The eider duck: Fishermen's enemy number one

Now, for the undeniably bad news: the hungry ducks are eating so many shellfish that they threaten the existence of the mussel-farming trade, plied by local people since Roman times.

Yet again, successful conservation and commerce are in conflict. And the mussel farmers and their supporters say the die is loaded in favour of the ducks.

The eider, a protected species, cannot be shot, scared, or even mildly discomforted. This was fine when just 400 arrived each winter from the frozen north. But a warmer Wash, due, say the farmers to global warming, has lured more than 10 times that number this year.

For men such as 64-year-old John Lake, a way of life is ebbing away. "We simply cannot sustain these losses," he said starkly. "For 200 years, my family has done this. But now it's hardly worth it. The birds simply swoop down and eat the mussels."

And there is little he can do. Even wailing at or attempting to frighten the birds can incur a fine of almost £20,000 from English Nature. "We are farmers and it is ludicrous that we're not allowed to scare these birds away in any way, shape or form. It is like having a farmer sow a field of wheat and then not be allowed to do anything to stop the birds eating the seeds." It is time, he said, for the eider to be taken off the protected list.

Losses since the birds returned in autumn are believed to be at least 90 per cent of the total harvest - until three years ago losses rarely exceeded 10 per cent.

But applications to control the birds have been refused by English Nature. Conservationists say that the Wash is home to more than 300,000 birds over the winter months and is the most important UK wetland, recognised as a Site of Special Scientific Interest, with mussels an important food source for various bird species. The eider must be allowed to migrate without interference.

A spokesman for English Nature said: "Eider duck populations will be balanced by what food is available to them. We have to speak up for animals and protect wildlife."

But fishermen protest that they are victims of global warming, whose livelihoods are being devastated by means beyond their control. Their fight has been taken up by the local MP, Henry Bellingham. He said: "The eider duck population is far greater than it previously was, and the mussel lays in the Wash are suffering. It is completely unacceptable."

English Nature recently agreed to test sonic "scarecrow" devices, but the fishermen say they are having little impact.