WIND turbines have caused the deaths of four white-tailed eagles on isolated islands off the Norwegian coast.
Thirty other eagles have failed to return to their nesting sites within the wind farm area on Smola, 9.6km (six miles) northwest of Norway, according to wildlife campaigners.
The dead birds were found between August and December last year. Two had been sliced in half, apparently by a turbine blade. Post-mortem examinations, however, attributed the birds deaths to multiple trauma caused by a heavy blow.
The Royal Society for the Protection of Birds (RSPB) is concerned that wind farms in Britain could exact a similar toll on native and migrating wild birds, especially as the white-tailed eagle, the largest eagle species in Europe, is beginning to thrive at last in the Western Isles of Scotland after a 30-year reintroduction project.
This area has also been earmarked by developers as prime land for the construction of wind farms. Campaigners are already lobbying against a proposed 234-turbine project on peatlands on north Lewis because of the threat it poses to eagles.
The effect of the wind turbines on white-tailed eagles has been revealed after research by the RSPB in collaboration with the Norwegian Institute for Nature Research (NINA) and the Norwegian Sea Eagle Project. Work concentrated on Smola because it is listed by BirdLife International as an important area and because it has one of the highest breeding figures for the bird in the world.
It is possible that other deaths have gone undetected because much of the wind park is rarely visited. Mark Avery, conservation director at the RSPB, said: These findings are shocking, yet may only be the tip of the iceberg. Research on Smola is being stepped up and, if more dead birds are found and even fewer are able to breed, we will be doubly determined to fight wind-farm plans that could cause similar destruction in the UK.
The 68-turbine wind farm on Smola was built by Norway between 2001 and 2005, despite an environmental assessment giving warning that it would pose a threat to the eagles. BirdLife International took the case to the Berne Convention, but the decision was upheld.
Conservationists are to increase checks on the wind farm to determine the extent of the casualties and the numbers of birds being bred this spring.
Researchers have not drawn up final conclusions on the impact on the birds because of a wide variation in their breeding numbers from year to year. There was also intensive construction work at the wind park during the past two years.
Arne Follestad, a research scientist at NINA, said: Breeding results on Smola have been strikingly poor compared with the 30 years before the wind farm was built. We are only halfway through the research, yet, despite their site faithfulness, we are not confident that white-tailed eagles will adapt to the turbines. As older birds die, we do not know if new birds will occupy nest sites within the wind farm.
Stuart Housden, the director of RSPB Scotland, said: The news from Norway is of great concern to us. If white-tailed eagles have died because of wind-turbine collisions, there are major implications for our own eagle populations here in Scotland. We are campaigning hard against the proposed 234- turbine wind farm on north Lewis partly because of the great danger it poses to Scotlands eagles. He said that the peatlands were an environmentally sensitive site protected under European law.
The Department of Trade and Industry said in a statement that it was aware of the Norway study but that there was no evidence that turbines in Britain have been responsible for any major adverse effect on birdlife. A spokesmann added: Wind farms help to reduce carbon emissions and mitigate against climate change, which is an ever greater threat to birdlife.