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Eastern Hognose Snake. Green Tree Frog. Amphibians and Reptiles: An Introduction to Herpetofauna. Compiled by the Davidson College Herpetology Laboratory. Edited for Virginia by Mike Clifford, Virginia Herpetological Society. Amphibians and Reptiles. Ectothermic
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Eastern Hognose Snake Green Tree Frog Amphibians and Reptiles: An Introduction to Herpetofauna Compiled by the Davidson College Herpetology Laboratory Edited for Virginia by Mike Clifford, Virginia Herpetological Society
Amphibians and Reptiles • Ectothermic • Regulate temperature from outside sources • Water temperature • Basking Yellow-bellied Slider Northern Watersnake
Timber Rattlesnake Timber Rattlesnake Amphibians and Reptiles • Cryptic • Very abundant but their presence is largely unknown Northern Copperhead
Spring Peeper Spring Salamander Green Salamander Amphibians and Reptiles • Important to the ecosystem • An important prey item for: • Raccoons, opossums, birds • An important predator of: • Mice, rats, insects Ringneck Snake
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
Green Frog Spring Salamander 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
Spring Peeper Metamorph Bronze Frog Green Tree Frog Grey Tree Frog 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
Toads • Similar to frogs • Tail-less as adults • Warty skin • Have large glands behind each eye that secretes toxin American Toad Fowler’s Toad
Spring Salamander Marbled Salamander Two-lined Salamander Salamanders • Plethodontids: Don’t 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
Caecilian Caecilian Caecilians • Live in the tropics • Leg-less and blind • Look very similar to a worm
Upland Chrous Frog Frog Eggs Pine Woods Tree Frog Tadpole Spring Peeper Cricket Frog Spring Peeper Metamorph Amphibian Life Cycle
Green Frog Tadpole Amphibian Defense Mechanisms American Toad • Poison in skin • Toads and Newts • Producing large numbers of offspring • Producing noisy squawks when attacked Red-Spotted Newt
Eastern Painted Turtle 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
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
Crocodilians • American Alligator – not native to Virginia but is found just to the south in North Carolina American Alligators
Box Turtle Olive Ridley Sea Turtle 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
Fence Lizard Slender Glass Lizard 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
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
Snakes • All lack legs • Lack ear openings • Hear vibrations through the ground • Shed their skin to grow Eastern Hognose Snake Ringneck Snake Timber Rattlesnake Black Racer Redbelly Watersnake
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
Cottonmouth Eastern Diamondback Rattlesnake Eastern Hognose Snake Brown Watersnake 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
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
Causes of Decline • Habitat destruction • Disease • Pollution • Over-exploitation • Climate change • Invasive species • How many are human caused? Photos by Steve Price
What can you do? • Enjoy finding and observing amphibians and reptiles • Don’t keep wild amphibians and reptiles as pets • Don’t kill snakes • Make sure you know a venomous species looks like before handling snakes, and NEVER touch or threaten a venomous snake • Don’t release any amphibian or reptile pet into the wild
Questions? Corn Snake