Of the 100 birds released in Killarney National Park over a five-year period, 30 have died, including 12 from confirmed poisonings, but pairs continue to form and several could hatch chicks in 2015, according to the Departments of Arts, Heritage and the Gaeltacht.
Four new territories have been set up this year, but any further deaths could “slow or even halt’’ the creation of a viable population, says project manager Allan Mee, in a report for 2014.
Fourteen pairs held territory in 2014. At least five pairs built nests and seven pairs laid eggs. As in 2013, one pair nested successfully again, with a single chick fledging from a nest near Mountshannon, Co Clare.
Others failed to hatch for various reasons, such as poor weather. One new pair, in Co Galway, continued incubating at least two weeks after the hatch date.
However, the Galway pair was disturbed repeatedly by sightseers and fishermen in small boats during incubation, resulting in birds leaving eggs exposed for at least 20 minutes at a time and causing the eggs to become chilled, says the report.
Another pair also hatched at least one chick, but this breeding effort failed in its second week after hatch probably due to poor weather and inexperience. A third pair incubated up to hatching.
Bad weather in spring also appeared to take its toll.
Future breeding sites, in Fermanagh, Longford and Cavan, have also emerged. One Irish 2007-released female bred and hatched three chicks at a nest in Argyll with a Scottish male.
The expansion of the breeding population to counties Cork and Galway, as well as Kerry and Clare, is very encouraging, says the report. Pairs have settled mainly in a northerly direction, up to 150km, as opposed to the south coast.
Three eagles, all males, have been found dead this year, including one of the first two Irish-bred chicks to fledge from a nest in Lough Derg, in 2013. This bird was discovered near Ballinderry, Co Tipperary, with 49 shotgun pellets in its carcass.
Investigations were carried out by National Parks and Wildlife Service and gardaí, but nobody has been prosecuted.
“The loss of this bird, the first to fledge from a nest in Ireland, was a blow to the project and caused national outrage in the media,” said Dr Mee.