Antarctic Minke Whale, Balaenoptera bonaerensis

The Antarctic minke whale (Balaenoptera bonaerensis), also known as the southern minke whale, is one of two minke whales within the Mysticeti suborder, which contains baleen and rorqual whales. It can be found in every ocean in the southern hemisphere, residing in Antarctic waters in the summer months and northern waters in the winter months, where its range overlaps that the smaller common minke whale. The Antarctic minke whale was once classified with the common minke whale as a single species. Genetic testing showed that the two species varied enough to be classified as distinct species, although they are closely related. It is one of nine species of rorqual whales.

The Antarctic minke whale is relatively small, reaching an average length between 24 and 35 feet with a weight of up to 9.1 tons. Females are typically longer than males reaching an average length between 27 and 38 feet. It is dark grey in color on its dorsal side and whitish in color on the underbelly. A light grey stripe appears on each side between the dark color of its topside and the light color of its underbelly. The flippers are typically dark in color with light sides.

Minke whales have been subject to hunting since the whaling season of 1950 to 1951, although the records studied did not state whether the first minke whale hunted was an Antarctic minke whale or a common minke whale. By 1958, 493 whale catches had been recorded. This number had risen to large numbers killed each year, until 1968 when 605 whales were killed. About 3,021 whales were killed in 1972. In order to conserve the minke whale populations, the IWC set a quota of 5,000 whales in one season, but whalers went over that quota by about 745. This quota was initiated in the whaling season of 1973 to 1974 in the Soviet Union and Japan, where the quota was to be filled, but whalers demanded a larger quota of 7,713 whales. Between 1975 and 1987, the number of whales killed varied between 5,000 and 7,000, with a peak of 7,900 whales in 1977. By the end of 1987, commercial whaling of the Antarctic minke whale in the entire southern hemisphere ceased.

Although commercial whaling of the Antarctic minke whale is no longer legal, it is still legal to capture a whale for scientific purposes. Under Article VIII of the IWC, Japanese scientists take one factory ship and a few smaller ships to spot the whales through the Southern Ocean. The first of these scientific projects began in 1987 to 1988, when the Japanese Research Program in the Antarctic (JARPA) culled 273 Antarctic minke whales. This number rose to 330 and 440 whales in following years. The second project conducted by JARPA began in 2005 to 2006. This was known as a “feasibility study” and consisted of the culling of 850 minke whales from the Antarctic and 10 fin whales. This quota was not filled between 2006 and 2007, during the second whaling season, due to a fire, with only 508 whales being caught. In 2007 to 2008, environmental groups stopped the culling of the whales and caused JARPA to catch 551 whales, instead of the quota of 850.

The Antarctic minke whale is listed in the Convention on the Conservation of Migratory Species of Wild Animals (CMS) in Appendix II as a species with an undesirable conservation status. This means that it would greatly benefit from further study and international cooperation to maintain its population numbers. This species can also be found in the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region. Because there is not much information about the Antarctic minke whale regarding its habits, population numbers, threats, and resilience, it appears on the IUCN Red List with a conservation status of “Data Deficient.”

Image Caption:  Minke whale in Ross Sea, Antarctica. Credit: Brocken Inaglory/Wikipedia (CC BY-SA 3.0)