cutthroat appear to be of the Yellowstone variety and probably have replaced 

 the native westslope variety as a result of stocking (Roscoe, unpublished 

 data). The cutthroat trout population in the study section was composed 

 mainly of larger fish (6 inches or longer) suggesting that reproducing 

 populations of cutthroat may be found in otherportions of the stream or its 

 tributaries. 



4. FLOW RECOMMENDATIOfIS 



Cross sectional data were collected from a 151 foot riffle-run-pool 

 sequence located approximately at stream mile 7 (74N, RlOW, Sec 31B). Five 

 cross sections were placed within the sequence. The WETP program was 

 calibrated to field data collected at flows of 27.2, 14.6 and 2.7 cfs. 



The relationship between wetted perimeter and discharge for a composite 

 of two riffle cross section is shown in Figure 13. Lower and upper inflection 

 points occur at 5 and 8 cfs. Based on an evaluation of the existing fishery 

 and recreational use, a flow of 6 cfs is recommended for the low flow period 

 (July 1 - April 30). Due to a lack of long term flow data, recommendation 

 for the high flow period (May 1 - June 30) cannot be derived. 



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