The influence of environmental factors (mainly the river flow) on the year‐to‐year variability of European eel Anguilla anguilla fluvial recruitment in a small coastal catchment, the Frémur River (north‐west France) was examined. A comprehensive survey of catches from fixed traps at two weirs located at 4·5 km (Pont es Omnes Dam) and 6·0 km (Bois Joli Dam) above the river mouth was carried out between 1997 and 2004. Young pigm...

Mortality of eels Anguilla anguilla in a large shallow lake in France due to predation by the cormorant Phalacrocorax carbo was found to be moderate when compared to fishery catches over a 9 year period. The results show that, contrary to previous extrapolations made at the pan‐European scale, P. carbo predation in shallow lakes is not invariably a major contributor to A. anguilla mortality, even in the presence of large colon...

Thirty migrating silver eels Anguilla anguilla were collected in a river system where algal blooms occurred yearly. Fifty per cent of eel livers were contaminated by microcystin‐LR (mean ± s . d . toxin level: 28·1 ± 22·4 ng g −1 ). Contaminated silver ( v. healthy) eels had lower fish condition. Consequences of this impact for the breeding potential of these migrating eels are discussed.

Changes in the abundance of European eel, Anguilla anguilla L., in the River Frémur, France, were examined over an 8‐year period. Natural connectivity of the river was disturbed by three high dams that inhibited eel upstream migration and reduced recruitment by elvers and yellow eels. After eel passes were installed, fish became more abundant upstream (mean density 0.5 eel m −2 ). Moreover, except in the more upstream areas, n...