Orc attacks? Killer whales learn of ‘coordinated’ attacks on sailboats, some observers say

Killer whales may be teaching others to attack boats following a series of strikes on sailboats off the coast of Europe, some observers say.

Sailors reported a series of “coordinated” attacks by a group of orcas, including a May 22 strike on a 26ft vessel sailing off Cape Spartel, near the Strait of Gibraltar.

“[Six] orcas arrived, 2 very large adults, 4 smaller ones,” sailor JP Derunes wrote in Orca Attack Reports, a Facebook group dedicated to reporting orca activity. “Both rudders were destroyed and jammed. The boat is to be retired later this week.”

This attack followed a nighttime strike on May 4, when a Swiss yacht named Champagne, which was also sailing through the Strait of Gibraltar, was attacked by three killer whales. They hit her rudder, eventually sinking her, Yacht, a German nautical journal, reported.

At least 15 human-orca incidents have been recorded in 2020, the year the aggressive encounters are believed to have started, according to a study published in the journal Marine Mammal Science. Many of these attacks included killer whales biting or hitting the rudders of sailboats.

No casualties appear to have been reported in the attacks.

The scientists said the spikes in aggression may have been triggered by female killer whales which the scientists named “White Gladis”.

White Gladis is thought to have suffered a “critical moment of agony” like a collision with a boat, which inflicted trauma on the orca, triggering a change in behavior that other killer whales learned to emulate.

The majority of orc-sailor encounters have been harmless.

“In more than 500 interaction events recorded since 2020, there are three sunken ships. We estimate that killer whales only hit one in a hundred ships that sail through a location,” said Alfredo López Fernandez, a biologist at the University of Aviero, at Live Science.

According to a study published in Biological Conservation, a peer-reviewed journal, “sophisticated learning abilities” have been found in killer whales, with imitation being particularly important.