Canada

The spacing and activity patterns of the small stoats living in southern Quebec, Canada, were observed by Robitaille and Raymond (1995), by live trapping stoats on farmland, predominantly hayfields (ca. 40%), cornfields (ca. 25%), pasture (ca. 15%), and woodlots (ca. 10%), from 1978 through 1980. The number of resident males was smaller than the number of transients each year, but the reverse was true for females, and more females overwintered than males. Nonetheless, residency times for females (mean = 157 days) exceeded those for males (82 days), with huge variation in both. One juvenile male lived on the study site for only 28 days, while one female was there for at least 443 days (almost 1 year and 3 months).

During the breeding season, males traveled farther between captures than females, but when the search for females was over, the travel distances for males decreased. By contrast, the period after breeding was the time that travel distances increased for females, as they took up the task of hunting for a whole family. Home ranges of11 live-trapped males averaged larger (20 ha) than those of 12 females (5 ha) and home ranges overlapped only between the sexes.

The rapid improvement in radio-tracking technology through the 1990s has produced many new data on home ranges (Table 8.1), although stoats are still difficult to work on and samples are sometimes small. Samson and Raymond (1995) radio tracked six female and five male stoats in summer 1988, following a male and a female across 35.3 ha and 15.6 ha, respectively. The stoats moved at speeds from 0.5 to over 23 m per minute, and traveled on average just under 500 m daily. As might be expected, they used the available habitats in ways that both favored good hunting and also ensured protection from larger predators. For example, an adult female preferred to use brush piles within a clearcut, while a juvenile male used the edges of a stream and many trails within a conifer plantation. Prey densities were high during the study, and the very small stoats of Quebec are more effective rodent hunters than their larger European cousins (Chapter 5) (Samson & Raymond 1995).

Lisgo (1999) studied stoats in the mixed boreal forest of east-central Alberta, in an area including black spruce, aspen, larch, and recently logged clearcuts piled with slash and overgrown with weeds. During most seasons except deep winter, the average home ranges of four radio-collared male stoats was 150 ha, and of four females, 80 ha, but they used the habitats differently. Females appeared to prefer the logged areas and avoided the other dominant habitats, while males avoided the logged areas and aspen and preferred the less extensive black spruce, larch, and birch and scrub habitats. Unfortunately, Lisgo did not estimate the amount of time the stoats spent in each habitat, only the relative proportions of different habitats in each home range area, which does not tell us how important each habitat type was to the stoats. Slash piles in logged areas supported high populations of small mammals, however, and the female stoats with radio collars often hunted there, consistent with Lisgo's analyses of habitat preferences.

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