Nesting success has not been determined in any studies of the 

 Pacific coast population because no nests have ever been found in 

 any of the studies. Dzinbal did determine that the percentage of 

 failed-breeding females was 33% during 1979 and 43% in 1980 thus 

 nesting success could be interpreted to be 67% and 57% in those 

 respective study years. 



Wallen & Groves (1989) suggest that harlequin ducks are, at 

 best uncommon nesters in northern Idaho. Results of this survey 

 and surveys conducted on the Kootenai National Forest (Miller 

 1988 and 1989) suggest the same is true for western Montana. 



Habitat 



Harlequin duck habitat has been identified as low gradient, 

 mountain streams with dense shrubs along the streambank (Kuchel 

 1977, Wallen & Groves 1989). Observations of harlequin ducks 

 during this survey were within that habitat type. Stream data 

 gathered during this survey describe the stretch of stream 

 surveyed. Separate measurements of streams at observation 

 locations were not conducted. 



Harlequin ducks nested on only 2 streams surveyed in this 

 ^tudy, Trail Creek, where I located 2 broods and Sullivan Creek, 

 where I located 1 brood. The brood located on the Middle Fork of 

 the Flathead probably came from one of the creeks flowing into 

 the river in that area. Single females were located on Swift and 

 Wounded Buck creeks. 



Flow rates of these four creeks ranged from 77 cfs on 



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