Behaviours of collared and white-lipped peccaries [Tayassu tajacu and T.pecari] in relation to sexual receptivity of the female

Changes in behaviours of the two peccary species, Tayassu tajacu Linnaeus, 1758 and T. pecari Link, 1795 between non-receptive and receptive periods were followed by presenting females to males daily for 15 minutes. In T. tajacu, the rank order of behaviours, similar in both sexes during the non-receptive period, differs during receptivity. Contact behaviours decrease in males, whereas sexual ones progress. The same tendency appears in females. Inhibited bites replace markings of partner as the most common behaviour in both sexes. In T. pecari, the rank order of behaviours always differs between sexes. When females become receptive, the differences from the non-receptive period are neither numerous nor significant. The most common behaviour of males, previously markings of partner, becomes mounts, whereas in females agonistic behaviours reinforce their dominance. In this species, the only behaviours that increase are those leading directly to copulation or those of an agonistic nature. In both species, females show more agonistic behaviours than males (mainly inhibited bites in T. tajacu, truly aggressive ones in T. pecari). When females are receptive, males of T. pecari become less active, contrary to T. tajacu where both sexes double their activity. In T. tajacu, most behaviours vary significantly in relation to the progesterone level, contrary to the other species. These pecularities appear correlated to herd composition and organisation.