The effects of killing and removal on the abundance of grey herons at fish farms

  • Published source details van Vessem J., Draulans D. & De Bont A. F. (1985) The effects of killing and removal on the abundance of grey herons at fish farms. Proceedings of the International Union of Game Biologists 17th Congress, 337-343.


This study is summarised as evidence for the following.

Action Category

Translocate birds away from fish farms

Action Link
Bird Conservation
  1. Translocate birds away from fish farms

    A study in Belgium found that capturing grey herons Ardea cinerea (using clap nets) at a fish farm and releasing them at various distances away (Van Vessem et al. 1985) did not appear to reduce heron abundance. Catching herons was very time-consuming (a maximum of four, but usually 1-2 caught each day). Some birds released 30 to 80 km returned within a month; one released 150 km away reappeared the following winter. Numbers relocated were too low to reduce heron abundance and relocation was considered ineffective.


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