Thirteen dolphins were killed after being caught in trawler nets off the west coast of Ireland, post-mortem examinations have revealed.
The dolphins, a protected species, were washed up in Co Mayo over one week at the end of January, many of them with scarring and rips to fins consistent with being entangled in fishing gear. Some of the dolphins were washed up on Achill island at Keem bay and Keel.
The Department of Arts, Heritage and the Gaeltacht commissioned a specialist cetacean veterinarian team to carry out post-mortem examinations on five of the dead mammals.
The results showed evidence that trawlers had caused the deaths, with examinations showing net marks on the dolphins' fins and tail flukes and body wall, bleeding in the lungs and stomachs with recently ingested prey.
Jimmy Deenihan, minister for arts, heritage and the Gaeltacht, has called a meeting with the Department of Agriculture, Food and the Marine to see what actions can be taken to reduce risks to dolphins.
The dolphins are believed to have been caught in nets as they fed on shoals of fish around the trawler.
Simon Coveney, agriculture minsiter, said: "In addition to our own boats, many other European fleets operate in Irish waters, an area that is intensely fished. On the basis of these examinations, it is not possible to determine which of these fleets might have been involved in this incident."
The post-mortem examinations were undertaken in Athlone at the regional veterinary laboratories of the Department of Agriculture, Food and the Marine.
Common dolphins are one of 24 species of cetacean that occur in waters off Ireland and are subject to strict protection under national and international legislation.
Dr Simon Berrow, head of the Irish Whale and Dolphin Group (IWDG), said he believed similar incidents are going unrecorded: "We are concerned that significant bycatch of dolphins is occurring in Irish waters by foreign fleets with no observers monitoring and quantifying these events to ensure they are not having significant impact on dolphin populations, which are all protected."