Description and analysis of the use of cold harpoons in the Norwegian minke whale hunt in the 1981, 1982 and 1983 hunting seasons.

Until 1984, cold harpoons, i.e. harpoons with no detonating device, were used to hunt minke whales in Norway. To investigate the effectiveness of such harpoons and compare them with alternatives, data on kills using cold harpoons were collected as part of a project dealing with alternative killing techniques for whales. Data on 353 whale kills were collected in 1981-83. The criteria used to determine the time of death were cessation of flipper movement, that the mandible relaxed, or that the whale hung immobile from the harpoon line. These criteria do not take into account any movements caused by spinal reflexes. About 17% of the animals died instantaneously (< or = 10 s). The median survival time was 570 s. Animals died most rapidly if hit in the brain, heart or major blood vessels. If only the lungs were injured, minke whales died less rapidly than terrestrial mammals. For whales that did not die immediately, shooting range, animal size and the angle of the shot all influenced the time to death. The efficiency of cold harpoons could be improved, but their use was no longer considered acceptable, and they were replaced by harpoons with penthrite grenades in 1984.