Behavior and Home Range of the Arctic Ground Squirrel


Meeting Abstract

P3.161  Tuesday, Jan. 6  Behavior and Home Range of the Arctic Ground Squirrel FENN, A.M.*; WRIGHT, A; RICHTER, M.M.; BUCK, C.L.; Colorado State University; University of Alaska Fairbanks; University of Alaska Anchorage amfenn@simla.colostate.edu

Behavior of free-living male arctic ground squirrels (Spermophilus parryii) (AGS) was observed north of the Alaskan Brooks Range during the summer months of July and early August in 2007 and 2008 to quantify aggressive, foraging and caching behavior. In 2008, home range (HR) boundaries and locations of afore mentioned behaviors were also observed. HR use expanded during early and mid July, centralizing around a burrow in late July and early August. Total HR of the males was smaller than expected. This difference was attributed to the rigid territories males defend and the limiting burrow space. While others have noted little to no aggression among males during July, our behavior observations and assessment of physical condition suggest aggression occurs consistently throughout July within areas of HR overlap. The intensity of the interactions increased following the second week of July around the time males began accumulating food caches. It has been noted that hibernators will undergo a period of hyperphagia to increase fat mass needed for hibernation. In the current study, foraging time increased from July to August, but decreased in proportion to time above ground correlating with increased time spent protecting a cache and engaging in aggressive interactions. The arctic poses unique constraints to AGS. A short active season results in a shortened breeding season as compared to more temperate zone hibernators and thus, males must accumulate a cache in the fall to allow them to end heterothermy and become reproductively active in early spring. We hypothesize that the presence of a cache and limited number of hibernacula account for the persistent territorial aggression observed in male AGS. These constraints also appear to drive the majority of HR and foraging behaviors.

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