At least 15 Whooper Swans were electrocuted at a single site in north-east Co Donegal earlier this autumn, according to BirdWatch Ireland.
The swan carcasses were discovered lying under electricity lines near the village of Carrigans, close to the border with Northern Ireland. BirdWatch Ireland staff member Daniel Moloney travelled to the scene and confirmed that the swans had collided with the wires in flight and that they had each been electrocuted. A high proportion of the dead swans were juveniles.
It appears that the deaths were the result of multiple, separate collisions with the electricity wires over a period of several weeks. Some of the birds were freshly dead, while others showed varying levels of decomposition, indicating that they had died on different occasions.
The culpable wires were fitted with "deflectors", which are supposed to make them more visible to flying birds, but these appear not to have worked satisfactorily in this case. Indeed, several of the deflector devices had been knocked off the wires due to the swan collisions, further reducing the wires' visibility.