Response to intruders in female rabbit colonies is related to sex of intruder and rank of residents.

Behavioural reactions to unfamiliar conspecifics of both sexes were studied in female domestic rabbits, living in stable unisexual groups. Intrusion caused an abrupt increase in the frequency of social investigation and agonistic behaviours directed to both intruders and group-mates. Reactions depended on the rank of resident females and the sex of the intruder, and were generally more marked in the presence of the male than the female intruder. Dominant and sub-dominant females investigated the male more than the female intruder; the opposite held for subordinate females. In the presence of the female intruder, only dominant and subdominant females were aggressive towards the intruder and group-mates. In the presence of the male intruder, aggression was directed to the intruder and group-mates by dominant females only. They tended to frequently attack sub-dominants, which in turn fled away from them more often than they did from other group-mates.