Evaluating the evidence for population structure within Antarctic blue whales
A.R. Lang, F.I. Archer, C. Attard, C.S. Baker, T. Branch, R.L. Brownell Jr., D. Buss, J. Jackson, N. Kelly, L. Moller, P. Olson, A. Sirovic and A. Sremba
International Whaling Commission
Previous assessments have assumed that Antarctic blue whales comprise a single circumpolar population. For the upcoming assessment, it has been proposed that the base case continue to focus on one circumpolar assessment. However, given that effort has been higher in some areas (in particular, Management Area III, where c.200 whales have been photo-identified) than it has been in others, the potential for doing regional assessments (i.e., within one or a few areas) was discussed at SC68a. Conducting regional assessments would require an understanding of the degree of connectivity between areas, and the SH sub-committee agreed to review the available evidence for population structure to evaluate the potential for including regional assessments as sensitivity analyses. Here we summarize the available evidence from different research fields.