riparian zones. Physical degradation could continue to 

 affect fisheries even if water quality improvements were 

 achieved. 



Less is known about the fishery from Milltown Dam to the 

 mouth of the Flathead River. DFWP has surveyed fish 

 populations in this reach and evaluated the importance of 

 tributaries as spawning areas only in the past few years. 

 Preliminary data suggest that the abundance of game fish is 

 considerably below other rivers of comparable size. The lack 

 of suitable spawning tributaries in this segment is thought 

 to be a major factor in limiting salmonid populations. 

 Water quality may also be a factor, as biologically sig- 

 nificant heavy metals contamination has occurred in the Clark 

 Fork below the Milltown Dam in high runoff years. 



The lower river fishery has been most affected by 

 physical habitat alterations. The hydropower dams and 

 reservoirs of the lower river have blocked fish migrations 

 and created relatively poor fishery habitat. The rapid water 

 exchange through the reservoir and fluctuating water levels 

 limit the biological productivity needed to sustain a larger 

 fish population. Early attempts to manage the reservoirs 

 exclusively for salmonids have been unsuccessful, but recent 

 introductions of cool-water species have shown some promise. 

 The availability of spawning areas for salmonids is limited. 

 Some tributary streams have subterranean flows in the lower 

 reaches that block spawning migrations; other streams are 

 scoured during spring runoff leaving poor spawning sub- 

 strates. 



The goals of a fisheries program for the Clark Fork are 

 to increase the abundance of game fish throughout the 

 mainstem and to identify and protect the habitat required to 

 sustain game fish production. Improving the Clark Fork 

 fishery requires action, especially on the part of DFWP, in 

 several separate, but related categories: 



1. Eliminate acute and chronic toxicity conditions in the 

 upper river. 



Design and implement a reclamation plan to prevent the 

 direct entry of precipitation runoff from streamside 

 tailings into the river. The reclamation plan should 

 utilize existing data and new information gathered for 

 this purpose (see "Floodplain Mine Wastes") . Government 

 agencies, private parties, and landowners should work 

 together on this plan. 



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