Temperate species occupying habitats at the northern limit of their geographical distribution are limited by weather and climatic conditions. Such conditions often directly affect population dynamics, and thus, influence shifts in distribution via changes in demographic parameters. We examined this question by following three distinct populations of wild turkeys inhabiting areas exposed to a gradient of meteorological conditions at the northern limit of the species distribution. Four years of radio‐telemetry on 181 birds and monitoring of 95 nests revealed that population demographics of wild turkeys were influenced by snow depth, winter temperature and summer rainfall. During winter, survival of turkeys decreased drastically when snow depth remained >30 cm for >10 days and also decreased as temperatures got colder. In the spring, snow persistence delayed nest initiation, whereas nest survival was negatively affected by rainfall. Our findings show that the effects of critical meteorological factors such as snow and temperature can be compounded when both reach the limit of a species tolerance simultaneously.

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In Quebec, Canada, harvest of bobcats (Lynx rufus) started to decline in 1985 and by 1991, harvest seasons were closed due to concerns of a perceived population decline. Since the closing of harvest season in 1991, the average temperature has increased, snow quantity has decreased, and important changes in agriculture and forest management have occurred.

Lynx canadensis Kerr, 1792, commonly called the Canada lynx, is a medium size felid and is the second largest of the four species in the genus Lynx. It is distributed throughout the boreal forest of most of Canada and Alaska and across portions of the northern United States. It prefers dense, regenerating coniferous forests with moderate canopy and understory cover. L. canadensis is a snowshoe hare specialist, and its ecology, morphology, and behavior closely reflect that of its main prey. It is listed as "Least Concern" by the International Union for Conservation of Nature and Natural Resources, is on Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora, and its population size trend is considered stable. However, the status of United States subpopulations, being largely peripheral to the Canadian population, is more tenuous and the species is protected.

We examined the mass, foot area and foot load (mass/surface area) of Fishers (Carnivora: Mustelidae: Martes pennanti) captured during the 2006-2007 commercial fur season in southern Quebec, Canada. Body mass of males (mean = 4.7 kg ± 0.5, n = 37) was significantly larger than that of females (mean = 2.4 kg ± 0.2, n = 40). Similarly, the size of male feet (mean area = 130.5 cm2 ± 10.9, n = 37) was significantly larger than that of females (mean = 95.2 cm2 ± 7.6 SE, n = 40). The resulting footload of males (36.2 g/cm2 ± 6.1, n = 37) was 43% larger than that of females (25.3 g/cm2 ± 2.3, n = 40). These results may help explain the differential behaviour and niche partitioning in this mustelid carnivore.