5) How and why do productivity and survival change over time and different areas, and what are 

 the relative impacts of these changes on populations? 



Long term studies are needed to determine population parameters for incorporation into 

 population models (with information from movements on the breeding and wintering grounds). 

 Needed population parameters include: productivity; age-related survival; recruitment; age(s) at 

 first breeding and/or successful breeding; age(s) last breeding; life expectancy; and causes and 

 timing of mortality. This information can only be provided via long-term studies involving 

 marked birds on both the breeding and wintering areas. We are currently in an optimum position 

 to complete studies needed on the breeding grounds, with 4 years of data on the Montana 

 breeding population. Combined with the continued marking and study of coastal populations by 

 Alaska, Washington, Oregon, and British Columbia, many of these parameters may be known by 

 the end of 1997. 



The most difficult question to be answered involves the causes of mortality, which is not 

 tractable given current technology. If and when small, long range mortality transmitters are 

 available for ducks, this topic should be pursued. 



6) What are the characteristics of Harlequin Duck migration? How well defined are migratory 

 staging areas and migration corridors? 



This question may not be tractable given current technology. If and when small, long 

 range mortality transmitters are available for ducks, this topic should be pursued. Some answers 

 may come from large scale marking of individuals, and perhaps by relocating radioed birds. 



REFERENCES 



Alford, C. E. 1920. Some notes on the harlequin duck. British Birds 14:14-17. 



American Ornithologists' Union. 1983. Check-list of North American Birds, 6th edition. Allen Press, Inc., Lawrence, 

 Kansas. 877 pp. 



Ashley, J. 1992. A summary of documented harlequin duck observations in Glacier National Park, 1874-1992. 

 Unpublished draft report, 18 pp. plus maps. 



Ashley, J. 1994a. 1992-93 harlequin duck monitoring and inventory in Glacier National Park, Montana. Unpublished 

 report. Div. Res. Manage., Glacier Natl. Park, Montana. 57 pp. 



Ashley, J. 1994b. Progress report: harlequin duck inventory and monitoring in Glacier National Park, Montana. 

 Unpublished report. Div. Res. Manage., Glacier Natl. Park, Montana. 14 pp. 



Ashley, J. 1994c. Status of Harlequin ducks in Glacier National Park, Montana. P. 2 in: Proc. 2nd ann. Harlequin duck 

 symposium, March 13-15, 1994. Harlequin Duck Working Group. 22 pp. plus appendices. 



Ashley, J. 1995. Harlequin duck surveys and tracking in Glacier National Park, Montana. Unpublished report. Div. 

 Natural Resources, Glacier National Park, West Glacier, Montana. 41 pp. 



Atkinson, E. C. and M. L. Atkinson. 1990. Distribution and status of harlequin ducks {Histrionicus hislrionicus) on the 

 Targhee National Forest. Idaho Dept. of Fish and Game, Nongame and Endangered Wildl. Prog. 25 pp. 



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