Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Amphibians and Reptiles: An Introduction to Herpetofauna Compiled by the Davidson College Herpetology Laboratory Edited for Virginia by Mike Clifford, Virginia Herpetological Society Eastern Hognose Snake Green Tree Frog Amphibians and Reptiles Ectothermic Regulate temperature from outside sources Water temperature Basking Yellow-bellied Slider Northern Watersnake Amphibians and Reptiles Cryptic Very abundant but their presence is largely unknown Timber Rattlesnake Timber Rattlesnake Northern Copperhead Amphibians and Reptiles Important to the ecosystem An important prey item for: Raccoons, opossums, birds An important predator of: Mice, rats, insects Spring Peeper Ringneck Snake Spring Salamander Green Salamander 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 Amphibian Characteristics Permeable skin Good olfaction Permeable: allows the transfer of oxygen and carbon dioxide to allow respiration Can allow the uptake of chemicals in the environment Green Frog Olfaction: Sense of smell Prey upon: Insects, other amphibians, anything small enough to fit into their mouths, even mice Spring Salamander Frogs Tadpoles when they are born Lose their tails as adults Two main types: Spring Peeper Metamorph True Frogs Bronze Frog Upland Chrous Frog Pickerel Frog Tree Frogs Toe-pads Green Tree Frog Grey Tree 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 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 Spring Salamander Marbled Salamander Two-lined Salamander Caecilians Live in the tropics Leg-less and blind Look very similar to a worm Caecilian Caecilian Amphibian Life Cycle Upland Chrous Frog Frog Eggs Pine Woods Tree Frog Tadpole Spring Peeper Cricket Frog Spring Peeper Metamorph Amphibian Defense Mechanisms Poison in skin American Toad Toads and Newts Producing large numbers of offspring Producing noisy squawks when attacked Red-Spotted Newt Green Frog Tadpole 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 Eastern Painted Turtle 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 Turtles Vertebrae incorporated into shell Have a beak instead of teeth Omnivorous Temperature sex determination Found in a variety of habitats: Marine Freshwater Terrestrial Olive Ridley Sea Turtle Snapping Turtle Box Turtle Eastern Painted Turtle Lizards Extremely diverse and variable Many islands have endemic species Endemic: Species found in one location but no where else Do they all have legs? Broadhead Skink Glass Lizards/Leg-less lizards/Jointed Snakes How do you tell Glass Lizards from Snakes? Fence Lizard Slender Glass Lizard Ear openings, eyelids, tail length Slender Glass Lizard Snakes 30 species in Virginia 3 venomous species Copperhead, Cottonmouth, Timber Rattlesnake. Scarlet Kingsnake – non-venomous Most species are nonvenomous 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 Black Racer Redbelly Watersnake Eastern Hognose Snake Ringneck Snake Timber Rattlesnake 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 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 Cottonmouth Eastern Diamondback Rattlesnake Eastern Hognose Snake Brown Watersnake 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