The behavioural ecology of dingoes in north-western Australia. V. Population dynamics and variation in the soical system

Abstract

Between 1975 and 1984, 105 radio-collared dingoes, Canis familiaris dingo, were tracked and observed from aircraft on the Fortescue River in Western Australia. The majority of dingoes were members of 18 territorial packs, including four pairs. Five packs were monitored for more than three years. Most bitches became pregnant, including those 9-10 months old, although not all litters were raised. Packs raised an average of 1.1 litters per year. Instances of packs raising the litters of two bitches in a year were recorded. The area (up to 400km*2) was covered initially (1975-78) by a mosaic of stable pack territories. Little emigration occurred and population density rose to a peak of 22.2 dingoes per 100km*2 in 1978 due to an increase in pack size. Perturbations to the social system, including disintegration of some packs, an increase in emigration, shifts of pack territories and contraction of territories into the most favoured areas, coincided with high population density and a reduced food supply. After aerial baiting in 1980 killed all the dingoes from the study site, immigrants from surrounding areas established a new population. The increase in density was moderated by the formation of new pairs or packs that occupied surrounding vacant areas. The dispersal strategy of pack members was a major factor affecting the population density of dingoes in the study area.