The death is believed to be the first of an eagle due to a collision with a turbine in Ireland or Britain.
Since an eagle reintroduction project started in Killarney National Park in 2007, nine of the birds have died from poisoning.
However, eagle collisions with turbines have been widely reported in Europe and the US. Red kites have been killed by turbine strikes in Scotland.
Dr Allan Mee, head of the Killarney project, stressed that poisoning continued to be the “only real threat” to the project. While collisions with turbines and powerlines were a risk, they were not a serious problem at present.
“Further, most, if not all, breeding pairs in Kerry are likely to be coastal where there are no windfarms, or plans for windfarms, according to Kerry County Council’s County Development Plan,” Dr Mee said.
The latest eagle to die — a three-year-old female released in 2008 — was found below a wind turbine at the Silahertane Wind Farm on the Kerry-Cork border on March 9. The strike severed a wing and fractured a leg.
A postmortem examination at the Regional Veterinary Laboratory, Cork, and toxicological analysis at the State Laboratory, Celbridge, Kildare, revealed very low concentrations of Nitroxinil (Trodax) in the liver.
The amount was not significant and was probably due to consuming traces of the drug in sheep carrion, according to Dr Mee.
“It is sad to lose an eagle in this way, especially as this three-year-old female would have been one of the first birds from the release programme to form the nucleus of a breeding population,” he said.
They had not been aware of any birds roosting in the area of the windfarm at the time. The nearest roost to the farm is 1.5km away and was used regularly by eagles during late 2009 and early 2010 and occasionally since then.
“The risks are probably greatest when birds begin to leave the roost and use the slopes to gain height, during which time they are flying low enough to fly through the wind farm,” Dr Mee said.
“Over the next few years, it will also be important to assess how much white-tailed eagles use the existing windfarms and whether they avoid windfarms to any extent.
“We will also work with wind farm operators to help reduce the risks of further collisions where possible,” he said.
A total of 77 eagles have been released in Killarney to date, 16 of which have died.