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Eastern Hognose Snake. Green Treefrog. Amphibians and Reptiles: An Introduction to Herpetofauna. Compiled by the Davidson College Herpetology Laboratory. Amphibians and Reptiles. Ectothermic Use outside energy sources to maintain body temperature for metabolism and regulatory functions
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Eastern Hognose Snake Green Treefrog Amphibians and Reptiles: An Introduction to Herpetofauna Compiled by the Davidson College Herpetology Laboratory
Amphibians and Reptiles • Ectothermic • Use outside energy sources to maintain body temperature for metabolism and regulatory functions • Cryptic • Very difficult to detect even though they can be highly abundant Fence Lizard River Cooters Northern Watersnake Timber Rattlesnake Timber Rattlesnake Eastern Diamondback Rattlesnake
Non-Tetrapod Vertebrates Frogs Salamanders Caecilians Reptiles Birds Mammals Eastern Diamondback Rattlesnake Tetrapods • Snakes have evolutionarily lost their legs • Humans evolved from one of the same ancestors of extant reptiles Adapted from the WhoZoo
Amphibians and Reptiles • Very important to the ecosystem • Prey and Predator • Prey item for animals including raccoons, opossums, and birds • Prey upon insects, mice, and rats • Bio-indicator • An animal that can indicate the health of an environment by its population structure and abundance Green Salamander Ringneck Snake Spring Salamander Eastern Spadefood Toad Green Anole
Amphibians • 88 Species in North Carolina • Highest 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
Grey Tree Frog Frogs • Tadpoles lose tails and grow legs as they metamorphose • True Frogs • Rana • Tree Frogs • Hyla • Toe pads Southern Leopard Frog Bull Frog Spring Peeper Upland Chorus Frog Green Tree Frog
Fowler’s Toad Toads • Similar to frogs • Tadpoles lose tail and grow legs as they metamorphose into adults • Less dependent upon water than frogs • Have warty skin • Paratoid Glands: • Glands behind the eye that secrete toxin American Toad
Salamanders • Plethodontids: No lungs • Obligate, aerobic respiration through the skin • Ambystomatids: Lungs • Facultative, aerobic respiration through the skin • Hellbenders • Grow to 2 feet in the USA, but up to 5 feet in Japan • Hidden gills Spring Salamander Marbled Salamander Photo by Kristen Cecala Hellbender
Spring Salamander Larva Redback Salamander Amphibian Breeding Locations • Streams • Adults utilize upland habitat for feeding • Use stream for breeding, larval period, and occasional foraging • Wetlands • Adults live and feed in upland habitat • Return to wetlands to breed and undergo larval periods • Terrestrial • Adults never require water for reproduction • No larval stage • Utilize moisture under logs and leaf litter
Caecilians • Live in the tropics • Leg-less and blind • Look very similar to a worm Caecilians
Upland Chorus Frog Frog eggs Pine Woods Tree Frog Tadpole Spring Peeper calling Cricket Frog Spring Peeper Tadpole/Metamorph Amphibian Life Cycle
Green Frog Tadpole Amphibian Defense Mechanisms American Toad • Toxin in skin • Toads and Newts • Producing large numbers of offspring • Producing noisy squawks when attacked Red-Spotted Newt
Copperhead Reptiles • 70 species in North Carolina from 4 groups • Antarctica the only continent without reptiles • Snakes have no legs, but still tetrapods • Evolutionary loss of legs • Boas still maintain a pelvic girdle American Alligator Broadhead Skink Eastern Painted Turtle
Reptiles • First vertebrates to become independent of water for reproduction • Some reptiles have reverted to aquatic lifestyles, but still reproduce without water • Sea Snakes • Swamp Snake • Snapping Turtle • Sea Turtles Black Swamp Snake Snapping Turtle
Reptiles • Ectothermic • Maintain a constant temperature range • Maintained by basking, movement, and shivering • Brummation = hibernation Yellowbelly Slider
Crocodilians • American Alligator • Osteoderms • Temperature Sex Determination • Sex of offspring determined by the temperature at which eggs are incubated American Alligators
Eastern Painted Turtle Snapping Turtle Turtles • Temperature sex determination • Vertebrae integrated into shell • No teeth: Beak similar to a bird • Omnivorous • 3 habitats • Marine • Freshwater • Terrestrial Loggerhead Sea Turtle Box Turtle
Eastern Diamondback Rattlesnake Green Anole Rough Green Snake Scarlet Kingsnake Squamata • Snakes and lizards • Jacobson’s organ • Olfactory organ • Tongue flicks out of the mouth and moves chemicals in the air to the organ • Extremely movable jaw
Fence Lizard Lizards Five-lined Skink • Extremely variable and diverse • Many endemic species • Leg-less Lizards • Glass Lizards or Jointed Snakes • Lizards have eyelids and ear holes that snakes do not Slender Glass Lizard Ground Skink
Snakes Eastern Diamondback Rattlesnake - venomous • 37 species in North Carolina • 6 venomous species • Copperhead, Cottonmouth, Coral Snake, Timber Rattlesnake, Eastern Diamondback Rattlesnake, and Pigmy Rattlesnake • Most species are non-venomous Scarlet Kingsnake – non-venomous Ringneck Snake – non-venomous Black Rat Snake – non-venomous
Redbelly Watersnake Snakes • All lack legs • Lack ear openings • Hear vibrations through the ground • Shed their skin to grow • Either lay eggs or give birth to live young Eastern Hognose Snake Ringneck Snake Black Racer Coachwhip
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 Diamondback Rattlesnake eating a Cottontail Rabbit Scarlet Kingsnake eating a Green Anole
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
Eastern Kingsnake Bog Turtle Conservation • 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 Grey Tree Frog Red Salamander
Causes of Decline • Habitat destruction • Disease • Pollution • Over-exploitation • Climate change • Invasive species • How many are human caused?
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 poisonous species looks like before handling snakes, and NEVER touch or threaten a poisonous snake • Don’t release any amphibian or reptile pet into the wild
Questions? Corn Snake