Surveys of the distribution and density of kangaroos in the pastoral zone of South Australia, and their bearing on the feasibility of aerial survey in large and remote areas

Abstract

Kangaroos were censused from the air in 1978, and again in 1979, within the pastoral zone of South Australia, an area of 242,000 km2, three and a half times the size of Tasmania. Logistical problems were minimal despite the remoteness of much of the area, but more than half the time in the air was spent in flying to and between transects. Red kangaroos occurred throughout the zone at the mean density of 4.62 km–2. Western grey kangaroos averaged a density of 1.22 km–2 over the whole area but were restricted to its southern half. Although the area was sampled at the low intensity of 1.3% the estimates were reasonably precise, that for red kangaroos having coefficient of variation of 7% at each survey, that for grey kangaroos, 13%. Estimated numbers did not differ significantly between years. Maps of density and distribution are given for each species. The cost of such a survey is around 6c per km2 for each 1% of sampling intensity.