Genetic identity and genotype matching of southern right whales (Eubalaena australis) from Mainland New Zealand and the Auckland Islands

It remains uncertain as to whether the NZ subantarctic and Mainland NZ represent two relatively isolated stocks with different histories of exploitation and recovery or a single stock with a poorly understood pattern of migratory habitat use. A third hypothesis, that the Mainland NZ population was extirpated and subsequently recolonised by a range expansion from the NZ subantarctic, is also possible. Here we construct DNA profiles for southern right whales sampled around the NZ Mainland (n=31) and NZ subantarctic (n=934) by genotyping of microsatellite loci (up to 14 loci, average 12.7 loci), sequencing of the mtDNA control region (minimum of 500bp) and sex identification. Four matches between the NZ subantarctic and Mainland NZ were identified, the first time any such match between the two areas has been documented. These results, and other available data, are most consistent with either the one stock or recolonsiation hypotheses.