The early arrival of the first migrating Siberian Bewick's swans could mean that Britain is in for a harsh winter, experts have predicted.

Each winter, around 250 Bewick's swans land at the Wildfowl and Wetlands Trust nature reserve at Slimbridge, Gloucestershire, having flown 2,500 miles from Arctic Russia.

The first six of the flock landed last week, eight days earlier than last year, representing the earliest arrival on record.

It is thought that the earlier the birds arrive, the colder the winter months are likely to be as the swans migrate south to escape the Arctic winds following behind them.

Spokesman for the trust Jules MacKin said: "Clear night skies, cool temperatures and easterly winds over the past couple of days have provided ideal conditions for their westernly migrations through northern Europe.

"This weather is set to continue for the next few days and is likely to encourage more Bewick's to reach British shores."

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