natural history of idaho objectives: amphibians and reptiles€¦ · •be able to find and...
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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?