Sailors Trade Tips on How to Stop Orca Attacks on Boats

The first time orcas appeared near his catamaran, Florian Rutsch was surprised, but prepared.

Like many venturing around the Iberian Peninsula, Mr. Rutsch had browsed Facebook groups, Telegram chats and other online platforms where sailors have been swapping tips on a relatively recent phenomenon: How do you get orcas to leave your boat alone?

In May, when the crew of his catamaran, which he charters for high-end voyages and retreats, encountered an orca group while crossing the Strait of Gibraltar, he tried some of those ideas. He scattered sand in the water, which some sailors thought could act as a deterrent (unsubstantiated). Then he slammed the engine into full throttle, moving away from the group (advice supported by the Spanish government).

The orcas left them alone. But his second encounter with the animals in November was less civil.

This time, to deter them, the crew also tried another idea that had been passed along: booming a curated playlist of heavy metal — titled “Metal for Orcas” — through an underwater speaker. But the animals had moved quickly, targeting the rudder and disabling the boat’s steering. The crew had to call for help, and eventually Spanish rescue authorities arrived and towed the vessel to port.

“It is scary” said Mr. Rutsch. “No one knows what works, what doesn’t work.”

‘It’s the talk of the town.’

Since 2020, orcas — apex predators that are the largest members of the dolphin family — have been disrupting the journeys of boats along the coastlines of the Iberian Peninsula, causing enough damage to a handful to sink them. Researchers don’t know why.

Online, some have been charmed by the schadenfreude of the orcas striking back at their yacht overlords, but biologists say it’s likely that the curious animals have simply learned a new way to play with boats.

It is less charming for the skippers and boat owners navigating some of the busiest water lanes in the world in floating homes that can be costly to repair. A small percentage of sailing boats have been affected, according to researchers, who are still testing methods that could minimize the interactions.

But until a tried-and-tested solution is found, sailors are gathering, online and in person, to compare notes. One Facebook group, with 59,000 members, details accounts of interactions, while in another, users talk tactics. In Telegram chats, they ask for feedback on detours to avoid what has been called “orca alley.”

“People are more informed,” said Rui Alves, a former sailor who founded Orcas.pt to help sailors connect and discuss the issue. Mr. Alves says he has been surprised at the site’s popularity — when he started it in October 2022, about 10 people joined. Now, there are almost 2,000.

“We have the local sailors, Portuguese and Spanish, and we have these sailors coming from the U.K. to cross the Atlantic,” he said.

More established groups like the Cruising Association, a Britain-based group for sailors, have also been tracking accounts from crews and collaborating with researchers to offer up-to-date information. “Sailors working together with appropriate scientists is the best approach to finding a solution,” Paul Lingard, a spokesman for the group, said in a statement.

“It’s the talk of the town in the sailing community,” said Emma Gore, a yacht sailor who found advice from Facebook groups helpful when she encountered an orca off the coast of Morocco. “Everybody is a bit on edge.”

Sail away, sail away, sail away.

Do any of the deterrents posed by sailors work? Researchers are skeptical that scattering sand or changing the color of a boat’s hull (avoiding black is one suggestion) do much. They also caution that some of the suggested methods — like throwing firecrackers into the water or using pingers, devices that transmit high-pitched signals underwater — could hurt the animals, which are considered endangered.

There are plans, according to the Cruising Association, to test out an acoustic device that could deter orcas from approaching without causing harm to them. And biologists are tracking the animals, some working with the Spanish government to understand how adjusting boat movements could minimize the chance of interactions.

For now, researchers and authorities say, the only real solution is to sail in shallower waters and move away as fast as possible during an orca encounter.

“The solution is to leave the area,” said Renaud de Stephanis, a biologist and coordinator for the nonprofit research group CIRCE. He’s part of a project that is satellite-tagging orcas to better track their movements as they chase tuna along the coastline. Mr. de Stephanis said it was clear that the orcas had learned how to break rudders, and research this year suggested that not stopping a boat could minimize the animals’ opportunities to do so.

Mr. Alves, the Orcas.pt founder, said, “I think long term it will be that we know where they are — and we avoid that area.” Many sailors are already taking that advice to heart and say they will stop sailing through any orca lanes until a solution is found.

“I do worry that people will resort to more drastic measures if we don’t find harmless solutions soon,” said Mr. Rutsch, the German sailor. Detours to avoid the orcas could add days, or even weeks, to a journey, and shallow waters open boats up to other dangers like underwater rocks and fishing nets.

“No sailor really wants to hurt any orcas,” Mr. Rutsch added. “That is the big conundrum here.”

He was tense during a crossing of the Strait of Gibraltar last week, he said, and took a flare and a foghorn in case of another encounter.

“Luckily this time,” he said. “We were only briefly scared by some dolphins.”