Cattle removal in arid Australia benefits kangaroos in high quality habitat but does not affect camels

Abstract

Removing cattle as a management tool to conserve biodiversity may not necessarily alter grazing impacts on vegetation if other introduced or native herbivores move in and replace the cattle after removal. This study investigated whether there was a difference in the abundance of native red kangaroos (Osphranter (Macropus) rufus) and introduced feral camels (Camelus dromedarius) on arid rangelands where cattle had been recently removed compared with where cattle remained. Activity was measured by clearing and weighing dung, and by counting animal sightings. Kangaroos were encountered more frequently in high quality habitat (gidgee woodland) where cattle had been recently removed. However, kangaroo dung in newly cattle-free areas comprised only ~1.5% of the weight of cattle dung in this habitat where cattle still grazed, indicating no grazing compensation by the native herbivore. Camels showed no clear preference for particular habitat types but used dune tops usually avoided by kangaroos and cattle. There was no indication of camels using habitats differently in areas where cattle were removed. Camel dung collected across all habitats comprised less than a tenth the weight of cattle dung, but almost five times as much as kangaroo dung. As cattle removal had occurred relatively recently, further monitoring is needed to determine its impact over longer periods, especially through low and high rainfall cycles. Methods to improve the monitoring of large herbivores in the presence and absence of livestock and to assess whether anticipated conservation goals are achieved are discussed.