Western Daily Press (Saturday)
Swans’ latest migration in years is due to climate
APAIR of Bewick’s swans have arrived at a West Country nature reserve, heralding the official start of winter but the latest since 1965 – highlighting global warming.
The birds landed at WWT Slimbridge Wetland Centre, in Gloucestershire, early on Thursday – which also marked the Wildfowl & Wetlands Trust’s 76th anniversary.
The swans make the 2,000-mile migration annually from the coldest parts of Russia to seek out comparatively warmer weather.
The first Bewick’s to return this year were ‘Fortune Two’ and ‘Combo’. Fortune Two is 19 years old and first arrived as a cygnet at Slimbridge with his parents Sauber and Manero in the winter of 2003-4.
He paired with Combo in the winter of 2005-6 and they have returned every year since, but have only managed to bring back cygnets once in 2013, which highlights the breeding challenges these swans have faced in recent years.
The arrival of Bewick’s swans hails the start of winter but this year is the latest arrival for the species at the Gloucestershire site since 1965.
Dr Julia Newth, ecosystem health and social dimensions manager at
WWT, says it is likely due to mild climate conditions.
She said: “The arrival of the Bewick’s swans this year is later than usual. It has been a mild autumn in the Arctic so the Bewick’s have left their breeding grounds later.
“The Arctic is warming twice as fast as the rest of the planet and there are significant changes happening on the breeding grounds.
“Although we don’t fully know the impacts yet, changes in the weather do influence migratory patterns.
“Migration patterns are changing in other ways, too. The Bewick’s swans are not wintering as far west as they used to and this is linked to the milder winters in Europe.”
“The UK stronghold for these birds is in and around our wetland sites at Slimbridge and Welney (Norfolk), with some around Martin Mere (Lancashire). These wetland habitats are vitally important wintering grounds for these amazing birds.”
Bewick’s are small white swans with a black and yellow bill. WWT was founded by Sir Peter Scott, who dedicated much of his time watching and studying the species.
He was one of the first people to notice that each bird has a unique bill pattern, making it possible to identify individuals.
The WWT conservation team based at Slimbridge have been using this technique to identify and record individual swans for more than 50 years. Over that time, the comings and goings of individuals and family dynasties has led to over 10,000 swans being recorded.
Bewick’s tend to be long-lived, but usually only two or three cygnets per family make it to their wintering sites in north-west Europe, and less than half of the population makes a breeding attempt each year.
Numbers decreased from around 29,000 in 1995 to approximately 20,000 recorded in 2015, and conservationists are still trying to confirm the reasons for the decline.
Research suggests the swans have suffered a series of poor breeding years and this is likely to be contributing at least in part to their decline.
They also still face other threats along their migratory route, like illegal hunting and lead poisoning.
WWT works to support field conservation work for the protection of Bewick’s swans and for the vital wetlands they need to survive.
It supports the Swan Champions initiative out in their Arctic breeding grounds. Concerns for the fate of Bewick’s swans among local residents has promoted them to start an initiative to unite scientists, hunters and the public in championing swans and their wetland home while reducing the hunting of swans.
This network of people includes prominent figures representing indigenous groups, conservation organisations, academic and educational institutions, tourism, and agencies and members of the regional government.
Activities focus on improving the ability of hunters to recognise protected water birds and encouraging them to follow the laws that protect them.