Common Scoter Ducks' Winter Wandering Surprises Experts

The first efforts to track where Britain's most threatened breeding duck goes in winter have revealed destinations as far apart as the Irish Sea and Morocco.

The population of breeding common scoter ducks has halved in the last 20 years, and it is now a red listed'' species, with only around 40 pairs which nest in a handful of places in the Scottish Highlands.

A tight-knit group from a stronghold around several lochs in the western Highlands is thought likely to be related, and Wildfowl and Wetlands Trust (WWT) experts assumed the ducks would migrate together to a similarly small area to overwinter on the sea.

But when four female ducks were fitted with tracking tags, which were retrieved when the ducks returned after the winter and were re-caught, the data that was downloaded showed they had all gone very separate ways.

One travelled a short distance to the east coast of Scotland's Moray Firth, two went to the Irish Sea, to the North Wales coast and to the east coast of Ireland, and the fourth flew hundreds of miles to the coast of Morocco.

WWT research officer Ed Burrell said: It feels like this mysterious species wants to keep flummoxing any human interest in them.

But in fact their winter wandering gives us some clues to help solve their problems.

The fact they stay apart in winter is a bit like the Royal Family never flying together, it means they can't all be affected by a single issue like a storm or oil spill.

So that means that whatever is causing their decline is more likely to be in the summer when they're all together in the Highlands.''

He said the information would help concentrate investigations into why the ducks - Britain's only wildfowl species on the red list for birds of conservation concern - were in such a perilous situation.

Their breeding sites are managed by Scottish & Southern Energy and Forest Enterprise Scotland, who are working with WWT, RSPB Scotland and Scottish Natural Heritage on monitoring the species.

Nests and feeding areas are being mapped and nest cameras have been installed along with thermometers to monitor the temperature under eggs.

Very little is known about the common scoter in Britain because their nests are well-hidden and spread across remote landscapes, and they spend their winters on the sea.

The global population is thought to be more than a million, breeding in Iceland, Greenland, Scandinavia and northern parts of western and central Russia, and overwintering in the Baltic, the Atlantic, the Mediterranean and as far south as Mauritania.