SOCIAL-STRUCTURE AND PATTERNS OF MOVEMENT OF THE WESTERN PEBBLE-MOUNDMOUSE, PSEUDOMYS CHAPMANI, AT MARANDOO, WESTERN-AUSTRALIA

Mounds of the western pebble-mound mouse, Pseudomys chapmani, are foun d throughout the species' Pilbara range in areas with iron-ore deposit s of economic significance. Translocation techniques are being examine d as a means of minimising the impact of mining on this species. In th e absence of detailed information on the biology of P. chapmani, trans location is inadvisable. To provide such basic information, animal den sities, mound demographics and population sizes, and home-range end co re-area sizes were obtained by a combination of trapping and radio-tra cking. Mounds of P. chapmani were found to be inhabited by social grou ps of up to 12 animals. Estimates of home-range size gave mean (+/- s. e.) values of 14.4 +/- 6.7 ha and 4.6 +/- 2.7 ha for males and females , respectively; core areas were recorded at 0.93 +/- 0.29 ha sor males and 0.29 +/- 0.16 ha for females. Considerable overlap of home ranges was recorded between individuals from the same and different mounds. Overlap at the core-area level occurred only between individuals from the same mound. The high level of social complexity and mound fidelity indicates that translocations should be directed at the level of the social group rather than at the level of the individual.