Comments: For many years, it was thought that there was one species of minke whale. Recent studies indicate the existence of multiple species (Wada and Numachi 1991). DNA data indicate that the Northern and Southern hemisphere populations are clearly distinct; the North Pacific and North Atlantic populations appear distinct from each other; a Southern Hemisphere dwarf form also is genetically distinct; whether these differences are indicative of species, subspecies, or "stock" rank is unclear (see Dizon et al., 1992, Conservation Biology 6:24-36; IUCN 1991). The Antarctic minke whale (B. bonaerensis) appears to be genetically closer to sei and Bryde's whales than it is to Northern Hemisphere minke whales (B. acutorostrata). Without explanation, the North American mammal checklist by Baker et al. (2003) referred to Balaenoptera acutorostrata as the "northern minke whale," implying that they recognized one or more additional species in the Southern Hemisphere. Mead and Brownell (in Wilson and Reeder 2005) recognized two species of minke whales, Balaenoptera acutorostrata (common minke whale, with a worldwide distribution) and B. bonaerensis (Antarctic minke whale, in the Southern Hemisphere). Balaenoptera acutorostrata includes the unnamed dwarf minke whale of the Southern Hemisphere.