Interactions between adult female and juvenile Anteclunus stuartii ( Marsupialia: Dasyuridae) at the time of juvenile dispersal.

Abstract

Juvenile male Antechinus stuartii disperse from the natal site soon after weaning when their mothers are present, but may be philopatric when mothers are missing. These males join other nesting groups which may include adult females. Juvenile males may thus be caused to emigrate by their mothers. We tested the hypothesis that parous females exhibit more aggression towards their newly-weaned sons than towards other juveniles at the time of dispersal. Encounters between females and juveniles were observed in a test arena in the fi eld. Females were not more aggressive towards sons. Encounters between mothers and offspring involved more contact and investigation than those between adult females and alien young, indicating kin recognition in the test situation. Proximate mechanisms other than maternal aggression may cause male-biased juvenile dispersal.