Geographic variation in winter adaptations of snowshoe hares (Lepus americanus)

Canadian Journal of Zoology
By: , and 



Understanding adaptations of nonhibernating northern endotherms to cope with extreme cold is important because climate-induced changes in winter temperatures and snow cover are predicted to impact these species the most. We compared winter pelage characteristics and heat production of snowshoe hares (Lepus americanus Erxleben, 1777) on the southern edge of their range, in Pennsylvania (USA), to a northern population, in the Yukon (Canada), to investigate how hares might respond to changing environmental conditions. We also investigated how hares in Pennsylvania altered movement rates and resting spot selection to cope with variable winter temperatures. Hares from Pennsylvania had shorter, less dense, and less white winter coats than their northern counterparts, suggesting lower coat insulation. Hares in the southern population had lower pelage temperatures, indicating that they produced less heat than those in the northern population. In addition, hares in Pennsylvania did not select for resting spots that offered thermal advantages, but selected locations offering visual obstruction from predators. Movement rates were associated with ambient temperature, with the smallest movements occurring at the lower and upper range of observed ambient temperatures. Our results indicate that snowshoe hares may be able to adapt to future climate conditions via changes in pelage characteristics, metabolism, and behavior.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Geographic variation in winter adaptations of snowshoe hares (Lepus americanus)
Series title Canadian Journal of Zoology
DOI 10.1139/cjz-2016-0165
Volume 95
Issue 8
Year Published 2017
Language English
Publisher NRC Research Press
Contributing office(s) Coop Res Unit Leetown
Description 7 p.
First page 539
Last page 545