Rebuilding seal stocks in the Kattegat-Skagerrak

  • Published source details Heide-Jørgensen M.P. & Harkonen T.J. (1988) Rebuilding seal stocks in the Kattegat-Skagerrak. Marine Mammal Science, 4, 231-246.


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 study in 1979–1986 of a coastal area in the Kattegat and Skagerrak seas, Denmark and Sweden (Heide-Jørgensen & Harkonen 1988) reported that after hunting was prohibited, the abundance of harbour seals Phoca vitulina increased over seven years. Results are not based on assessments of statistical significance. The total abundance of harbour seals in the area was higher nine years after hunting was prohibited (maximum 5,608 seals) than two years after (maximum 2,345 seals). Overall, abundance was estimated to increase by 13% per year during seven years after hunting was prohibited. Hunting of harbour seals was prohibited in 1967 in Swedish waters and in 1977 in Danish waters. Aerial surveys were carried out across the area in each of seven years in 1979–1986. Each year, all haul-out sites in the area (number not reported) were photographed from the air at the end of August using the same methods, equipment, and surveyors. Seal counts were obtained from aerial photographs.

    (Summarised by: Anna Berthinussen)

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