coniferous forests and wood land cover-types. Spawning areas all fall within (type V) 

 valleys formed from glacial scouring processes in which the resultant trough is a 

 relatively wide, U-shaped valley, with valley-floors slopes generally less than 4% 

 (Rosgen 2002). Soils are derived from materials deposit as morainal deposits, glacial 

 outwash and post-glacial alluvium. Geomorphic surveys identified all four spawning 

 areas as C4-type channels (Rosgen 2002). Geomorphic summaries, Wohlman substrates 

 size-classes and discharges measurements for the four study sites are located in Table 1 0. 



Redd measurements 



All 37 redds were found in depositional gravel-dominated bedforms, of which a 

 majority (24 or 65 %) were constructed in glide tail-outs in flow convergence zones 

 immediately upstream of riffle crests. The remaining (13 or 35%) redds were constructed 

 in riffles. Within these depositional areas, redd locations varied, with ten redds found in 

 mid-channel, 10 in the right and 17 in the left channel margins. Of those in charmel 

 margins, six were in side channels, and two in beaver influenced braided channels. Mid- 

 channel redds recorded the greatest distance from overhead cover averaging 8.9m, 

 compared to 5.6m for redds at other sites. 



Summary statistics for measured redds are outlined in Table 1 1 . From the sum of 

 measurements, the "average" redd is constructed in relatively shallow (~2 1 cm) water of 

 moderate approach velocities (7-8 cm/sec). The total length of the redd is ~192 cm, of 

 which the tailspill forms the majority (59%) and the pit the minority (41%) of the 

 completed redd. The tailspill is constructed 1 5 cm above the surrounding glide, while the 

 pit is a ~12 cm depression within the glide. Water approach velocity slows from 8.1 

 cm/sec to 7.0 cm/s within the pit, before accelerating 38% from the pit to the tailspill 

 crest (11.3 cm/s). The shape and velocities operate such that the pit collects "fines" 

 before they access the egg pocket (tailspill), while simultaneously forcing water through 

 the egg pocket. 



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