the only island in the river below the Falls (E), but they were most 

 often seen in the section of river (M and N) from Williams Creek to the 

 head of the Falls. Common goldeneye usually nest in cavities in deci- 

 duous trees (Bell rose 1976). Along the Kootenai River this type of 

 habitat occurs in the riparian zone. An unverified brood was reportedly 

 seen June 12, 1978, by fisheries biologist Brad Shepard. In 1979, 

 Common Goldeneye were often seen in fast water and, in winter, in large 

 pools sheltered by rocks. They were observed courting in winter and 

 spring when their numbers were highest. By June, observations of Common 

 Goldeneyes ranked behind those of Mallards (Table 5). It appears that the 

 project area is more heavily utilized by the common goldeneyes as a 

 wintering area than a breeding area. This could be due to the avail- 

 ability of fast-flowing ice- free water and resultant available food in 

 winter. During spring and summer, numbers decreased but the common 

 goldeneye remained on the study area during the nesting season. 



Barrow's Goldeneye . In 1978, Barrow's goldeneye were first observed 

 April 30 and were last observed June 5. No more than two birds were ob- 

 served on any one occasion although at least two males and one female 

 were present and used the bay area immediately above the Falls (M). 

 These birds were apparently transients. Nesting habits of the Barrow's 

 goldeneye are similar to those of the Common goldeneye. None were seen 

 in 1979. 



Herlequin Duck . One of the most unusual species encountered in 

 this study was the harlequin duck. Rare and local in its distribution 

 throughout Montana (Skaar 1975), this species is a highly stenotopic 

 "K-selected" species, and is restricted to turbulent, fast-flowing 

 mountain stream habicat. According to Kuchel (1976), the harlequin 

 duck's "precise ecological requirements and extreme sensitivity to human 

 intrusion limit breeding activities to remote, pristine areas." While 

 not formally recognized as a threatened or endangered species, the 

 harlequin duck is rare throughout its range, and became extinct in 

 Colorado in the early ISOC's (Kuchel 1976), although a breeding popu- 

 lation has recently become re-established there (Nelson and Parkes 

 1976). A small population, consisting of at least 7 individuals in 

 1978 and 3 in 1979, was found to be closely associated with the Falls 

 (Table 10). In 1978, the population consisted of one pair, a lone 

 female, and four bachelor males; while observations were made in river 

 sections G, H, I, J, L, M, and N, most birds were seen feeding in swift 

 water at the head of the Falls (L) or loafing on exposed rocks at or 

 just above the head of the Falls (M). All 7 birds were seen loafing 

 together, forming a "club" of both paired and unpaired birds as described 

 by Bengtson (1966:84). The rushing water at the head of the Falls, 

 where the river first begins to break over the rocky benches, was a 

 preferred feeding site. Harlequins feed almost exclusively on aquatic 

 insect larvae (Bengt:.on and Ulfstrand 1971, Bengtson 1972, Kuchel 1976). 

 Simuliidae (Diptei^a) were the major food source in Iceland, and while 

 Orthocladiinae were found to be much more abundant dipterans in bottom 

 samples taken in the Kootenai Falls area, Simuliidae were dominant in 

 substrate basket samples (Graham 1979) and are probably abundant in the 



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