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While most people would be content to throw bread to the ducks, Jean Keene doles out salmon and sardines by the bucketload to 200 bald eagles.

Ms Keene, 84, has estimated that since 1978 — when she threw her first fish to one of the birds, America’s national symbol — she has provided them with almost 500 tonnes of food.

Every year from December to the end of March she spends an estimated £15,000 on fish for the birds. During the winter season, before they fly away to mate and raise their young, the eagles get through about 50,000lb (22 tonnes) of fish provided by Ms Keene, who lives in Homer, Alaska.

But so many birds ended up arriving at the town in search of a free lunch that residents complained that they were just as much of a pest as the pigeons in Trafalgar Square, London.

Many said that the eagles — which have a 6ft wingspan — were scaring away other wildlife, including sea otters and sea birds such as kittiwakes, and claimed that they were attacking pet cats and dogs.

The eagles increasingly came to be regarded in the town as the bird “of bad moral character” so loathed by Benjamin Franklin. “I wish that the bald eagle had not been chosen as the representative of our country,” he wrote. “He does not get his living honestly.”

In 2006 laws were introduced to ban the feeding of birds in Homer, but an exception was made for Ms Keene, although she will also have to stop in 2010. As long as her health permits, she intends to carry on right up to the deadline, she said.

Half the eagles she feeds have already flown away this year and the remaining ones will have to fend for themselves again from tomorrow — winter feeding has to stop on April 1.

Despite criticism by some of Homer’s residents that the birds are quite capable of finding their own food and that the fish handouts are upsetting the natural balance, Ms Keene remains defiant. “The reason I feed the eagles for three months in the winter time is because they are hungry and it is hard for them to find food,” she said.

When she first started feeding the birds she was working at a fish canning factory and tossed them occasional scraps. Now she calculates that she can get through 1,000lb in less than three days.

“I have been doing it for 30 years and have a safe place for them to feed. I also pick up injured birds,” she says, pointing out that “a lot of money is spent to heal them up at the raptor centre instead of letting nature take its course”.

Ms Keene, daughter of a Scot and an Englishman, said: “Ninety per cent of the people want the eagles here and they only make a mess sometimes in the feeding area here — not around town or homes. They will take chickens or really small pets if they are hungry and have the opportunity, but so do hawks and owls.”

In the 17th century there were an estimated half a million bald eagles in North America, but the number crashed when Europeans reached the continent. In Alaska a bounty was offered to people who killed the eagles and from 1917 to 1953 more than 128,000 were slaughtered.

Two decades later, however, numbers had bounced back and there are now an estimated 50,000 living in America’s northernmost and largest state. In the rest of the US numbers remain low, perhaps 6,000 breeding pairs, but they are recovering. In Canada a further 50,000 are thought to thrive.

Ms Keene added: “Never in my wildest dreams did I think I would still be feeding them at 84 years of age. I only had two or three birds in 1978.”

Bald eagles . . .

— Are not bald, though they can appear so from a distance. They have white feathers on their heads

— Were officially named the US national bird in 1782

— Live in North America from Alaska to Florida

— Have been blown as far as Europe by storms

— Are not America’s biggest bird, which is the Californian condor

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