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Providing evidence to improve practice

Individual study: 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 intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

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

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.