Publication Abstract

Stomach contents analysis of cormorants at some different fishery types in England and Wales

Stomach contents analysis of cormorants at some different fishery types in England and Wales.

I.C. Russell, A. Cook, D.A. Kinsman, M.J. Ives, N. Lower and S.J. Ives

In England and Wales licences to shoot piscivorous birds can be issued where these birds are considered to be causing serious damage to a fishery. However, licences only allow limited numbers of birds to be killed in order to reinforce the effects of other scaring methods also being carried out at the site. A condition of all licences is that any shot birds should be frozen and retained to allow post mortem examination, in particular, to enable information to be collected on the prey species being consumed at particular sites. Detailed stomach analysis is subsequently carried out by the Centre for Environment, Fisheries and Aquaculture Science (CEFAS).

Overall results conform with the view that cormorants are opportunistic predators consuming a wide range of available fish species and sizes. However, marked differences in diet are observed between different fishery sites, believed to be primarily related to prey availability and abundance. The paper reports on the prey composition of cormorants feeding in different river catchments, and within an individual catchment. Comparisons are also made between the diet of birds feeding at stillwater put-and-take trout fisheries with those feeding at stillwater coarse (predominantly Cyprinid) fisheries. The results are discussed in relation to economic considerations and the potential management implications.

Reference:

I.C. Russell, A. Cook, D.A. Kinsman, M.J. Ives, N. Lower and S.J. Ives. 2005. Stomach contents analysis of cormorants at some different fishery types in England and Wales. Cormorants: Ecology and Management at the start of the 21st Century, Proceedings of 5th European Cormorant Conference, Freising, Germany, 255-259

I.C. Russell*, A. Cook*, D.A. Kinsman*, M.J. Ives*, & N. Lower*

Cormorants: Ecology and Management at the start of the 21st Century, Proceedings of 5th European Cormorant Conference, Freising, Germany, 255-259