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 an increase; all populations are relatively small 

 (Cassirer 1995). In Montana, the long term trend appears 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 Historic Changes); however, this has not 

 been statistically analyzed. In Wyoming, breeding populations appear stable in Grand Teton 

 National Park (Harlequin Duck Working Group 1993). 



POPULATION REGULATION 



A simple model using guesstimates for values of survival and fecundity was developed by 

 Goudie and Breauh (1994). It estimated that at 85% aduh survival, the population would grow at 

 6%/year. Simulations indicate that the model was most affected by aduh survival; an increase of 

 3% mortality may not be sustainable over the long term (Goudie and Breault 1994). 



CONSERVATION AND MANAGEMENT 



EFFECTS OF HUMAN ACTIVITY TO HARLEQUIN DUCK POPULATIONS, 



REPRODUCTION, AND BEHAVIOR 



Disturbance on the breeding grounds. On and near shore. Kuchel (1977) found that broods 

 less than 4 weeks old avoided areas with human access and selected areas that were distant from 

 access and inaccessible (p<0.05) on McDonald Creek in Glacier National Park. This was not true 

 of adults during May and early June when fewer park visitors were present. More recently, 

 Ashley ( 1 994) found Harlequins used inaccessible areas in greater proportion than their 

 availability, though not significantly so; his data is conservative in that surveys took place in the 

 early morning prior to the vast majority of visitor use. Most Harlequins left accessible stream 

 reaches when visitor use reached more than minimal levels. Ashley (1994) found males were 

 displaced by human activity to a greater extent than females. He speculated that this may be due 

 any or all of three reasons. First, females were likely born in Glacier National Park with its many 

 visitors, and are more habituated to humans than males which were likely born at other locations. 

 Second, females spend more time each year, during higher visitation periods, than males on 

 McDonald Creek and may be more habituated to human contact. Third, females are more 

 cryptically colored and less likely to attract casual visitor attention. 



On the Rocky Mountain Front in Montana, only 1 5% of sightings were in areas that were 

 inaccessible (>50 m fi"om established areas of human activity, not accessible by trail) (Diamond 

 and Finnegan 1993). Of the accessible areas, 5 1% were >50 m from a trail, 21% were 10-50 m 

 from a trail and 13% were <10 m from a trail; it should be noted that >90% of this area is 

 roadless. Visitor use is highest along the South Fork Sun River, where monthly trail use is 500 

 people in July and August (Diamond and Finnegan 1993). 



In Grand Teton National Park, Wyoming, 95% of Harlequin observations were in backcountry 

 areas, accessible only by trail (Wallen 1987). Within the backcountry however. Harlequins used 

 areas with moderate (5-9 people/day) to heavy (>10 people/day) human use more than lesser used 

 areas; Wallen (1987) suggested that may have been the result of the presence of many high 



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