Table 8. Estimated numbers of Harlequin Ducks. 



® After Cassirer et al. (1996) except for Montana (see text) 



Trends. Little long or short term data is available. In Montana, the long-term trend 

 appears to be downward. Occurrences with larger populations (>5 pairs) appear to be stable over 

 the last 4-8 years, while some small occurrences appear to be declining or have recently gone 

 extinct (see DISTRIBUTION - HISTORICAL CHANGES); however, this data has not been 

 statistically analyzed. In general, the recent North American Pacific populations trend is not 

 clear-cut but generally appears to be declining. Christmas bird counts in British Columbia show 

 declines at 5 locations and increases at 3; the increases, however, may be due to increasing 

 numbers of observers in urban areas (Harlequin Duck Working Group 1993). In Alberta, 

 breeding Harlequins are significantly declining on the Maligne River in Jasper National Park 

 (Harlequin Duck Working Group 1993). Seven streams in Northern Idaho appear to be stable, 

 though 1 stream shows a decrease and one shows an increase; all populations are relatively small 

 (Cassirer 1995). In Wyoming, breeding populations appear to be stable in Grand Teton National 

 Park (Harlequin Duck Working Group 1993). In Alaska, a major population in Prince William 

 Sound has been decimated by the Exxon Valdez oil spill (Goudie et al. 1994). The Asian Pacific 

 population appears to be declining rapidly in eastern Siberia (Goudie et al. 1994). 



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