America region. 



PRIORITIES FOR FUTURE RESEARCH 



The following are among the highest fliture research priorities and are primarily a subset of those 

 listed by the Harlequin Duck Working Group (1993) and Cassirer et al. (1996). 



1) What are the impacts of human disturbance on breeding and wintering Harlequin Ducks? 



Several independent studies have documented the sensitivity of Harlequin Ducks to human 

 disturbance, primarily through the relationship of sighting locations to accessibility of the 

 locations (Kuchel 1977, Wallen 1987, Diamond and Finnegan 1993, Cassirer and Groves 1991, 

 1994, Clarkson 1992, Ashley 1994). Specifically, boating has been shown to have a significant 

 negative correlation with numbers of ducks present in one area on a medium-sized stream 

 (Clarkson 1992, Hunt 1993). Observations in other areas tend to support this conclusion 

 (Cassirer and Groves 1991, Brady pers. comm. in Clarkson 1992) in this may not be the case in 

 very large streams (Smith 1996). Fishing and human presence has also been suggested as a cause 

 of disturbance with specific examples, but without statistical data analyses (Wallen 1987, 

 McEneaney 1994, Cassirer and Groves 1991). 



Wide-scale analyses have not yet been attempted nor have analyses on the effects of most specific 

 kinds and amounts of human activities except boating. Several specifics should be done to 

 address these questions. 



First, wide-scale data on Harlequin streams should be gathered including productivity, population 

 size, length of stream segments used during pair and brood seasons, categories and locations of 

 land ownership of the streams, hydrogeological properties of the streams, habitat of the streams, 

 and current human use of the stream (by roads, trails, structures, activity, etc.). A first step will 

 be to see what is available and what needs to be gathered in the field. Some such as population 

 size, and length of stream segments used is known for many streams, while others need 

 preliminary data gathering to determine what is available (hydrogeological properties, habitat of 

 the streams, and current human use). We can then randomly select unused and/or unknown 

 streams that fit physical parameters of used streams and compare them in respect to kind and 

 amounts of disturbance/accessibility. See Proposals 2 and 3. 



Second, responses to humans could be evaluated by recording initial responses to surveyors. This 

 would only give immediate, in sight response of birds which were seen; presumably some would 

 react prior to the surveyor seeing them and not be observed. Nor would it revel how much time 

 or distance the bird moved in reaction to the disturbance. A more precise but intrusive method 

 would be to use radiotelemetry on the birds. Radio-telemetry would also provide more accurate 

 data on use of habitat types and locations relative to human development/access points. See 

 Proposal 4. 



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