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Every habitat on the planet is home to a unique complex of species. Learn more about the animals that live in:

Also called the “water moccasin,” the cottonmouth snake inhabits lakes, streams, marshes, rivers, and swamps across the southern and southeastern United States. The large, heavy-bodied snake can grow longer than 6 feet and is covered in dark brown, black, or olive-green scales. Ill-tempered, the cottonmouth is reluctant to vacate the logs and stumps on which it basks, instead opening its mouth in a wide gape, displaying the white interior for which it is named as a warning. Cottonmouths spend almost their entire life in or around water. They swim with ease, holding their heads above the surface. In winter, they hibernate under stumps, in rocky wooded hillsides, or burrows created by other animals like beavers, muskrats, tortoises, or crayfish.

Usually active at night, the snake preys on almost anything it can catch, including frogs, fish, lizards, young alligators, other snakes, birds, turtles, and mammals. A relative to the copperhead, the cottonmouth is a pit viper. Its venom is hemolytic, meaning that it destroys red blood cells and coagulates blood around the bite. Though bites are rarely lethal to a healthy adult, they are more than sufficient to deal with small prey.

While larger females may mate every year, cottonmouths usually breed every other year, typically in August or September. They bear litters of as many as 15 young, each 7 to 13 inches. Young cottonmouths often display banded patterns, their skin becoming muddy and dark as they age. If not eaten on by alligators or other animals or killed on roads, they reach sexual maturity at 3 to 4 years.