Overview of The Status of Rock-wallabies in South Australia.

Abstract

The status of Yellow-footed Rock-wallabies (Petrogale xanthopus) and Black-footed Rock-wallabies (P. lateralis) in South Australia was assessed by comparing recent survey and census data with previously collated information about the distribution and relative abundance of each taxon. Petrogale xanthopus has maintained most of its known geographic range within the state; however, its relative abundance has declined significantly and 35 (or 15%) of a total of 229 recorded colonies have become extinct since European settlement. Eight of these colony extinctions have occurred over the past 25 years; three of them since 1981. As this species is continuing to decline it should be regarded as threatened within the state. Petrogale lateralis has at least two sub-species which occur in South Australia. Petrogale lateralis pearsoni is endemic to the state and occurs on offshore islands. Since 1960 its natural occurrence of about 3-500 individuals on North Pearson Island has been expanded to four other islands through translocations and the total population is now about 700-1100 animals. This subspecies, while not occurring in large numbers, is nonetheless relatively secure due to the additional populations established and the fact that these are on islands isolated from most mainland threats. The mainland subspecies, Petrogale lateralis MacDonnell Ranges race, by comparison has suffered a drastic reduction in both geographic range and abundance to the point where it is South Australia’s most critically endangered vertebrate taxon. It has declined from being a very common species in the state’s far north- west to only two known, widely separated, colonies which total less than 100 animals between them. Management and research recommendations are provided.