Fish removal in gravel lakes significantly improves feeding success and density of tufted ducks Aythya fuligula and increases general abundance of waterfowl

  • Published source details Giles N. (1994) Tufted duck (Aythya fuligula) habitat use and brood survival increases after fish removal from gravel pit lakes. Hydrobiologia, 279, 387-392


This study is summarised as evidence for the following.

Action Category

Reduce inter-specific competition for food by removing or controlling competitor species

Action Link
Bird Conservation
  1. Reduce inter-specific competition for food by removing or controlling competitor species

    A controlled, before-and-after study from 1986-1990 on one gravel pit lake in Great Linford, UK (Giles 1994) found that tufted duck Aythya fuligula feeding success and abundance increased significantly following fish removal from a selected area of the lake in 1987-8 (from 0 to 149 brood observations), while numbers declined in areas where fish were not removed or were reintroduced (from 92 to 4 brood observations). Average brood size increased from 3 to 4 post fish-removal. Additionally, both invertebrate and plant-eating wintering waterfowl increased their use of the lake and species new to the lake began to nest and produce young. In total, 396 kg / ha of fish biomass was removed from the lake during 1987-1988 through seine netting and electro-fishing.

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