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Providing evidence to improve practice

Individual study: Provision of artificial fish refuges reduces fish predation by great cormorants Phalacrocorax carbo in ponds near Reading, Berkshire, England

Published source details

Russell I., Parrott D., Ives M., Goldsmith D., Fox S., Clifton-Dey D., Prickett A. & Drew T. (2008) Reducing fish losses to cormorants using artificial fish refuges: an experimental study. Fisheries Management and Ecology, 15, 189-198

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Provide refuges for fish within ponds Bird Conservation

In Berkshire, England, a controlled cross-over trial (in the winters of 2003 and 2004) found that great cormorant Phalacrocorax carbo foraging success was lower in a pond with artificial refuges (Russell et al. 2008), compared to a control pond (on average, 67% less fish weight consumed/cormorant visit); fish loss was significantly lower (79% less fish weight lost); and there were 77% fewer cormorant visits. Two adjacent ponds (45.0 x 27.2 m; 1.35 m depth) were used, with provided in one pond each year. Refuges were 12 mesh covered cages (2 x 2 x 1.2 m high) in two blocks of six, with shade cloth and containing 4-6 tree saplings to provide cover. At commencement of each trial, ponds were similarly stocked with freshwater fish. Fish weight was recorded at the beginning and end of each trial.