Do kangaroos exhibit water-focused grazing patterns in arid New South Wales? A case study in Sturt National Park.

Abstract

The density of kangaroos (Macropus spp.) within 5 km of current and former artificial watering points in Sturt National Park (NSW) was studied over a two-year period using the line transect method. Kangaroo densities were not significantly related to water proximity and did not significantly differ between open and closed watering points. Infrared sensors detected and counted kangaroo movements to and from artificial watering points and these were positively correlated with temperature. However, line transect counts did not reveal a shift in kangaroo distributions to water-proximate areas in warmer seasons. The results suggest that kangaroos travel to drink and then return to relatively stable home ranges that take advantage of sites offering the best grazing and resting opportunities. Vegetation surveys, using a wheel point device, revealed that the biomass of Atriplex spp. decreased significantly with increased proximity to artificial watering points, but the biomass of Poaceae spp. and numerous forbs did not. Vegetative diversity was unrelated to water proximity. Low vegetation biomass near artificial watering points in Sturt National Park may be more correctly attributed to the effects from past sheep-grazing pressure, than to any current grazing pressure. The implications of artificial watering point closure on conservation values and nature-based tourism are discussed.