2. The geography of Upper Thompson Lake (three basins that flow through narrow, shallow 

 channels and 90 percent of the lake less than 10 feet deep) make any fish (especially trout) 

 vulnerable to northern pike predation. 



3. Any exotic species planted in the Thompson Lake complex can potentially escape to the 

 Clark Fork River. 



Preferred Manngpmpnt Option; 



Management qjtions ccmsidoed included current management for pike/bass/perch, rainbow trout 

 stocking, catchable rainbow trout stocking, and artificial structure placement for bass. There were 

 203 comments on the Thompson lakes chain. 



Under the preferred management option. Upper Thompson Lake would be managed as a two- 

 tiered fishery with primary emphasis on warmwater fish (pike, bass) while maintaining 

 opportunities for trout, as feasible. FWP would initiate a comprehensive largemouth bass genetic 

 survey to determine future stocking needs. FWP would initiate structure enhancement for 

 largemouth bass. Large rainbow trout might be added to the lake as they become available. FWP 

 will propose allowing spearing of northern pike through the ice on Upper Thompson Lake to 

 provide some additional control on this illegally introduced fish and to provide an additional 

 angling experience in the TCL. 



RAINBOW LAKE 

 I<akft Pftscription: 



Rainbow Lake is a small closed-basin lake north of Upper Thompson Lake and east of Crystal 

 Lake. The maximum depth of Rainbow Lake is unknown (probably less than 75 feet) and it has 

 a surface area of 20 acres. Between March 1, 1993 and February 29, 1994, FWP estimated that 

 as many as 395 anglers, of which 100 percent were Montana residents, fished at Rainbow Lake 

 (Montana Statewide Angling Pressure Report), 



Tjike Mnnagempnf Sfntiisi 



Management of Rainbow Lake commenced in 1932 when 37,000 rainbow trout were planted 

 (Table 9). Though several other species have been planted, management of Rainbow Lake has 

 been primarily for rainbow trout. Unauthorized plants of largemouth bass and pumpkinseeds 

 occurred at least by the 1940s, and illegal yellow perch introductions soon followed. 



Gillnetting in 1992 indicated that rainbow trout planted in the previous year were relatively 

 abundant (5.0 pCT n^) and in good condition, although no holdover trout (greater than 12 inches) 

 were captured. Yellow perch are very abundant in Rainbow Lake (28 per net) and undoubtedly 



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