Thermoregulation as a limit to habitat use in alpine marmots (Marmota marmota)

Abstract

The body temperature (T ) of free-living alpine marmots rose with activity; the higher the effective environmental temperature (T), the higher the rise. Maximum T of 40° C was reached at the time of greatest activity in late afternoon or evening. The activity pattern was strongly influenced by the microclimate. Up to an Tof 25° C the animals spent more time above ground and were more active the higher T was, but above 25° C this trend was reversed, and the animals withdrew increasingly into their burrows. On warm days the activity pattern was therefore bimodal and above ground presence was reduced, in contrast to cool days. Hence behavioural thermoregulation limits the available time for above ground activity on days with high Tin this strictly diurnal species. We suggest that the alpine marmots' preference for south oriented slopes is due to the better conditions for hibernation there, the microclimate during summer is more favourable on northerly slopes. Thermoregulatory constraints could also keep alpine marmots away from lower elevations.

Socially mediated effects of climate change decrease survival of hibernating Alpine marmots

“…). By constraining the ability of Alpine marmots to thermoregulate efficiently, high temperatures reduce the time window in which they can forage in summer (Türk & Arnold ). In addition, high summer temperatures lead to an earlier senescence of the vegetation, and thus forage of poor nutritional quality (Pettorelli et al .…”

Thermoregulatory constraints on the microhabitat use by Cricetid Rodents in Central Chile

“…However, Ammospermophilus leucurus in the Deep Canyon Desert of California is thermically and energetically constrained in the use of microhabitats (Chappel and Bartholomew 1981, a, b); the same situation is reported by Turk and Arnold (1988) for Marmota marmota. Similarly, thermal and wind conditions influence the use of thermically protected microhabitat of Carduelis iritis (Buttemer 1985) and Phainopepla nitens (Walseberg 1986).…”

Seasonal Patterns of Body Temperature Daily Rhythms in Group-Living Cape Ground Squirrels Xerus inauris

“…Consequently, evaporative cooling is often accompanied by behavioral and physiological mechanisms to dissipate heat such as the use of a thermal refuge or substrate [50] or heterothermy [13], [51]–[53]. In the current study, Cape ground squirrels were exposed to a wide seasonal and daily range of T a and the T b mesor of all individuals increased significantly as the season progressed.…”