The attraction of the known: the importance of spatial familiarity in habitat selection in wapiti Cervus elaphus

Abstract

Most studies of habitat selection by large herbivores focus on the resource availability and interactions with other species, but neglect the importance of an animal being familiar with an area due to past use. Yet, studies of the establishment and retention of territories, home ranges, birth sites, and feeding site choices in experimental settings have shown the importance of spatial familiarity at these scales. We used GPS locations of translocated wapiti Cervus elaphus, resource selection functions (RSF), and time-to-return to examine whether previous site use was important for selection of sites by wapiti in west-central Alberta. To construct RSFs, we used logistic regression that included spatial familiarity (presence of a previous GPS location within a 50-m radius) as well as estimates of herbaceous and shrub biomass, elevation, aspect, slope, and predation risk to wapiti from wolf predation, as dependent variables. We found that previous use had a strong positive relationship with subsequent site use, indicating that wapiti were not avoiding previously visited locations, as would be expected if memory of forage depletion (which we did not measure) determined response to familiar locations. Revisited sites were of higher quality, i.e. had more moderate terrain, higher forage, and lower predation risk, than sites that were not revisited, indicating that the selection of familiar locations was likely not the result of avoidance of unfamiliar locations. Finally, animals demonstrated preference for familiar locations that it had visited most recently, indicating that memory (which would decline with time) of higher site quality, rather than high quality alone, influenced selection for familiar locations. We conclude that spatial familiarity is important not only for large scale processes such as selection of home range and territory, but for smaller scale habitat selection and foraging as well.

Home sweet home: fitness consequences of site familiarity in female black-tailed deer

“…This supposition has led to an enduring belief among behavioral ecologists that familiarity with a physical space, or site familiarity, improves individual fitness (Baker 1978;Greenwood and Harvey 1982;Stamps 1995;Harwood et al 2003). Benefits associated with site familiarity have also been proposed as the mechanism underlying the widespread occurrence of site fidelity in multiple taxa (Switzer 1993;Wolf et al 2009). Many species expend great effort to return to previously occupied seasonal ranges, often migrating over large distances, and such fidelity to a particular location has been shown to enhance survival and reproductive success (Switzer 1993).…”

Building the bridge between animal movement and population dynamics

“…The importance of memory and previous experiences is starting to be explicitly considered in the analysis of movement data Wolf et al 2009), and in simulation models of foraging and habitat use (Barraquand et al 2009;Van Moorter et al 2009). Smouse et al (2010) provide a summary of the approaches used to include memory in movement models.…”

Foraging theory upscaled: the behavioural ecology of herbivore movement

“…For marine organisms, search strategies for locating feeding opportunities that are unpredictable in space have been emphasized (Bartumeus 2009;Reynolds & Rhodes 2009). For terrestrial herbivores, memory of the places where the most favourable resources are generally found at particular times plays a more important role (Bailey et al 1996;Van Moorter et al 2009;Wolf et al 2009). Intra-and interspecific competition among herbivores arises mainly through the depression of food resources rather than via direct interference with the uptake of this food.…”