Swan 'divorce'

The Bewick's swans have returned to winter at the Wildfowl and Wetlands Trust centre at Slimbridge - but both have brought new partners.

It is not unheard of for the birds, which usually mate for life, to find a new mate but it tends to be because one of the pair has died, they said.

First suspicions of the rare event were raised when male swan Sarindi turned up in the annual migration from Arctic Russia without his partner of two years Saruni and with a new female - newly-named Sarind - in tow. The pair's arrival led conservationists to fear the worst for Saruni. But shortly afterwards Saruni arrived at the wetlands site - also with a new mate, Surune.

Julia Newth, wildlife health research officer at Slimbridge, said the situation had taken staff by surprise.

She said swans tended to have "real loyalties to one another" and long partnerships.

"As long as they are both still alive, they will try to stay together. If they have a change of mate it is perhaps because of mortality, not necessarily through choice," she said.

Ms Newth said the old pair had not acknowledged each other with any signs of recognition or greeting - even though they are occupying the same part of the small lake.

As for why they may have split, she said: "Failure to breed could be a possible reason, as they had been together for a couple of years but had never brought back a cygnet, but it is difficult to say for sure."