Scientists Say They Know Why Killer Whales Are Attacking Boats Off the Coast of Spain

Scientists have said they believe they know why killer whales started attacking boats off Spanish coast. Having assessed footage of some of the attacks, researchers said they were carried out by two or three young animals.

They noticed two of the killer whales were seriously injured—which may have prompted their behavior. Speaking to Spanish daily newspaper El Pais, researchers say it is unclear whether the killer whales, also known as orcas, were injured before or during their encounters with the boats, but that the killer whales may have felt threatened.

Alfredo López, a biology professor at the Coordinator for the Study of Marine Mammals (CEMMA), told the newspaper: "It's not revenge. They're just acting out as a precautionary measure." He said the killer whales did not appear to have a premeditated plan to cause damage to the boats, "even if eventually damage is done."

"Our interpretation is that they don't have the slightest intention of attacking people."

News reports of orcas attacking boats off the coast of Spain emerged at the start of September, with encounters having started as early as July. Sailors were reporting orcas ramming their boats and yachts. One Spanish naval yacht lost part of its rudder after several orcas attacked it.

In an interview with the BBC, a Scottish yacht owner Graeme Walker, whose vessel was attacked for 45 minutes early on September 22, described his encounter with three orcas: "The boat would literally spin through 90 degrees when the animals came in. It was as pronounced as that. When they actually bit on the rudder and started shaking the rudder the wheel was spinning from side to side. You could not have touched it. You would have broken your arms."

That same day, Spain's Ministry of Transport, Mobility and Urban Agenda announced sailing vessels that were 49 feet or less were banned from sailing between Cabo Prioriño Grande and Punta de Estaca de Bares, where the killer whale attacks had taken place. This was as a preventative measure to protect people on board and the killer whales.

"Interactions with killer whales have affected, above all, medium-sized sailboats, with a length equal to or less than 15 meters (49 feet)," a statement from the ministry said. "All the encounters with the killer whales took place between 2 and 8 nautical miles from the coast and the sailing speed ranged between 5 and 9 knots, either exclusively under sail or sail and motor."

Justin Crowther, a British sailor whose yacht was attacked and had to be rescued, told El Pais that after docking he realized how close the orcas had come to overturning the boat. "I have sailed in Australia, Tahiti, Canada... all over the world, and I had seen orcas, but none had ever gotten this close," he told the newspaper.

López says that while this increase in killer whales attacking boats seems extreme, the encounters are still relatively rare. He said only 20 percent of orca sightings from yachts had reported damage or trouble. "It might sound as if all the boats are being damaged, but that is not the case," he said.

killer whale
Stock image showing a pod of killer whales. Researchers in Spain say the recent orca attacks on boats were related to injuries sustained by the at least two of the whales. iStock