Rate of increase and current abundance of humpback whales in west Greenland

  • Published source details Heide-Jørgensen M.P., Laidre K.L., Hansen R.G., Burt M.L., Simon M., Borchers D.L., Hansen J., Rasmussen M. & Dietz R. (2012) Rate of increase and current abundance of humpback whales in west Greenland. Journal of Cetacean Research and Management, 12, 1-14.


This study is summarised as evidence for the following.

Action Category

Prohibit or restrict hunting of marine and freshwater mammal species

Action Link
Marine and Freshwater Mammal Conservation
  1. Prohibit or restrict hunting of marine and freshwater mammal species

    A before-and-after study in 1984–2007 in a pelagic area in the North Atlantic Ocean, Greenland (Heide-Jørgensen et al. 2012) found that after legislation to prohibit hunting was introduced, the abundance of humpback whales Megaptera novaeangliae increased over 22 years. The estimated abundance of humpback whales in summer feeding grounds was higher 22 years after hunting was fully prohibited (1,020 whales) than before (99–271 whales). Overall, abundance was estimated to increase by 9.4% per year from 1984 to 2007. Commercial whaling of humpback whales was prohibited in 1955, although low level harvesting continued until full protection was put in place in 1985. Aerial transect surveys were conducted in July–September during one year before full legal protection (1984) and during seven years after (1985–1989, 1993, 2005 and 2007). Aircraft flew over the area at 600–750 feet and 3–4 observers recorded sightings of humpback whales along 41–103 transects/year.

    (Summarised by: Anna Berthinussen)

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