Home range and spatial organization of the rock-dwelling carnivorous marsupial, 'Pseudantechinus macdonnellensis'

Abstract

We studied home-range size, range length and spatial organisation of fat-tailed false antechinus, 'Pseudantechinus macdonnellensis', at Ormiston Creek, central Australia. Animals were tracked using transmitters implanted into the body cavity. Mean home-range size was 0.76 ha based on the minimum convex polygon (MCP) method and 1.14 ha based on the fixed kernel contour. Mean maximum range length was 148.83 m. Males occupied larger home-range areas than females (MCP: 0.98 v. 0.31 ha, 95% fixed kernel: 1.50 v. 0.43 ha) and also had greater maximum range lengths (180 v. 86 m). Home-range areas showed little overlap within the sexes; however, ranges of males overlapped those of females by an average of 37.95%. By comparison with data from a previous mark-recapture study at the same site, radio-tracking produced home-range estimates (MCP) that were greater by a factor of 24.5 for males and 15.5 for females, whereas maximum range lengths were lower for females, but similar for males. The results of this study support the proposition that the rock-dwelling 'P. macdonnellensis' has a more stable home range and undergoes fewer long-range movements that similar-sized arid-zone dasyurids that occupy open environments. These differences likely result from the stability in resources provided by rocky habitats, specifically year-round availability of insects, availability of plentiful shelter sites that are very effective thermal buffers in both summer and winter, and a diversity of accessible microclimates.