Fishery discards do not compensate natural prey shortage in Northern gannets from the English Channel

Fisheries modify ecosystem balance by harvesting through marine food webs and producing large amounts of discards subsidizing scavengers. Among them, seabirds are the most conspicuous and have been benefiting from anthropogenic food sources generated by fisheries. However, this modified feeding behaviour also exposes them to threats, such as accidental bycatch on fishing gear and ecological traps set by discards of lower nutritional value...