migratory nature of the fishery. Continued tagging efforts to 

 identify movement patterns will be important in directing 

 management strategies. 



Reach 4: Monture Creek to Belmont Creek 



The physical characteristics of this reach of the Blackfoot 

 River are similar to those in the lower segment of reach 3, below 

 the mouth of the North Fork. Monture Creek was chosen as a reach 

 break because the extensive rainbow trout recruitment from this 

 tributary marks the upper boundary of the Blackfoot River fishery 

 dominated by rainbow trout. Trout populations in this segment 

 were sampled in the Scotty Brown Bridge Section. No fisheries 

 information was collected in this reach prior to 1988. 



Based on habitat comparisons with other western Montana 

 rivers containing healthy rainbow/cutthroat trout fisheries, this 

 reach of the Blackfoot River appears to have outstanding 

 potential for supporting a fishery. The density of rainbow 

 trout over 5.0 inches in length, however, was only 142/mile 

 during sampling in fall, 1988. The majority of fish were 

 concentrated in deep pools, while long stretches of river 

 possessing favorable habitat were completely void of fish. 



Low streamflows during 1988 may have influenced habitat use 

 by trout and appeared to result in movement of fish from 

 traditional habitats to the deep pools. Pool seeking behavior 

 associated with low streamflows has previously been observed in 

 the Bitterroot River (Spoon 1987). Angler concerns over a 

 depressed fishery are warranted considering the low densities of 

 trout observed in the Scotty Brown Bridge Section. Apparent 

 trout movement from more typical habitats to pool areas would 

 likely decrease angler success and add to the perception that 

 trout numbers are very low. Relatively high water temperatures, 

 in excess of 70 F, may have also contributed to poor fishing. 



The reason (s) for low trout densities in this reach is not 

 clear. Rainbow trout YOY surveys found some of the highest 

 numbers of YOY in the Blackfoot River, indicating that 

 recruitment is not limiting the fishery. Based on adult 

 population surveys during the fall, it appeared that the large 

 numbers of YOY does not translate into an abundance of the 

 succeeding age class (yearlings) . Since yearlings (approximately 

 3 to 6 inches in length) are not generally harvested by 

 fishermen, natural mortality or movement of these juvenile fish 

 appears to occur in this segment of river. The ultimate fate of 

 rainbow trout YOY in this reach is in need of further study. 



Effects of trout harvest by fishermen should also be 

 evaluated in reach 4. Although low densities of trout in this 

 reach are not likely a result of overharvest, increased fishing 

 pressure in recent years has probably further depressed this 



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