Four of thirteen pilot whales that stranded overnight on a beach in Co. Donegal have died. The other nine have been successfully re-floated by a local rescue effort that involved up to 100 people at its peak according to reports.

The whales were spotted on Ballyness beach at Falcarragh, Co Donegal at 8am this morning.

“It’s not something you want to see everyday,” local councillor Seamus O’Domhnaill told reporters.

“The difficulty was that their intention seemed to be to want to come back in,” he said. “They were barely alive but once they were in the water they came around and were in a better condition when we started to guide them to sea.”

The stranding of large groups of pilot whales around our coasts is unusual, but not unprecedented. One of the highest profile cases in recent years was a group of 33 pilot whales that live stranded and subsequently died on Rutland Island, also in Co. Donegal, back in November 2010.

The precise reasons for these stranding events is unknown, but speculation is always rife following an incident. Theories proposed in the past range from healthy whales following a sick member of the group in to shore, to offshore naval exercises, to a potential side-effect of seismic offshore surveying.

The Irish Whale and Dolphin Group (IWDG) stressed that even with plenty of help, experience and specialised equipment like floatation pontoons, it is extremely difficult to successfully refloat animals this size. Once they are removed from the neutral buoyancy of the water for any length of time their own bodyweight becomes a serious issue, and can cause irreparable crushing injuries to internal organs.

There is a strong possibility that the rescued animals will re-strand further along the same beach or at another nearby location.

According to the IWDG, who monitor cetacean stranding events around the country, this is the 13th stranding reported from Donegal in 2014, and the second live stranding. A harbour porpoise Phocoena phocoena live stranded and was refloated at Lough Foyle on 25 February. Another recent stranding that attracted a lot of media attention was that of a freshly dead northern bottlenose whale, Hyperoodon ampullatus, which was found at Cruit Island, Co. Donegal on 23 March this year.