Bewick swans are the world's rarest breed

They fly about 2,500 miles from Siberia every autumn and winter, stopping across Europe before arriving in the UK.

More than 300 of the swans have already arrived at the Slimbridge centre, close to the River Severn, compared with 141 this time last year.

At least 100 more are expected as temperatures fall.

About 20% of this year's arrivals are cygnets, compared with only 3% in previous years.

Most hatched only 12 weeks ago, before making the long migration from Siberia.

Oldest flier

More than 9,000 of the swans have been recorded at the centre in the past 38 years.

Each is recognisable by its individual bill pattern and is named by staff as part of continuing research into the birds' behaviour.

The oldest of the returning birds is Windfall, a male spending its 21st winter at Slimbridge.

A pair called Laugh and Chirpy have arrived with new cygnets, as well as those born last year.