· Life in the Big Water
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
· Looking Ahead

Global 200 Snapshot

The Lower Mississippi River is distinguished by its extraordinary number of species. Many are specially adapted to conditions in the big river. Since glaciers did not reach this far south during the last Ice Age, this area served as a refuge for many species and allowed their survival.  

Life in the Big Water

Long before the first steamboat traveled the Mississippi, the native Algonquian people gave the river its name, which means "big water." Many of the earliest explorers on the continent traveled here, and today the river is still an important transportation route. The Mississippi’s rich waters are shared by big river species of fish, aquatic reptiles, amphibians, and crayfish and other invertebrates. Some of the fish species swam in these waters when dinosaurs walked the land.

Special Features

At its widest point the Mississippi is 4,495 feet (1,370 m) across, but it can expand many times that distance during floods. The Lower Mississippi flows through the Gulf Coastal Plain. It is surrounded by the Appalachian, Ozark, and Ouachita mountains, which, over evolutionary time, have formed a barrier that keeps species from entering or leaving the basin. Other large rivers flow into the Mississippi, including the Missouri, Big Black, Tensas, White, and Arkansas.

	At the end of the Ice Age 10,000 years ago, glaciers melted all over the world. The current channel of the Mississippi River was determined by the flow of ice-melt from glaciers in the upper Mississippi basin.

Wild Side

Many fish in the Lower Mississippi are specially adapted to conditions in the large, fast-flowing water and floods of this river, including five lamprey, the only North American paddlefish, four gar, bowfin, and four sturgeon. The pallid sturgeon and pallid sturgeon chub are found only in the main channel of the Mississippi and its large tributaries. Paddlefish and sturgeon are considered "living fossils" because fossils of this order date from the Jurassic period (195 million to 135 million years before the present). Paddlefish have a long snout that is flattened like a paddle and that has many tiny organs that probably detect electrical signals from their prey. More than 60 species of mussels and nearly 60 species of crayfish also live here. The lowest part of the Mississippi feeds into the Gulf of Mexico, from which many marine species enter the river. Tributaries contain minnows, catfish, cavefish, killifish, and darters. The American alligator can be seen along the Mississippi, and two types of turtles, the ringed map and the yellow-blotched map, are found nowhere else in the world.

Cause for Concern

Much of the forest along the Mississippi has been cleared for agriculture. Large amounts of chemicals and waste from farms contaminate the river and harm the fish and other animals that live there. Channelization of the river and the building of dams and levees to control flooding have changed the natural flow of the river and caused the loss of floodplain habitats along large portions of the river.

Looking Ahead

Fortunately, many individuals and organizations are working hard to keep the Mississippi clean and to preserve the species that live there. They are advocating the use of fewer chemicals to grow food and raise livestock and the proper disposal of waste from farms and cities, all of which would reduce the pollution of the river. They are also recommending the removal of dams and levees, which could help the river to flow freely again. (After a big flood in 1993, some broken levees along the Mississippi were not repaired so that wetlands, which provide natural flood control, could be restored.) Efforts have begun to reforest abandoned farmlands and restore the bottomland forests that used to border the river.