Animals are constantly submitted to internal and external constraints. The processes that regulate the acquisition and allocation of resources among the competing demands of growth, survival and reproduction occupy a central place in evolutionary ecology (Candolin 1998; Ghalambor & Martin 2001; Ihara 2002). Many theoretical, empirical and experimental studies suggest that most behavioural decisions are the expression of such adaptive trade-offs (Houston & McNamara 1999; Kemp et al. 2006). For example, an individual cannot undertake simultaneously antagonistic activities such as foraging and ritual combats during reproduction. Therefore, collecting information on activity budgets of wild animals, especially the temporal organization of contrasted behaviours, is of prime importance to understand the processes of acquisition and allocation of resources in relation to physiological status and environmental conditions....
