The geese travel from the Arctic (Pic courtesy of Mike Lane)
The big freeze in Europe has helped attract record numbers of rare geese to an island off Northumberland.
About 4,000 light-bellied brent geese have landed at the Lindisfarne National Nature Reserve on Holy Island.
Normally only half of the species' world population of 6,000 come to the island from the Arctic, with the remainder wintering in Denmark.
But experts say frozen wetlands in the Scandinavian nation has led to more seeking refuge in England.
The coastal climate of the Lindisfarne reserve still provides an attractive feeding site for the birds, despite the UK suffering from prolonged cold weather earlier this winter.
Reserve manager Andrew Craggs said: "It is a sign of just how widespread the big freeze has been that these geese are present at Lindisfarne in such large numbers.
'Never touched down'
"The arrival of the geese is a treat for wildlife watchers, but it is a sobering thought that virtually the entire world population of these birds rely on only a couple of locations in Europe for their survival in winter."
Carl Watts, the reserve's community outreach officer, said mystery surrounded the location of the remaining light-bellied brents, with no sightings reported in Denmark or the rest of Europe.
He said: "It was expected that they would arrive at Lindisfarne but they never touched down.
"The geese are not radio tracked and Birdlife International, which works globally to conserve birds, has not reported any sightings in Europe to us.
"One possibility is that some could have died, but we hope that they have been able to find new grounds on which to winter."
The birds traditionally arrive in November after travelling from the Arctic island of Svalbard and they normally head back in March.