only 25-50 birds along the coasts of Washington and Oregon; there 

 also are scattered reports of harlequins wintering along the 

 coast of northern California (Bellrose 1980) . Occasionally 

 harlequins are sighted wintering inland in the Rocky Mountains 

 but these reports are rare (see Wallen 1987) . 



The breeding range of the western population extends inland, 

 following the Cascade and Sierra ranges south into northern 

 California, and the Rocky Mountain range west and south, across 

 northern Idaho and western Montana, into the northwestern corner 

 of Wyoming (Bellrose 1980) . Considered rare in Idaho (Burleigh 

 1972) , recent surveys have found breeding harlequins in several 

 drainages in the Idaho panhandle north of the Lochsa River 

 (Wallen and Groves 1988, 1989). In Montana, harlequins breed in 

 small numbers along the Rocky Mountain chain from Glacier 

 National Park (GNP) (Kuchel 1977) to Yellowstone National Park 

 (YNP) (T. McEneaney, pers. obs.) and scattered points in between 

 (D. Center, pers. obs.). Breeding harlequins also are known from 

 Grand Teton National Park (GTNP) , Wyoming (Wallen 1987) . 



Most detailed knowledge of harlequin duck breeding biology 

 has come from studies in Iceland (Bengston 1966, 1972) . In North 

 America, harlequin duck breeding chronology and breeding habitat 

 have been described for Prince William Sound, Alaska (Dzinbal 

 1982), Glacier National Park (Kuchel 1977), and Grand Teton 

 National Park (Wallen 1987) . 



Concerning breeding chronology, pair formation usually 

 occurs on the wintering grounds (Bellrose 1980) . In GTNP, Wallen 



