Wildlife and Natural Resources

Where the Mississippi River meets the Gulf of Mexico, the deposition of rich sediments and co-mingling of fresh river water and warm salt water gives rise to a spectacular flowering of life–a veritable frenzy of biological productivity. Even in its degraded state, the Mississippi River Delta teems with wildlife, supporting more than 400 bird species, threatened Louisiana black bears and other mammals, finfish and shellfish, reptiles and amphibians, and nearly unfathomable multitudes of smaller organisms that hold the entire food web together.

The delta is a vast and dynamic tapestry of forests, swamps, marshes, sloughs, river channels, estuaries and islands. Taken together, these habitats make up one of the largest and most productive wetland ecosystems in North America, but as the tapestry continues to unravel, more and more organisms lose the habitats they need to survive.


Brown pelicans (David J. Ringer, National Audubon Society)

The Mississippi River Delta supports more than 400 species of birds, providing critical breeding, wintering and migratory stopover habitat for 100 million individual birds each year, including approximately 5 million ducks and geese.

Bottomland hardwood forests and cypress-tupelo swamps in the upper reaches of the delta provide habitat for a host of neotropical migratory songbirds, ducks, wading birds and other forested wetland specialists, including the rapidly declining Rusty Blackbird. The delta’s fresh, brackish and salt marshes are home to terns, wading birds, shorebirds and secretive marsh birds, including Clapper Rails and Seaside Sparrows. And the delta’s islands support staggering concentrations of breeding waterbirds, including the Brown Pelican (Louisiana’s state bird), wading birds (herons, egrets, spoonbills, and ibises), terns, gulls and shorebirds.

For millions of birds that traverse the Mississippi Flyway each year, the delta’s food-rich habitats are the last stop before a grueling 500- to 600-mile nonstop flight across the Gulf of Mexico in the fall, or conversely in the spring, a desperately needed refuge for hungry and exhausted birds returning north across the Gulf. Thus, the collapse of the delta threatens not only its year-round residents but also some of North America’s most colorful and iconic backyard birds and other species, birds whose lives quite literally span the hemisphere, from the high Arctic tundra to Tierra del Fuego, and who depend on a healthy delta.


Courtesy of Department of Interior

Many mammals also rely on the delta’s habitats and food resources, from Louisiana black bears in forested regions to bottlenose dolphins in productive estuaries and even sperm whales in deep waters offshore where the delta’s abundance concentrates food resources for these marine giants.

At least 100 threatened Louisiana black bears live in the Atchafalaya Basin (the western side of the delta), where conservationists are working to protect them and provide habitat corridors to connect isolated bear populations.

Other mammals in the delta include minks, muskrats, beavers, armadillos, foxes, coyotes and bobcats. Introduced nutria (large rodents native to South America) and feral hogs are also present and often prove very destructive to native ecosystems and species.

Fish, shellfish, reptiles and amphibians

The delta’s estuaries and wetlands provide nurseries and spawning grounds for huge numbers of aquatic organisms, from commercially important seafood species (crawfish, shrimp, blue crabs, menhaden, drum and others) to alligator gar, paddlefish and the endangered pallid sturgeon. The delta’s once-great oyster reefs are today significantly reduced but still provide an important resource for other wildlife and for humans alike.

Though well known for its significant population of American alligators, the delta also provides vital habitat for other reptiles, including the Mississippi diamondback terrapin and several species of snakes and sea turtles. Frogs and toads of many varieties contribute to the delta’s “soundtrack,” especially on summer evenings, when their calls, bleats, croaks and trills can be almost overwhelming.