Spatio-temporal interactions among male and female long-nosed potoroos, Potorous tridactylus (Marsupialia : Macropodoidea): mating system implications

Abstract

This study investigated the mating system of the long-nosed potoroo, Potorous tridactylus, by examining temporal associations between individuals, and patterns of home-range overlap. Six adult females and five adult males were radio-tracked at intervals throughout the 24-h day from December 1996 to March 1997 in south-western Victoria. Home ranges of individuals overlapped with multiple members of each sex; however, intrasexual overlap was significantly lower than intersexual overlap. When data from consecutive radio-tracking sessions were examined, the locations of resting or ‘squat’ areas were identified. These were almost entirely intrasexually exclusive. Male home ranges overlapped the squat areas of one or more females; however, males did not regularly associate with every female whose squat area they overlapped. In three of four cases, pairs of a male and a female associated regularly and spent a greater proportion of time in close proximity to each other than would be expected if they were moving at random. In the past it has been assumed that males monitor the sexual status of females while they rest in squats. If this is the case, the mating system of long-nosed potoroos will be largely dictated by the number of female squat areas that a male is able to regularly monitor within his home range.