Provenance of a New Zealand brush-tailed rock-wallaby (Petrogale penicillata) population determined by mitochondrial DNA sequence analysis

Modern molecular genetic techniques provide a valuable means to address que stions concerning the origins of naturalized populations. Brush-tailed rock -wallabies (Petrogale penicillata), of unknown provenance, were introduced to New Zealand from Australia in the early 1870s. While the introduced wall abies prospered in New Zealand, their antecedents in Australia experienced widespread local population extinctions as part of a drastic, widespread an d ongoing decline. In this study, a polymerase chain reaction-single-strand conformation polymorphism analysis was undertaken of mitochondrial DNA (mt DNA) control region sequences from P. penicillata in New Zealand (n = 18) a nd throughout the species' native range in southeastern Australia (n = 54). A single mtDNA haplotype was identified in New Zealand, while 17 haplotype s were found in sampled Australian populations. Phylogenetic analysis (583 by sequence) revealed the presence of three divergent mtDNA groups within A ustralian P. penicillata, with each group showing distinct geographical cir cumscription. The New Zealand haplotype consistently clustered within the c entral New South Wales group and was most similar (0.55% sequence divergenc e) to a haplotype from Winmalee, just west of Sydney. It seems likely then, that the New Zealand population of P. penicillata was founded by animals c aptured near Sydney in the late 19th century. Since P. penicillata in this region have experienced widespread population declines and extinctions, the naturalized New Zealand population represents a potentially valuable conse rvation resource for Australia. However, the unusual history of New Zealand 's P. penicillata presents unique challenges to Australian wildlife manager s.