and have growth rates that exceed marv of the state's other river 

 populations. Fluctuating river levels during reproductive stages 

 are apparently limiting the rainbow's population numbers. The 

 MDFWP is working with the Army Corps of Engineers to determine the 

 impact of the current dam operations on the downstream fishery, 

 and possible mitigation alternatives. In addition, the Corps is 

 studying the possibility of increasing power production at Fort 

 Peck with plans that include a re-regulatory dam that would flood 

 the dredge cuts and destroy the unique fisheries. 



Wildlife 



Slicing through unglaciated rough breaklands of nortlaeastern 

 Montana is the lower Missouri River. At the time of Lewis and 

 Clark, plains grizzly bears, wolves, the now extinct Audubon's 

 bighorn sheep, bison, plains elk, and black-footed ferrets roamed 

 the lower Missouri basin. However, with the encroachment of 

 civilization and the consequential loss of habitat and 

 overharvest, many of these animals were extirpated from the 

 region. Taking ten years to fill. Fort Peck Reservoir eventually 

 inundated nearly a quarter million acres of Missouri River 

 floodplain and breakland habitat. Simultaneously with the huge dam 

 project. President Franklin Roosevelt withdrew more than a million 

 acres of surrounding abandoned "dust bowl" lands to create the 

 Fort Peck Game Range in 1936, now renamed the Charles M. Russell 

 Refuge. 



From the head of Fort Peck Reservoir (but excluding the 

 reservoir itself) to the North Dakota border, the lower Missouri 

 basin is comprised of 17 assessment units (Table 53). Due to Fort 

 Peck Dam's inundation of most of the region's well-developed 

 riparian habitat, 83 percent of the lower Missouri's habitat 

 ratings fell into Class IV. The exceptions included the lower 

 Missouri River reaches from Fort Peck Dam to the Poplar River 

 (Class III) and from the Poplar River to North Dakota (Class II). 

 In the latter reach, Cottonwood gallery forests, islands, 

 backwater areas, and a variety of vegetation types are abundant. 

 Big Muddy Creek, which meets the Missouri from the north along the 

 eastern end of the Fort Peck Indian Reservation, also received 

 Class III habitat quality rating. 



Earning the only Class I species value in the lower Missouri 

 basin, the north side tributaries to Fort Peck Reservoir support 

 wintering bald eagles, historic peregrine falcon eyries, golden 

 eagles and other raptors, potential black-footed ferret re- 

 introduction habitat, and mountain and piping plovers. This basin 

 also gleaned more game species points than any other unit in the 

 lower Missouri. A population of re-introduced bighorn sheep still 

 occupy portions of this rough and isolated country. The Big Muddy 

 Creek drainage, which includes Medicine Lake National Wildlife 

 Refuge, has been used as a stopover for the endangered Whooping 



137 



