BURTONPORT, Ireland, Nov. 7 (UPI) -- The deaths of 33 whales beached off the northwest coast of Ireland were puzzling scientists Sunday.

The whales were found on Rutland Island near Burtonport in County Donegal Saturday, the BBC reported.


They are believed to be the same group spotted in the Inner Hebrides of Scotland at the end of October.

Simon Berrow of the Irish Whale and Dolphin Group said it was one of the bigger mass deaths of whales ever to occur in Ireland, and he fears Royal Navy sonar equipment could have played a role.

"Thirty or 40 pilot whales were spotted off the Inner Hebrides at South Uist last week," he said. "It looked like they were going to strand. It was bad weather. They were not seen again."

Berrow said naval forces had been operating near South Uist and had moved away.

A Royal Navy spokeswoman, however, said that when the whales were spotted near South Uist, the nearest naval vessel was 50 miles away. At that distance, she said, the sonar could not have affected them.

A team from the Galway-Mayo Institute of Technology went to the scene off Donegal to investigate.