Natural History of Idaho

Amphibians and Reptiles

Wildlife Ecology, University of Idaho

Fall 2008

Charles R. Peterson

Herpetology LaboratoryDepartment of Biological Sciences,

Idaho Museum of Natural History

Idaho State University

http://www.isu.edu/~petechar

Objectives:

• Know how to find information on amphibians and reptiles.

• Have an appreciation for the diversity and importance of

amphibians and reptiles.

• Be able to find and identify Idaho amphibians and reptiles.

• Know the basic natural history patterns of Idaho amphibians

and reptiles.

• Be aware of conservation problems and solutions.

Outline: Idaho Amphibians and Reptiles

• Readings – Pough – Chapters 10, 12, & 13

– Stuart et al. 2004.

– Gibbons et al. 2000

• Introduction– Sources of Information

– Types and Characteristics

– Importance

• Natural History

• Identification (lab)

• Conservation

Sources of Information

• Books and Leaflets

• Scientific Journals

• Web Sites

• Scientific Societies

• Conservation Groups

• Courses

Idaho Digital Atlas Website:

http://www.imnh.edu/digitalatlas/

Types and Numbers of Amphibians

Pough et al. 1999

Taxon World U.S. Idaho

Caecilians 165 0 0

Salamanders 415 ~200 5

Anurans 3750 ~100 10

Total 4330 ~300 15

6.9% 0.3%

Characteristics of Amphibians

• Thin smooth, moist skin

• Breathe via gills, skin, and/or lungs

• Gelatinous eggs

• Complex Life Cycle

• Ectothermic

Types of Reptiles

• Turtles

• Lizards

• Snakes

• Crocodilians

• Tuatara

Numbers of Reptile Species

Source: Behler and King, 1979

Pough et al. 1999

Taxon World U.S. Idaho

Turtles 260 48 1

Crocodilians 21 2 0

Tuatara 2 0 0

Lizards 3500 115 10

Snakes 2500 115 11

Total 6283 280 22

4.5% 0.4%

Characteristics of Reptiles

• Dry, scaly skin

• Breathe via lungs

• Amniotic eggs

• Direct development

• Ectothermic

Ectothermic

• Closely coupled to environment

• low energetic requirements

• low visibility

• high conversion efficiency

• high biomass

Importance of Amphibians and Reptiles

• Biodiversity

• Functional Roles in Ecosystems

• Bioindicators

• Economic Value

• Model Systems for Research

• Biomedical Applications

• Aesthetic Appreciation

Natural History

• Morphological Characteristics

• Physiological Characteristics

• Distribution

• Habitat

• Activity Patterns

• Movements

• Feeding

• Defense

• Reproduction and Life History

• Status and Conservation

Morphological Characteristics: Size

Idaho amphibians and reptiles are small to intermediate in size.

Physiological Characteristics: Thermal Biology

• Ectothermy

• Temperature tolerances

• Thermal Dependency

Physiological Characteristics:Freeze Tolerance

Physiological Characteristics:Water Relationships

Distribution:

• General Patterns

– Species Richness

– Latitude

– Elevation

– Complementarity

Species

Richness of

Idaho

Amphibians

Regional Endemics

Coeur d’Alene

Salamander

Rocky Mountain

Salamander

Idaho Giant

Salamander

Introduced Species

Roughskinned Newt

American Bullfrog

Complementarity of Mole Salamander Distributions

Tailed Frog(Ascaphidae)

Great Basin Spadefoot(Pelobatidae)

True Toad DistributionsComplementarity of Tree Frog

Distributions

True Frog Distributions Species

Richness

of Idaho

Reptiles

Widespread Reptile Distribution Patterns

Rubber Boa Racer Gopher Snake

Terrestrial Garter Snake Common Garter Snake Western Rattlesnake

Western Skink

?

