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During the expedition, the Corps of Discovery encountered several different species of the sturgeon, one of the Earth’s oldest fish believed to have originated about 70 million years ago.

Native to the Missouri and lower Mississippi Rivers is the pallid sturgeon – a fish that’s often called ugly or “prehistoric.” Sadly, in 1990, the U.S. Fish and Wildlife Service placed the pallid sturgeon on the endangered species list. It was the first fish species in the Missouri River drainage area to be listed as endangered, and a loss of its habitat is thought to be responsible for its decline. The vast majority of the Missouri River drainage system has been channeled and dammed, reducing the gravel deposits and slow-moving side channels that are the fish’s favored spawning areas.

Closely related to the more common shovelnose sturgeon, the pallid sturgeon is much larger, averaging between 30 and 70 inches in length, and weighing up to 85 pounds. The species takes about 15 years to reach maturity and can often live for up to 100 years. As with other sturgeon, pallid sturgeon lack the scales or bones found in more "modern" species of fish. Instead, they have cartilaginous skeletons with five rows of thick cartilage plates that extend along their sides, undersides, and backs, as well as over most of the head. These thick cartilage plates are covered by the skin and serve as a protective armor.

Due to the efforts of federal and state agencies, the fish is slowly working its way back. Here’s an interesting podcast on the status of the pallid sturgeon from the U.S. Fish and Wildlife: https://youtu.be/THOckhZArds

Watch Ranger Shannon with Lewis and Clark National Historic Trail talk about the pallid sturgeon and how we can keep them safe: https://youtu.be/Uhcwe-SMkTU?list=TLPQMDMxMDIwMjBLC45tmCJ-Sw

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  • Lewis & Clark National Historic Trail

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