Population dynamics of white-winged scoters

David G. Krementz; P.W. Brown; F.P. Kehoe; C.S. Houston

doi:10.2307/3802431

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Population dynamics of white-winged scoters

David G. Krementz·P.W. Brown·F.P. Kehoe·C.S. Houston

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Abstract

A significant ( P < 0.01) decline between 1961 and 1993 in ratio of harvested young per adult in the Atlantic Flyway (age ration) of white-winged scoters ( Melanitta fusca ) led us to examine annual survival rates and harvest of this species. Compared to waterfowl with similar life histories, black scoters ( M. nigra ) and surf scoters ( M. perspicillata ), the decline in age ratios of white-winged scoter age ratios was not significantly different ( P = 0.11). Adult females banded at Redberry Lake, Saskatchewan that winter along both coasts, had high annual survival rates (0.773 ± 0.0176 [SE]). High harvest in the Atlantic Flyway was not followed by an increase in production (age ratios) the following year or 2, i.e., there was no short-term rebound in recruitment by the population. Harvest of white-winged scoters in the Atlantic Flyway was explained by the age ratio in the fall flight and by hunter effort.

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Journal of Wildlife Management Article

Source-reported bounding extent: 36.632804273458504° to 45.30186587969985° latitude; -78.156631094868° to -71.13897441301259° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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David G. Krementz, P.W. Brown, F.P. Kehoe, C.S. Houston. 1997. Population dynamics of white-winged scoters. https://doi.org/10.2307/3802431

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