More than 50 pilot whales died on Sunday after they were stranded along a beach on the Isle of Lewis in northwest Scotland. It was the largest mass stranding event in Britain since 2011, marine rescuers say.
The coast guard, police and rescue volunteers found 55 whales — both adults and calves — stranded on the beach on Sunday morning, according to the British Divers Marine Life Rescue charity, which coordinated the response. By the time responders arrived on the beach to administer first aid to the surviving whales, a majority were already dead, the charity added. By 3:30 p.m. local time, rescue teams decided to euthanize the surviving animals “on welfare grounds,” after it was determined that rough waves and shallow beach conditions made it unsafe to refloat them.
Only one of the 55 whales survived, a spokesman for the Western Isles Council, the local government, said in an email. The whale was one of two that had been successfully helped back out to sea. The other whale restranded itself and subsequently died, British Divers Marine Life Rescue said.
It can take a frantic effort to save a whale’s life after it is stranded. Pilot whales — which come from the same family as dolphins and porpoises — can grow to 24 feet in length and weigh up to 6,600 pounds. When beached, they can gradually crush themselves or their blood circulation can be cut off, releasing toxins that poison the animal, marine biologists say.
“They were likely all in the same family, a unit traveling together for decades,” said Daren Grover, general manager of Project Jonah New Zealand, a charity that responds to whale strandings in New Zealand.
The Cetacean Strandings Investigation Program from the Zoological Society of London has logged over 17,000 stranded cetaceans, referring to the class of animals that includes pilot whales, dolphins and porpoises, since its founding in 1990. Last fall, 230 pilot whales were beached on the western coast of Tasmania.
In 2011, roughly 70 pilot whales were stuck in shallow waters off the coast of Sutherland in Scotland. But a quick response led to the successful refloating of 20 of the whales. This time, the rescue efforts faced “major obstacles” from the outset, said Dan Jarvis, director of welfare and conservation at the rescue charity.
“They basically found one of the worst places to strand: in a remote island on a remote beach on a Sunday,” he said.
Roughly 30 miles from the northwest coast of Scotland, the Isle of Lewis is accessible only by ferry or plane. The rescue charity was short on volunteers and equipment was scarce. With no cellphone signal within a two-mile radius of the beach, new communication channels needed to be set up. It amounted to a large-scale coordination effort of more than 50 responders including volunteers, the coast guard, the police and the Scottish Fire and Rescue Service.
The charity said the whale pod might have followed one of the whales ashore after it had difficulty giving birth. “Pilot whales are notorious for their strong social bonds,” the charity’s statement said. “So when one whale gets into difficulty and strands, the rest follow.”
Pilot whales, which are highly social creatures, are the species “most prone” to becoming stranded, according to Scottish Marine Animal Stranding Scheme, or S.M.A.S.S. But the causes of their accidental isolation vary widely, marine biologists say. Whales can be thrown off by sonar or led astray by one sick or injured whale.
On Monday, a team from S.M.A.S.S. was working to collect tissue samples to determine the cause of the stranding. A final conclusion could take weeks or months to determine, Mr. Jarvis said.