Aer Rianta is preparing to clip the wings of swans who are posing a hazard to aircraft at Shannon.
The airport management company has received a licence from the Department of the Environment to clip their wings, as a short-term measure to stop them crossing the airfield from a lagoon along the lower Shannon estuary to Lough Gash at Newmarket-on-Fergus.
Managers decided against seeking a licence to shoot the swans.
Last year air traffic control recorded 14 incidents of the mute swan, the breed using the lagoon, crossing the airfield at low level. There were no "contact strikes" but the most serious incident in December resulted in an Airbus 330 being forced to overshoot the runway and come back again to land. Over 230 swans have been counted in recent years during the summer, reducing to 20 in winter.
Ropes and buoys placed on the lagoon to deter the swans have proved ineffective and Aer Rianta is planning to clip their wings "as soon as possible". The swans will be lured into a cage trap to clip their wings, which stops the birds flying for a short time.
When the water levels are low the swan population is reduced and Aer Rianta has sought to drain the lagoon to a "swamp", to discourage the swans. However, Dúchas, the heritage service, has designated the lagoon as a "candidate special conservation area" because of its habitat and a licence is required to drain the lagoon. Dúchas is emphatic that under the EU Habitat Directive the lagoon can only be drained if Aer Rianta "provides an alternative but similar wetland habitat", according to sources.
The Department of the Environment confirmed it has issued a licence, conditional on the provision of another habitat.
However, Mr John Murphy, a Co Clare member of Birdwatch Ireland and co-author of a forthcoming book on the lagoon, believed it would be impossible to create a similar habitat.
He said the best option would be to "drop the levels lower than what they normally are and let them up again for the winter".
An Aer Rianta spokesman said the company was "concerned that the presence of a large number of swans close to the runway could constitute a threat to public safety".
