Amphibians and Reptiles: An Introduction to Herpetofauna

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Amphibians and Reptiles An Introduction to
Herpetofauna
Edited for Virginia by Mike Clifford, Virginia
Herpetological Society
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Amphibians and Reptiles

• Ectothermic
• Regulate temperature from outside sources
• Water temperature
• Basking

Yellow-bellied Slider
Northern Watersnake
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Amphibians and Reptiles

• Cryptic
• Very abundant but their presence is largely
  unknown

Northern Copperhead
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Amphibians and Reptiles

• Important to the ecosystem
• An important prey item for
• Raccoons, opossums, birds
• An important predator of
• Mice, rats, insects

Ringneck Snake
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Amphibians

• 78 Species in Virginia (51 salamanders
  27 frogs toads)
• SE U.S. - greatest salamander diversity in the
  world!
• Huge Biomass
• Biomass Total weight of all amphibians in an
  area
• One isolated wetland produced 3 tons of
  amphibians

Spotted Salamander
Three-lined Salamander
Southern Leopard Frog
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Amphibian Characteristics

• Permeable skin
• Permeable allows the transfer of oxygen and
  carbon dioxide to allow respiration
• Can allow the uptake of chemicals in the
  environment
• Good olfaction
• Olfaction Sense of smell
• Prey upon
• Insects, other amphibians, anything small enough
  to fit into their mouths, even mice

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Frogs

• Tadpoles when they are born
• Lose their tails as adults
• Two main types
• True Frogs
• Tree Frogs
• Toe-pads

Upland Chrous Frog
Pickerel Frog
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Toads

• Similar to frogs
• Tail-less as adults
• Warty skin
• Have large glands behind each eye that secretes
  toxin

American Toad
Fowlers Toad
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Salamanders

• Plethodontids Dont have lungs and must breathe
  entirely through their skin
• Ambystomatids Have lungs, but can also breathe
  through their skin
• Salamanders can lay eggs in
• Streams
• Wetlands
• Soil

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Caecilians

• Live in the tropics
• Leg-less and blind
• Look very similar to a worm

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Amphibian Life Cycle
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Amphibian Defense Mechanisms
American Toad

• Poison in skin
• Toads and Newts
• Producing large numbers of offspring
• Producing noisy squawks when attacked

Red-Spotted Newt
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Reptiles
Copperhead

• 62 species in Virginia from 3 groups
  (30 snakes, 10 lizards including one
  introduced, 22 turtles)
• Antarctica the only continent without reptiles
• Snakes have no legs, but still tetrapods
• Evolutionary loss of legs
• Boas still maintain a pelvic girdle

Five-lined Skink
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Reptile Characteristics

• Ectothermic behavior
• Maintain a narrow temperature range
• Maintained through behavioral activities such as
  basking or burrowing
• Brummation
• Hibernation in ectotherms

River Cooters
Fence Lizard
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Crocodilians

• American Alligator not native to Virginia but
  is found just to the south in North Carolina

American Alligators
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Turtles
Snapping Turtle

• Vertebrae incorporated into shell
• Have a beak instead of teeth
• Omnivorous
• Temperature sex determination
• Found in a variety of habitats
• Marine
• Freshwater
• Terrestrial

Eastern Painted Turtle
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Lizards
Broadhead Skink

• Extremely diverse and variable
• Many islands have endemic species
• Endemic Species found in one location but no
  where else
• Do they all have legs?
• Glass Lizards/Leg-less lizards/Jointed Snakes
• How do you tell Glass Lizards from Snakes?
• Ear openings, eyelids, tail length

Slender Glass Lizard
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Snakes

• 30 species in Virginia
• 3 venomous species
• Copperhead, Cottonmouth, Timber Rattlesnake.
  
• Most species are non-venomous

Scarlet Kingsnake non-venomous
Ringneck Snake non-venomous
Copperhead - venomous
Black Rat Snake non-venomous
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Snakes

• All lack legs
• Lack ear openings
• Hear vibrations through the ground
• Shed their skin to grow

Eastern Hognose Snake
Ringneck Snake
Timber Rattlesnake
Redbelly Watersnake
Black Racer
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Snake Feeding

• Entirely carnivorous
• Swallow prey whole
• Can eat prey much larger than themselves
• Some use venom to immobilize prey
• Some constrict their prey
• Some actively forage for prey
• Some sit and wait for prey to approach them

Eastern Cottonmouth eating a mouse
Northern Watersnake eating a fish
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Snake Defense Mechanisms

• Crypsis Staying camouflaged
• When detected
• Flee, musk, gape, rattle
• When these do not work, snakes may strike
• This occurs only when a snake feels threatened
  and has no other option to protect itself

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Conservation
Grey Tree Frog

• Many amphibians are in decline
• 32 of amphibians endangered versus 12 of birds
  or 23 of mammals
• 43 of amphibian populations are declining
• Few populations are known to be increasing

Red Salamander
Eastern Kingsnake
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Causes of Decline

• Habitat destruction
• Disease
• Pollution
• Over-exploitation
• Climate change
• Invasive species
• How many are human caused?

Photos by Steve Price
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What can you do?

• Enjoy finding and observing amphibians and
  reptiles
• Dont keep wild amphibians and reptiles as pets
• Dont kill snakes
• Make sure you know a venomous species looks like
  before handling snakes, and NEVER touch or
  threaten a venomous snake
• Dont release any amphibian or reptile pet into
  the wild

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Questions?
Corn Snake