LITERATURE CITED V ! 



American Ornithologists' Union. 1983. Check-list of North American birds, 6th edition. Allen 

 Press, Lawrence, Kans. 877 pp. 



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

 Park, 1874-1992. Unpubl. Report, Glacier Natl. Park, West Glacier, Mont. 19 pp. 



Ashley, J. 1994a. 1992-93 Harlequin duck monitoring and inventory results in Glacier National 

 Park, Montana. Unpubl. Report, Glacier Natl Park, West Glacier, Montana. 57 pp. 



Ashley, J. 1 994b. Progress report: Harlequin duck inventory and monitoring in Glacier National 

 Park, Montana. Unpubl. Report, Glacier Natl Park, West Glacier, Montana. 14 pp. 



Bellrose, F. C. 1976. Ducks, geese and swans of North America. Stackpole Books, Harrisburg, 

 Perm. 540 pp. '> v. .. 



Bengtson, S.A. 1966. Field studies on the harlequin duck in Iceland. Wildfowl Trust Aim. Rep. 

 17:79-94. 



Bengtson, S!A. 1972. Breeding ecology of the harlequin duck Histrionicus histrionicus (L.) in 

 Iceland. Omis Scand. 3:1-19. 



Bengtson, S.A. and S. Ulfstrand. 1971. Food resources and breeding frequency of the harlequin 

 duck, Histrionicus histrionicus, in Iceland. Oikos 22:235-239. ' ■ ■' 



Carlson, J. C. 1990. Results of harlequin duck {Histrionicus histrionicus) surveys in 1990 on the 

 Flathead National Forest, Montana. Mont. Nat. Heritage Prog., Helena. 32 pp. 



Cassirer, E. F., A. Breault, P. Clarkson, D.L. Center, R. I. Goudie, B. Hunt, S. C. Latta, G. H. 

 Mittelhauser, M. McCollough, G. Schirato, and R. L. Wallen. 1993. Status of harlequin ducks 

 {Histrionicus histrionicus) in North America. Report of the Harlequin Duck Working Group. 

 83 pp. 



Cassirer, E. F. and C. R. Groves. 1989. Breeding ecology of harlequin ducks {Histrionicus "^ 

 histrionicus) on the Kaniksu National Forest, Idaho. Idaho Dept. Fish Game, Nongame 

 Endangered Wildl. Prog. 48 pp. 



Cassirer, E. F. and C. R. Groves. 1990. Distribution, habitat use, and status of harlequin ducks in 

 northern Idaho, 1990. Idaho Dept. Fish Game, Nongame Endangered Wildl. Prog. 54 pp. 



Cassirer, E. F. and C. R. Groves. 1991. Harlequin duck ecology in Idaho: 1987-1990. Idaho 

 Dept. Fish Game, Nongame Endangered Wildl. Prog. 93 pp. 



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