Seabirds chase boats for meals

Fishing boats are acting as the marine equivalent of fast food outlets for some seabirds!

Satellite tags attached to gannets show that the birds can spot a trawler from eleven kilometres away. The seabirds then abruptly change course in the hope of grabbing a free meal in the form of the discarded by-catch that the fisherman dump overboard when they empty their nets.

Writing in Current Biology, Exeter scientist Thomas Bodey and his colleagues have found that the birds can distinguish between boats that really are fishing and those just drifting or are not trawlers.

Analysing the birds' feathers or blood can then reveal what proportion of the animals' diets is being supplied by fishing vessels.

Although population studies show that, relative to many other seabirds whose numbers are in decline, gannets appear to be in good shape, scientists are concerned that, as food picked up this way isn't part of their normal diet, there could be long-term health consequences for the birds.