Mountain-Prairie Region





Vol I, No. 4.


4. The Pallid Sturgeon, a Missouri River "Dinosaur"

Deserved or not, the pallid sturgeon might best be known as one of the ugliest fish in North America.

This unusual inhabitant of the Missouri and Mississippi rivers evolved from a group of fishes that were dominant during the late Cretaceous period 70 million years ago, when dinosaurs roamed the earth. With its flattened shovel-shaped snout, bony plates and long reptile-like tail, the pallid sturgeon even looks like a dinosaur.

The fish is similar in appearance to its more common aquatic cousin, the shovelnose sturgeon. Like other sturgeon, the pallid's mouth is toothless and positioned under the snout for sucking small fish and other food items from the river bottom. Its known habitat extends from the Missouri River in central Montana to St. Louis; the Yellowstone River of eastern Montana; and the Mississippi River from St. Louis to the Gulf of Mexico.

The pallid sturgeon is one of the largest fish found in these river systems. Old reports and photographs document fish weighing more than 80 pounds and reaching lengths of six feet.

Withstanding events that caused extinctions of many other fishes, the pallid sturgeon managed to survived over the millennia. Yet in spite of its tenacity, its future is uncertain. In 1990, the U.S. Fish and Wildlife Service (USFWS) added the pallid sturgeon to the federal endangered species list, which is reserved for species in danger of extinction.

Populations of the pallid sturgeon are now so small that the big fish are rarely seen or caught by anglers. The primary reason for their decline is believed to be habitat loss caused by man.

Pallid sturgeon evolved for millions of years in a natural river system. These waters had meandering, braided channels and backwaters that provided different depths and flow velocities. But today, the pallid's habitat is altered by dams that modify flows, reduce turbidity and lower water temperatures. The river habitats of the Missouri and Mississippi also have been altered by various channels and construction of dikes that narrow the rivers and cut-off backwater areas.

The pallid sturgeon was the first fish species of the Missouri River identified as needing a protection and recovery plan under the Endangered Species Act. The imperiled status of this species is a result of alteration of the natural habitat of the Missouri and Mississippi rivers. And like a canary in a coal mine, the plight of the pallid sturgeon serves warning that the overall health of the ecosystem has suffered.

Species interact in complex ways, and survival of all native species in a given region is an indicator of a healthy ecosystem. If one species declines, others can become negatively affected. Recovery programs for any species, such as the pallid sturgeon, aim to restore the critical balance that exists between all members of a healthy ecosystem.

Besides its importance as a natural member of the Missouri and Mississippi river systems, the pallid sturgeon has economic benefits for society. Anglers who have landed an 80-pound pallid sturgeon claim it to be an exciting, rewarding gamefish. If recovery efforts are successful, the fish may become delisted and available once again for sportfishing.

The pallid sturgeon might be considered ugly to some, but to most its recovery would be nothing less than beautiful.

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