New mink threat to Irish seabird islands

American invaders have now reached Puffin Island

September 2011: American mink are beginning to colonise some of Ireland's most remote offshore islands – prompting calls for immediate action.

DANGER: American mink. Picture: Peter Trimming

The islands, thanks to their inaccessibility and lack of mammalian predators, are home to some of the most important seabird colonies in Europe. But now the mink, voracious predators of nesting birds, eggs and chicks, are threatening these safe havens.

Bird Watch Ireland's senior seabird conservation officer, Dr Stephen Newton, explains the Heritage Council-funded efforts to solve the problem.

‘Ireland has a special international responsibility for seabirds: indeed several of our west coast islands in Kerry are truly globally special places for species such as the Manx shearwater and the European storm petrel.'  

Stock for fur farms
‘These birds are nocturnal and nest underground in burrows or rock crevices, and so are less well known than the charismatic puffin,' said Dr Newton, ‘which is easily seen from May through to July at spectacular sites such as Great Saltee in County Wexford, Skellig Michael, County Kerry and the Cliffs of Moher in County Clare.'

American mink are non-native, aquatic carnivores and capable of swimming out to islands located a moderate distance from the mainland. First brought to Ireland in the middle of the 20th Century as stock for fur farms, many escaped or were deliberately released and have now spread throughout much of the country.

‘Quite how far mink can swim is not really known, but they have certainly reached Puffin Island, which lies only 300-400 metres off a very inaccessible section of the Kerry coast,' said Dr Newton. ‘The island is a BirdWatch Ireland reserve, protected for its large breeding colonies of Manx shearwater, storm petrel and, not surprisingly, puffins.'

INVADED: Puffin Island. Picture: Lars Soerink

These carnivores can do irreparable damage
‘The first mink was recorded on the island in 2007 and mink were certainly still present in April 2011, when several dead shearwaters and a recently killed petrel were found.'

It is now hoped the work of BirdWatch Ireland and the Heritage Council can now rescue the islands from the threat.
‘Grant aid from the Heritage Council has enabled us to make several expeditions to the island during spring and summer this year to attempt to trap and remove these alien carnivores before irreparable damage is done to the burrow-nesting seabirds,' said Dr Newton.

‘Unfortunately, even as this work was underway, another BirdWatch Ireland member of staff discovered what is almost certainly a mink scat (dropping) on Great Saltee. This island lies a little further, about 5km, off the Wexford coast near Kilmore Quay.

‘BirdWatch Ireland is following up this report and will, if necessary, take appropriate action.'