The Missouri River has been through many changes since the Corps of Discovery pulled boats up its shallow waters. The river Lewis called "a mile wide and an inch deep" has been severely dammed, straightened, and channelized over the last century, and such activities have shortened the river by more than 400 miles.
Despite this, the Missouri River hosts fantastic fish habitat. The lower Missouri, a free-flowing stretch that flows through South Dakota, Nebraska, Iowa, Kansas, and Missouri, offers hundreds of miles of muddy river teeming with fish. Dammed sections of the Missouri in South Dakota are popular because of the walleye. In other spots channel catfish and the predatory blue and flathead catfish get the most attention because of their size, sport, and tasty white meat, but many other fish live there also, including brim, blue gill, crappie, largemouth bass, white bass, and northern pike. The Niobrara and the Big Sioux rivers also remain full of fish. The habitat in the lower sections of these rivers offers a perfect environment for catfish and pan fish. Both these rivers offer outstanding access to fly fishing for introduced carp.
The Missouri River in South Dakota also maintains one of the last wild runs of this continent's oldest fish, the paddlefish. These relatives of the dinosaurs still swim in the Missouri, although their numbers have been decimated by over-harvest and habitat loss. In the early part of the century, anglers came from all over to harvest these fish for their delicious white meat, reducing their populations.
Later, dams drowned many miles of paddlefish habitat. Since South Dakota established a catch limit and fishing season for paddlefish, and state and federal governments have launched stocking programs, paddlefish numbers have slowly improved. Today a lottery system decides who gets to keep a paddlefish, but anyone can spend an afternoon watching anglers try to catch these ancient creatures.