 <unk> of the lower Missouri waters has made the river narrower , deeper and less accessible to riparian flora and fauna . Numerous dams and bank stabilization projects have been constructed to facilitate the conversion of 300 @,@ 000 acres ( 1 @,@ 200 km2 ) of Missouri River floodplain to agricultural land . Channel control has significantly reduced the volume of sediment transported downstream by the river and eliminated critical habitat for fish , birds and amphibians . By the early 21st century , declines in populations of native species prompted the U.S. Fish and Wildlife Service to issue a biological opinion recommending restoration of river habitats for <unk> endangered bird and fish species . 
