Diurnal activity patterns within female herds of isard around parturition time

Abstract

We compared diurnal activity patterns of isards (Rupicapra pyrenaica) within female herds around the time of parturition in a Pyrenean reserve. From mid-April to mid-May, i.e., at the end of the gestation period, adult females spent significantly more time foraging (76 vs. 65%) and less time resting than yearlings did. From mid-June to mid-July, after the birth of kids, adult females and yearlings had exactly the same time budget (62% for foraging) and the same activity pattern, with a well-marked resting phase at midday. Analysis of data at 15-min intervals indicated synchronism in activity when animals leave the area by crossing the crest line, or when arriving at their foraging or resting phases. During the 2 first months of their life, kids had a polyphasic diurnal activity pattern characterized by four distinct foraging phases 4 h apart, and three peaks in resting activity between midday and evening. Nevertheless, some behavioural and physiological mechanisms permitted kids to synchronize their activity with that of other herd members.