Arctic grayling or other trout were captured, although suckers, 

 dace, and sculpins were present in varying numbers. Sampling 

 occurred later in the season (Table 1) , so some spring use may 

 have gone unobserved. 



The smaller of the two irrigation ditches on Erb's Ranch 

 also had minimal use by fish of any kind. In addition to the 

 ubiquitous suckers and dace, only one brook trout YOY and one 

 mountain whitefish YOY were captured in the ditch. No Arctic 

 grayling (YOY or adult) were found in the ditch. 



The larger irrigation ditch on Erb's Ranch has a significant 

 flow throughout the summer (Table 1) . Twelve YOY and two adult 

 arctic grayling were captured, as well as several large brook 

 trout and burbot. Numerous YOY grayling were observed in schools 

 in the ditch, but only the twelve were secured. Electrof ishing 

 effectiveness may have been limited by low conductivity. 



There is a possibility of losing these fish during the fall 

 when the ditch is dewatered. This presents an exceptional 

 opportunity for testing an incremental dewatering of the ditch 

 and the effectiveness of this method in returning grayling to the 

 river. The landowner was very helpful in providing access and 

 may be amenable to testing an incremental shutdown. 



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