Density distributions and habitat associations of red kangaroos, Macropus rufus, and western grey kangaroos, M. fuliginosus

Abstract

Density distributions of red and western grey kangaroos in the South Australian pastoral zone were determined for the period 1978-86. The habitat associations of these kangaroos were analysed using the densities on half-degree blocks, and information on landform and soil type, land use and degradation, vegetation, and climate. Red kangaroos were found throughout the pastoral zone, the highest densities being in the north-east. Western grey kangaroos were restricted to the southern parts of the pastoral zone. Higher densities of red kangaroos were associated with pastoral land use, with brown calcareous and red duplex soils, and with areas dominated by low bluebush shrublands. They were not particularly closely associated with areas dominated by mulga. Habitat associations of red kangaroos were different in drought years compared to non-drought years. Changes in density distribution during drought appears to have been due to the patchiness of rainfall. The relative effect of the drought was greatest in the northern part of the pastoral zone. Outside this effect, recent rainfall was found to be of only secondary importance to the overall density distribution of red kangaroos. Climatic factors appeared to be the major determinants of the density distribution of western grey kangaroos. Low evaporation and relatively high rainfall characterised areas with high densities of western grey kangaroos. As was the case with red kangaroos, habitat heterogeneity appeared to be an important requirement of western grey kangaroos. Also, habitat associations were different in drought and non-drought years. Despite this, as was the case with red kangaroos, recent rainfall was only of secondary importance to the overall distribution of western grey kangaroos.

Spatial patterns of kangaroo density across the South Australian pastoral zone over 26 years: aggregation during drought and suggestions of long distance movement

“…The results show that the broad pattern of distribution of both red and western grey kangaroos in the SAPZ was relatively stable over the study period. High densities of red kangaroos were recorded consistently in the north‐east of the SAPZ, an area with a mosaic of soil and vegetation types, but dominated in general by low bluebush shrublands and calcareous soils and where sheep are grazed at a relatively high density (Cairns, Pople & Grigg 1991). Western greys are restricted to the less arid parts of the study area and densities were consistently high in the south‐west.…”

“…Priddel 1988). Short time‐frames also have constrained interpretation of data from most previous studies and, with the exception of Cairns, Pople & Grigg (1991), descriptions of broad‐scale kangaroo distribution have typically covered only 1–3 years, limiting the generality of the results. Distribution data spanning long time‐scales (decades rather than years) also allows assessment of hypotheses specific to temporal variation.…”

“…This paper analyses the long‐term spatial variations in red and western grey kangaroo distribution for the South Australian pastoral zone. It extends the analysis of Cairns, Pople & Grigg (1991) by using a considerably longer time‐series and geostatistical methods to explore patterns of distribution and annual changes in the dispersion of kangaroos at a finer scale. The resulting spatial and temporal patterns will allow kangaroo and land managers to allocate harvest quotas and interpret variation in harvest offtake more effectively.…”

Large-Herbivore Distribution and Abundance: Intra- And Interspecific Niche Variation in the Tropics

“…As a comparison, in southern Australia, eastern grey kangaroos and common wallaroos have been recorded at densities above 30 individuals/km 2 (Southwell et al 1999). Likewise, red kangaroos (Macropus rufus) have been found at similar densities in the arid southern rangelands of Australia (Caughley et al 1977, Cairns et al 1991. This discrepancy in the typical density of large macropods in tropical vs. temperate and arid regions is of biological and conservation significance.…”

Frequency and causes of kangaroo - vehicle collisions on an Australian outback highway

“…Kangaroos in arid and semi-arid regions do not have particular breeding times but generally breed throughout the year (Newsome 1965;Russell and Richardson 1971;Norbury et al 1988;Cairns et al 1991). Hence seasonal breeding activity or dispersal of juveniles cannot explain seasonal differences in the frequency of road-kills in kangaroos, unlike in other fauna such as deer (Allen and McCullough 1976;Hubbard et al 2000), ungulates in general (Groot Bruinderink and Hazebroek 1996), prairie nesting ducks (Sargeant 1981), and the European badger (Davies et al 1987).…”