Evidence for exploration behaviour in young roe deer (Capreolus capreolus) prior to dispersal

Abstract

Natal dispersal is a three-phase process: the decision to leave the natal range, the search phase and finally the settlement phase. Not much is known about the search phase in large herbivores. We quantified the search behaviour of young roe deer from two contrasting populations, using different measures: search area, search rate, search intensity and philopatry of the search. A Principal Component Analysis showed that most measures were highly correlated. Comparing the first axis from this analysis between adult and young roe deer from the two different populations while controlling for habitat quality, we found that the young occupied a larger area, ranged on average farther away and performed more excursions than adults, regardless of their sex. These findings support the hypothesis that young roe deer explore their environment before definitively leaving their natal home range and settling in their adult range. key words: Ungulates; home range; search behaviour; habitat use.

The Effect of Capture on Ranging Behaviour and Activity of the European Roe Deer Capreolus capreolus

“…Adult roe deer are considered to have a high degree of spatial stability whereas yearlings are generally more mobile, using a larger daily and seasonal range (Hewison et al 1998). Yearlings may enlarge their home range in order to explore new habitats before settling within a defined home range or territory (Van Moorter et al 2008), or alternatively their higher mobility may be due in part to the fact that they suffer more aggressive interactions than adults (e.g. Wahlstro¨m 1994).…”

No evidence of juvenile body mass affecting dispersal in male red deer

“…Many large herbivore populations, such as the red deer in our study, occupy areas of continuous habitat cover where migration corridors often consist of the normal feeding habitat. Young individuals show exploratory behaviour before dispersing (Van Moorter et al ., 2008) and the energy cost of exploration and subsequent dispersal may be relatively small and affordable even for low‐quality individuals. For populations with very low rates of natural predation, large variation in survival between philopatric and dispersing individuals is not expected (snow shoe hares Lepus americanus ; Gillis & Krebs, 2000).…”

Condition‐dependent natal dispersal in a large herbivore: heavier animals show a greater propensity to disperse and travel further

“…The timing of dispersal is thus highly synchronised (Wahlstrom & Liberg ; Linnell, Wahlstrom & Gaillard ; Van Moorter et al . ) so that the dispersal status of juveniles can be reliably determined by the end of July. Of the 79 juveniles captured and for which data were recovered, only those 60 individuals that were monitored from their capture in winter to at least the following August 1st and had more than 50 locations during the summer period were included in the analyses.…”