Northern Prairie Wildlife Research Center
Lack of Reproduction in Muskoxen and
Arctic Hares Caused by Early Winter?
Because of the remoteness and inaccessibility of Canada's High Arctic islands,
few details are known about their wildlife populations and the factors that
affect these populations. For example, there appear to be only three publications
touching on arctic hare ecology (Parker, 1977; Klein and Bay, 1995; and Schaefer
et al., 1996) and, although muskoxen have been well studied, "we have no idea
why periodic declines occur" (Theberge, 1972:28). Thomas et al. (1981) saw extreme
winter weather as a logical cause of muskox declines, and Gunn et al. (1989)
proposed a hypothesis involving above-average snow depths in spring. Excessive
snowfall and ice crust have also been blamed for muskox declines, yet the effects
of these conditions vary throughout muskox range (summarized by Forchhammer
and Boertmann, 1993).
Densities of arctic mammals tend to be lower than those of mammals inhabiting
lower latitudes, so population and productivity declines are more serious
and thus more noteworthy. This article reports evidence of such a decline
in muskox and arctic hare populations on part of Ellesmere Island during winter
1997-1998, when neither ice crusts nor excessively deep snow prevailed. An
alternative weather-based hypothesis is offered.
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