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dc.contributor.supervisor Sealy, Spencer (Advisor) en
dc.contributor.author Wishart, Richard A.
dc.date.accessioned 1983-03-31T16:52:17Z
dc.date.available 1983-03-31T16:52:17Z
dc.date.issued 1983-03-31T16:52:17Z
dc.identifier.uri http://hdl.handle.net/1993/4404
dc.description.abstract The behavioral ecology of the American Wigeon (Anas americana) was studied over its annual cycle in western Canada between 1974 and 1978. The objective of this work was to examine the cross-seasonal interactions of the biology and behavior of the wigeon as they underlie the evolution of its mating system. The wigeon was more herbivorous than any other dabbling duck studied so far and spent a considerable amount of time feeding in upland habitats. Vegetation was important in the diet year round but particularly from late summer through the winter. Plant seeds were a rich source of protein and carbohydrate early in the spring. During breeding stages animal foods were selected by wigeons, particularly females. Wigeons usually did not feed on small crustaceans and gastropods but selected larger aquatic insect foods. Relative to other Anas soecies, the wigeon has a goose-like bill whose structure facilitates feeding on upland and aquatic vegetation. With the evolution of this specialization, efficient surface-straining of small foods has been sacrificed. To increase food digestibility, wigeons altered gizzard grit composition and organ sizes. Through these mechanisms I have demonstrated how wigeons have been able to increase the efficiency of digestion. en
dc.format.extent 128855385 bytes
dc.format.mimetype application/pdf
dc.language.iso en_US
dc.rights info:eu-repo/semantics/openAccess
dc.subject American Wigeon en
dc.subject wigeons en
dc.subject behavioral ecology en
dc.subject dabbling duck en
dc.subject Anas americana en
dc.subject wigeon breeding stages en
dc.subject wigeon feeding habits en
dc.title The behavioral ecology of the American Wigeon (Anas americana) over its annual cycle en
dc.type info:eu-repo/semantics/doctoralThesis
dc.degree.discipline Zoology en
dc.contributor.examiningcommittee Not available. en
dc.degree.level Doctor of Philosophy (Ph.D.) en
dc.description.note Spring 1983 en


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