GRAYLING SPAWNING REPORT 



MOVEMENT ASSESSED USING TAG RETURNS 



A total of 30 grayling were recaptured during this sampling. 

 Twenty of these recaptures were tagged within the same year 

 (1988) and ten were tagged in previous years (Table 4). Of the 

 ten grayling tagged during 1987 and recaptured during our 

 sampling, five were tagged m the river between Fishtrap Creek 

 and Sportsmen's Park either during the previous Hay or November, 

 four were tagged in the Wisdom area during the previous May, and 

 one was tagged in Deep Creek the previous October (Figure 6 — A). 

 All fish tagged during the winter (November) and recaptured 

 during our spring sampling had moved up river. Subsequent 

 returns of seven fish tagged during our spring elec trof ishing by 

 anglers found that over half the fish tagged and recaptured (four 

 of seven) moved down river as far as the Divide Dam and the 

 longest recorded down river movement was 51 miles (Figure 6 - B). 

 The other three were captured in the Wisdom area from May to 

 early July. To summarize this tag return data, during 1938 the 

 majority of mature-sized grayling (fish 8.0 inches and longer) 

 moved upstream in the early spring to spawning areas (primarily 

 from the North Fork up to Wisdom) from wintering areas within the 

 lower river (from as far downstream as Divide Dam), spawned, and 

 then moved dov^n river or into tributaries after spawning (Table 4 

 and Figure 6). During past years mature-sized grayling spent the 

 entire summer within the upper portion ot the drainage in the 

 Wisdom Area. as documented by summer and fall electrof ishing 

 (Liknes 1978; Oswald 1984; Oswald 1986). 



CHARACTERISTICS OF SPAWNING SITES 



Visual Characteristics 



Grayling usually were found spawning in riffle areas over 

 gravel which appeared "bright" due to the absence of periphyton 

 and/or siit and sand sized material on the surface of the 

 streambed. These riffle areas of "bright" gravel were often 

 associated with recently created side channels, below beaver dams 

 and irrigation diversion structures, and/or near mouths' cf 

 tributaries where alluvial gravel fans had formed. Mature 

 grayling were collected near each riffle of clean gravel below 

 every beaver dam in a recently formed side channel belovvj Wisdom 

 which contained numerous beaver dams. 3y the (Tiiddls of the 

 spawning season elec trof ishers became relatively efficient at 

 identifying areas inhere ripe grayling were likely to be captured. 

 These areas could be characterized as being m areas of hydro- 

 logic instability, often in recently cut side c^■annels where a 

 riffle with "bright" gravel was situated near a pool or run. 



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