Common Dynamic Structure of Canada Lynx Populations Within Three Climatic Regions

University of Toronto, Toronto, Ontario, Canada
Science (Impact Factor: 33.61). 09/1999; 285(5430):1071-3. DOI: 10.1126/science.285.5430.1071
Source: PubMed


Across the boreal forest of Canada, lynx populations undergo regular density cycles. Analysis of 21 time series from 1821
onward demonstrated structural similarity in these cycles within large regions of Canada. The observed population dynamics
are consistent with a regional structure caused by climatic features, resulting in a grouping of lynx population dynamics
into three types (corresponding to three climatic-based geographic regions): Pacific-maritime, Continental, and Atlantic-maritime.
A possible link with the North Atlantic Oscillation is suggested.

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    • "In contrast, Hone et al. (2011) considered the mechanism for the effect of the NAO on the lynx numerical response was not known clearly but may be via demographic rates. For grey wolves living on Isle Royale, Michigan USA, hunting success was significantly increased during winters of deep snow as a result of the increased vulnerability of their prey species (moose; Post and Stenseth 1998, Post et al. 1999). Coyote predation on white-tailed deer was found to increase sharply, and continue to increase disproportionately relative to the availability of snowshoe hares, as deer became increasingly vulnerable with increased snow depth (Patterson et al. 1998). "
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    • "differential snow conditions (Hurrell, 1996). Given the ecological importance of snow conditions for temperate species (Telfer & Kelsall, 1984; Campbell et al., 2005), there is strong potential for these differential conditions to cause increased genetic structure for the terrestrial animals across this region (Stenseth, 1999; Rueness et al., 2003). This appears to be the case for the Canada lynx (Lynx canadensis), whose range extends across the northern half of North America and across the PNO-NAO climate boundary. "
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    • "Meteorological variations can also influence small mammal population dynamics by affecting primary productivity, leading to local declines in severe winters or high densities after warm and wet winters (Ottersen et al., 2001; Stenseth et al., 2002b). Such variations in the abundances of small mammals have been related to the dietary responses and population dynamics of several predators (Stenseth et al., 1999; Malo et al., 2004; Raoul et al., 2010). Some parasites with a complex life-cycle are characterised by a free-living stage that disseminates into the environment (e.g., soil or water), and environmental factors can modulate parasite survival within the environment (Mouritsen and Poulin, 2003). "
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