Increase rates in severely depleted stocks of baleen whales

  • Published source details Best P. (1993) Increase rates in severely depleted stocks of baleen whales. ICES Journal of Marine Science, 50, 169-186.


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 review in 1971–1990 in the North Atlantic, North Pacific and Southern Hemisphere (Best 1993) found that after legislation to prohibit hunting was introduced, significant increase rates were recorded for 10 of 12 baleen whale (Mysticeti) populations of five species or species groups. Estimated increase rates during 7–21 years after hunting was prohibited were significant for four right whale Eubalaena spp. populations (0.07–0.13), three humpback whale Megaptera novaeangliae populations (0.09–0.14), one bowhead whale Balaena mysticetus population (0.03), one gray whale Eschrichtius robustus population (0.03), and one blue whale Balaenoptera musculus population (0.05). Increase rates for the two other monitored populations (one right whale, one humpback whale) were not significant. However, the authors note that more data may have been needed. Four legal agreements were put in place between 1935 and 1968 to protect 44 depleted baleen whale populations from exploitation. Twelve populations were monitored for 7–21 years between 1971 and 1990 using shore, aerial or shipboard counts or mark and recapture methods. The other 32 populations were not monitored.

    (Summarised by: Anna Berthinussen)

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