Biology and Ecology
Feeding
Common minke whales have varied diets, with many populations feeding on a vairety of small schooling fish ranging from anchovies to mackerel, herring, capeline and cod. Some populations are also known to eat plankton, and krill is an important prey species for common minke whales off of Greenland. Antarctic minke whales rely almost exclusively on krill – as do so many other species of blaeen whale that feed in Antarcitc waters2.
Social structure reproduction and growth
Minke whale seasonal movements are less predictable and less well defined than many other species of baleen whales that have a very clear seasonal migratin pattern between summer feeding grounds and winter breeding grounds. Although there may be some seasonal movement in some pouplations, breeding can occur year-round, and calves are born roughly 10 months after conception. Calves remain with their mothers for 5-6 months, and females reach the age of reproduction at 7-8 years. Female minke whales appear to be able to give birth to one calf every year, unlike many other baleen whales that produce only one calf every 2-3 years2,5.
Threats and conservation status
Natural predators
Killer whales are the only known natural predator of minke whales. In fact, minke whales may form a major component of the diet of some forms of killer whales in the Antarctic2.
Human induced threats
Like most species of whales and dolphins, minke whales can become entangled in fishing gear6,7. Minke whale bycatch appears to be particularly high off the coasts of Japan and Korea3. Another potential threat is the bioaccumulation of contaminants like organochlorines and DDT in minke whale blubber.8-10
Conservation status
Considered too small and too fast to be worth hunting, minke whales were overlooked by most whalers throughout the 19th and 20th centuries, and only became the focus of intensive whaling efforts when most other species were severely depleted and difficult to locate. As such, most minke whale populations were less severely affected by whaling than other species2. Today however, they are one of the few species of whale to still be hunted in significant numbers in countries that have lodged objections to the current IWC moratorium on whaling, such as Iceland and Norway, and also by Japan who left the IWC in 2019 and conduct commercial whaling in the North Pacific.
Common minke whales are difficult to assess globally due their diffuse distribution. However, they are designated as Least Concern under the IUCN Red List for threatened species, due primarily to the fact that they were less depleted by commercial whaling than other baleen whale species. Some populations are subject to annual hunts which are deemed to be sustainable by the countries that implement the hunts (Iceland, Norway, and Japan).
Antarctic minke whales are considered Data Deficient under the IUCN Redlist. Currently they appear to number over 500,0003,15. Analyses revealed that their numbers increased from 1930 until the mid-1970s, declined over the period from the mid-1970s until about 1988, and then remained more or less stable over the past 20 years11 6. In other words, the abundance estimated during the 1991/92 – 2003/04 southern hemisphere summer seasons was about 30% lower than that estimated during the 1985/86-1990/91 southern summer seasons15. .3 The reasons for this have not fully been explained. Antarctic minke whales are listed under Appendix II on the convention on Migratory Species (CMS). The eastern North Atlantic as well as the eastern north Pacific subspecies are included in Appendix II of CMS.
Read a detailed assessment of the status of North Atlantic minke whales conducted by the IWC Scientific Committee.
Minke whales and whale watching
Please see the IWC Whalewatching Handbook