The following sections provide a suTtimary of the current 

 fishery in the upper, middle, and lower segments of the 

 Clark Fork. Fishing trends in the basin and benefits and 

 costs to the region are also discussed. A list of fish 

 species in the Clark Fork Basin is given in Table 2-15. 



Upper Clark Fork Fishery (Headwaters to Milltown Dam) 



Fish Species Composition 



Brown trout are recreationally significant throughout 

 the upper river, and rainbow trout are abundant in the 

 sections immediately upstream from the mouth of Rock Creek 

 and downstream to Milltown. A few cutthroat, brook, and 

 bull trout occur and are presumably outmigrants from the 

 tributaries. Mountain whitefish and coarsescale suckers are 

 common throughout the segment. Redside shiners, longnose 

 dace, and sculpins are distributed in suitable habitats 

 within the segment. Squawfish are found from Drummond 

 downstream. 



For nearly a century, the upper river was barren of 

 trout due to the toxic materials released by mining, milling, 

 and smelting operations. Trout were observed in the river 

 during the 1960s, but populations of brown trout were not 

 established until the 1970s. Development of the uppermost 

 populations of brown trout near Warm Springs began 

 immediately after the installation of the Anaconda Company's 

 treatment pond No. 3 in the late 1950s. Populations of brown 

 trout throughout the upper river seem to have been relative- 

 ly stable over the 1970-88 period with the exception of the 

 Warm Springs area. The population of brown trout in the Warm 

 Springs river section (known as the pH shack section) has 

 increased rather steadily to the present level (Knudson 1984; 

 Spoon 1988) . 



Trout Population Estimates 



In 1987, the Clark Fork, from its origin at Warm Springs 

 to Milltown, was divided into segments and the population of 

 trout in each was estimated. Some 6,000 trout were tagged. 

 During the fall of 1987, spawning data on Clark Fork brown 

 trout were collected by electrof ishing in potential spawning 

 tributaries. A fish trap was placed above the mouth of the 

 Little Blackfoot to monitor upstream movements of spawning 

 fish from the Clark Fork. These efforts produced a plethora 

 of information that has not yet been fully analyzed. 



2-28 



