Do Antarctic Minke whales migrate to Northern Hemisphere?

January 2011. The Antarctic Minke whale (Balaenoptera bonaerensis), and the common Minke whale found in the North Atlantic (Balaenoptera acutorostrata acutorostrata), undertake synchronized seasonal migrations to feeding areas at their respective poles during spring, and to the tropics in the autumn where they overwinter. They have always been considered as separate species that did not mingle or interbreed.

It has always been thought that the differences in the timing of seasons between hemispheres prevent these species from mixing. However, based upon analysis of mitochondrial and microsatellite DNA profiles, it has been found that there must be some mixing between the two. This has been shown by the observation of a single B. bonaerensis in 1996, and a hybrid with maternal contribution from B. bonaerensis in 2007, in the Arctic Northeast Atlantic. Paternal contribution was not conclusively resolved. This is the first documentation of B. bonaerensis north of the tropics, and, the first documentation of hybridization between Minke whale species.

See the full scientific paper here.