Northern Reptile Distribution Patterns

Introductions in southern Idaho

Northern Alligator LizardPainted Turtle

Southern Reptile Distributions

Striped WhipsnakeLongnosed

Leopard LizardTiger Whiptail

Common Sagebrush Lizard

Western Fence Lizard

Common Side-blotched Lizard

Pigmy Short-horned Lizard

Desert Horned Lizard

Limited Reptile Distribution Patterns

Longnose Snake Ground Snake

Ringnecked Snake

Great Basin Collared Lizard

.

Night Snake Prairie Rattlesnake

Elevational

Distribution

Amphibian Habitat

• Breeding

– Pond (lentic)

– Stream (lotic)

– Terrestrial

• Foraging

• Overwintering

Breeding Sites Foraging Sites

Over-wintering Sites

Lentic Habitat Lotic Habitat

Terrestrial Habitat Reptile Habitat

• Cover types– shrublands

– grasslands

– forest

– riparian

– alpine

• Habitat elements– substrate

– slope

– aspect

Desertic Shrubland - southwestern Idaho Desertic Shrubland - southwestern Idaho

Shrubland - southeastern Idaho Riparian and Wetland Habitat:

Habitat: Overwintering

“Going Down” Mark Kelso

Activity Patterns and Movements

• Daily– diurnal

– nocturnal

– crepuscular

• Seasonal – overwintering

– breeding

– gestation

– foraging Breeding Sites Foraging Sites

Over-wintering Sites

0 .5 1 Kilometers

Spotted Frog Movements in the Bighorn Crags

Fishless Lakes

Movements

• Wide Range

– territorial species

– migrations

North

2 km

Visualizing rattlesnake movements and habitat use Natural History

• Morphological Characteristics

• Physiological Characteristics

• Distribution

• Habitat

• Activity Patterns

• Movements

• Feeding

• Defense

• Reproduction and Life History

• Status and Conservation

Feeding

• Diet

• Foraging mode

• Prey capture

• Energetic requirements

Feeding: Diet

• Salamanders

– larvae

• mostly carnivorous

• some cannibalism

– adults

• mostly opportunistic

carnivores

Feeding: Diet

Anurans

– larvaegenerally herbivoroussome scavengerssome carnivores

some cannibalism

– adults

mostly opportunistic carnivores

mostly invertebrates

some vertebrates

Feeding: Diets

• Painted Turtle:

omnivorous

• Lizards:

primarily carnivorous

• Snakes:

exclusively carnivorous

Feeding: Foraging Mode

• Sit and wait vs. Active foraging

Sagebrush Lizard Tiger Whiptail

Western Rattlesnake Striped Whipsnake

Feeding: Foraging Mode Correlates

Pough et

al. 1999.

Table 15-4

Feeding - Prey Capture

Examples

• Gape and Suck

• Grazing

• Tongue projection

Feeding - Prey Capture

Examples

• Grasping

• Constriction

• Envenomation

Feeding: Energetic Requirements

Rubber Boa (Charina bottae)

Defense

• Hiding/crypsis

• Evasion

Defense: Engagement Defense: Engagement

Natural History

• Morphological Characteristics

• Physiological Characteristics

• Distribution

• Habitat

• Activity Patterns

• Movements

• Feeding

• Defense

• Reproduction and Life History

• Status and Conservation

Reproduction and Life History

• Reproductive Modes

• Reproductive Schedules

• Mating Systems

• Gestation

• Sex Determination

• Parental Care

• Age to sexual maturity

• Longevity

Reproduction and Life History:

Longevity

Examples

– Boreal Chorus Frogs 2-3 years

– Western Toads > 20 years

– Side-blotched Lizards 2-3 years

– Rubber Boas > 30 years

– Painted Turtles > 50 years

Status and Conservation

• See species checklists

• Idaho Department of Fish and Game – Conservation Data Center:

http://fishandgame.idaho.gov/tech/CDC/heritage_ranks.cfm

www.isu.edu/~petechar

Questions?