World Wildlife Fund

More than 250 species of crayfish, nearly 300 species of mussels, and over half of all freshwater fish species in the United States are found in the waters of the Southeast. Many native species are found in a single stream or watershed.

In addition to fish and mollusk species, the region’s varied freshwater habitats sustain numerous species of birds, mammals, reptiles and amphibians. Some of the better known species include the wood stork - North America's only stork, the North American river otter, American alligator, ringed map turtle and the alligator snapping turtle - which can exceed 300 pounds and live more than 100 years.

Wood stork
© WWF-Canon / Fritz PÖLKING

Wood stork

The endangered wood stork lives in wetlands in Florida, Georgia, and Louisiana. As swamps and wetlands in their range have diminished, so has the number of wood storks. It was placed on the endangered species list in the United States in 1984.

These gregarious birds often soar high above the ground in flocks of 100 or more on their way to feeding areas. Wood storks capture their prey (fish, reptiles, frogs, and water invertebrates) with a technique called grope-feeding. The bird, wading in water up to its belly, moves its partly open bill from side to side in the water, snapping it shut as soon as something brushes up against it. The average time for this reflex is 25 milliseconds - one of the fastest known in vertebrates.

North American River Otter

Prized for its thick, durable fur, the North American river otter was once hunted nearly to extinction. By the mid-20th century it was common only in the coastal areas of the southeastern United States.

Today, thanks to conservation efforts, river otters are gaining a foothold in the region, although they are still threatened by habitat decline from land development, water diversions, pesticide use, and other disturbances.

River otters are perfectly suited to life in the water, although they are also often found on land. They have long bodies, short legs, and webbed feet. They eat fish, shellfish, frogs, birds, eggs, small mammals, and plants.

American alligator
© WWF-Canon / Martin HARVEY

American Alligator

One of only two true alligator species, the American alligator is found only in the southeastern United States, where it usually lives in slow-moving freshwater rivers and swamps, marshes, and lakes. 

Adult male alligators can reach 20 feet long and weigh half a ton. They feed mainly in the water, eating a wide variety of prey from fish to small mammals. Endangered in the early 1960s from years of hunting, pesticide use, and habitat loss, the alligators have rebounded, due to successful conservation efforts. Today most American alligator populations are healthy.

Alligator snapping turtle

Native to the southeastern United States, the alligator snapping turtle can live to be 50 to 100 years old and grow to weigh more than 200 pounds. It is the largest freshwater turtle in North America.

Alligator snapping turtles spend most of their time in the water, feeding on just about anything they can catch. To hunt fish, the turtles use a peculiar wormlike appendage on their tongues. The turtle opens its mouth underwater, and when a fish ventures in to catch the dangling "worm," the turtle snaps its mouth shut.

Alligator snapping turtles, often caught for their meat and for export to Asian markets, are threatened in every state in the southern United States because of unregulated harvesting. It is estimated that 70,000 freshwater turtles, including alligator snapping turtles, are collected and sent to Asian markets every year. Habitat loss is also a concern.