depressions in the streambed immediately below a shallow riffle. 

 These types of capture sites indicate that these fish may have 

 been 'herded' upstream into these areas from habitat they 

 actually preferred. In similar fashion, fish captured while 

 electrof ishing downstream tended to be concentrated in areas that 

 provided them with cover and occasionally that served as some 

 sort of visual barrier to further downstream movement. Whether 

 the shallow riffles were actually visual barriers, or whether the 

 grayling did not feel secure crossing them is not known, but they 

 rarely would move through these riffle areas. 



For 3 3 YOY grayling captured in grids, the mean distance to 

 the nearest upstream riffle was 74.5 ft, while the mean for the 

 fish collected while electrof ishing upstream (sample of 35) was 

 only 39.2 ft (Table 4). The YOY grayling collected while moving 

 downstream (sample of 42) were an average of 158.5 ft below the 

 nearest upstream riffle. A similar, though inverse, relationship 

 is seen in the values presented for the distances above the 

 nearest downstream riffle, the grid fish are intermediate in 

 distance while the fish collected while moving downstream are 

 closest and the fish collected while moving upstream are furthest 

 from the downstream riffle. This indicates that these YOY 

 grayling may have been displaced by the presence and movement of 

 the electrof ishers and that the grid method may provide more 

 accurate results with respect to microhabitat information. 



The typical macrohabitat area parameters that appeared in 

 all 'intensive-use areas' were, 1) a sloughing outside bank, 

 providing soil clumps of varying size and age, 2) at least one 

 pool area with depths in excess of 1.5 ft, 3) presence of 

 extensive mats of aquatic vegetation, 4) proximity to a riffle 

 with relatively loose substrate particles that may have served as 

 spawning habitat for adult grayling, and 5) streambanks. 



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