocheilus lecontei)

• Western Patchnose Snake (Salvadora hexalepis)

• Ground Snake (Sonora semiannulata)  

• low probability of presence along Bairs Creek

• high probability of presence

• high probability of presence

• high probability of presence

• high probability of presence

Manz Potential Species List – More Snakes

• Western Terrestrial Garter Snake (Thamnophis elegans)

• Western Aquatic Garter Snake (Thamnophis couchii)

• Night Snake (Hypsiglena torquata) 

• Southwestern Black-headed Snake (Tantilla hobartsmithi)  

• Sidewinder (Crotalus cerastes)  

• Speckled Rattlesnake (Crotalus mitchelli)

• low probability of presence along Bairs Creek

• not likely present- unsuitable habitat

• high probability of presence

• good probability of presence

• high probability of presence

• high probability of presence