By BBC Northern correspondent Richard Wells

For Whooper Swans, a 20-acre lake near Southport in northwest England is a winter resort that's never been more popular.

They have recently migrated a thousand miles across the north Atlantic from their native Iceland to escape wind and sub-zero temperature and a record number of them have landed at Martin Mere, a reserve run by the Wildfowl Trust.

In the l980s just a handful of Whooper Swans spent the winter months at Martin Mere. Today the figure stands at more than l,300.

The reserve manager Chris Tomlinson says there are two reasons for the growing popularity of Martin Mere. It provides safety from predators like foxes and three times during daylight hours staff of the Wildfowl Trust put out food for the birds.

Half a tonne of grain and 10 tonnes of waste potatoes are consumed by the birds each day.

The potatoes are donated by local farmers. It is in their own interests to do so. Food left out by the sides of the lake stops the swans flying onto nearby fields and eating more expensive crops such as carrots destined, eventually, for supermarket shelves.

One in six of all the Whooper Swans which visit England at this time of year now winter at Martin Mere. It allows ornithologists to study the birds closely.

Later this month it is expected that some birds will be caught and ringed to help monitor their movements and breeding success once they have returned to their native Iceland.

The research will build on work already done. One bird ringed at Martin Mere in l993 is still coming back.

The l,335 Whooper Swans are expected to remain at Martin Mere for several more months before they return to Iceland where they will breed.

Then come the autumn, hopefully, it will be back to Martin Mere bringing their young for their first taste of the ready meals on offer.