Scientists are searching for answers after a series of attacks on boats off the coast of Spain and Portugal — perpetrated by killer whales.
The animals, also known as orcas, have sunk three different boats off of the Iberian coast since 2020, according to Live Science. They’re believed to have attacked many more vessels.
The orcas have learned how to stop a boat after beginning an attack.
The incidents — which primarily involved sailboats — usually involved the creatures striking a ship’s rudder after approaching from the stern. The whales tended to lose interest after successfully stopping a boat’s movement.
University of Aveiro biologist Alfredo López Fernandez has a theory — that the highly social animals have learned this tactic.
López Fernandez believes that one killer whale that suffered a “critical moment of agony” with a boat learned to become aggressive toward them — and taught this behavior to other animals.
“That traumatized orca is the one that started this behavior of physical contact with the boat,” he said.
The expert believes a sole orca began attacking boats — spurred by its own agonizing interaction with one of the crafts.
“The orcas are doing this on purpose. Of course, we don’t know the origin or the motivation, but defensive behavior based on trauma, as the origin of all this, gains more strength for us every day,” he said.
One captain of a vessel that was attacked described an effort that was coordinated by the animals.
“The attacks were brutal. There were two smaller and one larger orca,” Werner Schaufelberger said of the phenomenon, according to Business Insider.
“The two little ones shook the rudder while the big one kept running and then rammed the ship from the side with full force,” he said.
The boat-ramming tactics spread through observation, according to Lopez Fernandez.
“We do not interpret that the orcas are teaching the young, although the behavior has spread to the young vertically, simply by imitation, and later horizontally among them, because they consider it something important in their lives,” he said.
Whale experts caution against entering the water in the event of an orca attack, according to MSN.
In spite of this, a fatal orca attack on a human has never been recorded.
Orcas are understood to be among the most intelligent creatures in the animal kingdom.
The creatures have the second-largest brains among marine mammals, according to Phys.org.
This article appeared originally on The Western Journal.