Donal Hickey: Ireland's battle against invasive species

'With ocean waters warming, we’re going to see more coming on their own steam'

The Chinese Mitten Crabs can cause a lot of damage to soft banks through burrowing, thereby increasing erosion.

How so many strange creatures continue to arrive here is a constant source of wonder. The Chinese mitten crab has made the long journey and has been reported three times in Ireland, all in Waterford Harbour, the latest being in January of this year.

Like other invasive species, it could have come here by sea, either in ballast water or by hitching a lift on a ship’s hull. Some animals are brought in as pets, but that’s most unlikely in this case.