Apparently even whales enjoy horsing around.

The reason orca whales have been attacking European ships recently isn’t due to targeted violence, but rather that the enormous mammals consider it a form of recreation, Spanish scientists claim.

While orca pods have been terrorizing ships along Europe’s western coast and inside the Mediterranean — with a recent incident reported in Portugal over the weekend — Renaud de Stephanis, president of Spain’s Conservation, Information and Research on Cetaceans (CIRCE) said this behavior is part of the whales’ “playful” nature.

“What is happening with the Iberian orcas and boats is not an attack in the sense of aggression, predation, or territorial defense,” he told the Daily Mail. 

Orcas have repeatedly attacked sailing ships along the coasts of Spain and Portugal in recent years. Guardia Civil Pontevedra

One pod took down a ship at the Costa da Caparica on Saturday. oceanic_lounge/Instagram

“This interaction is closer to a game than to an attack. They are not mistaking the boats for prey, nor are they defending territory,” he added.

Stephanis, who described the whales as “extremely intelligent” mammals, said rocking ships has become a game “developed by a small subpopulation of orcas” in the region.

The expert surmised that since the orcas are specifically aiming for the ships’ rudders, they enjoy the rocking of the ship and the resistance, treating it as a toy that stimulates them.

Dr. Clare Andvik, a marine mammal expert at the University of Oslo, said the stimulation is ramped up for the whale if the humans onboard the ship try to steer away, creating greater resistance for the orcas to test their might against.

Scientist say the killer whales are purposefully attacking ships not out of malice, but because they find it fun and have made a game out of it. WireImage

The intelligent creatures are allegedly testing their might against the ships, creating fun for the whales but terror for the passengers on board. Carlos Gauna / SWNS

She said the experience amounted to one big game of tug-of-war for the whales.

“Of course from the human perspective this kind of behavior is not at all fun and it doesn’t seem to them like a game as they are getting knocked around,” Andvik told the Mail.  

“And in some cases the rudder can be broken off completely and cause the boat to take on water and eventually sink [which is] fun for the orcas, not for the humans,” she added.

Experts say there have been hundreds of reports of whales interacting with ship between 2020 and 2024. MEEGAN M. REID/KITSAP SUN / USA TODAY NETWORK via Imagn Images

Such was the case on Saturday when a pod attacked a tourist vessel sailing along Portugal’s Fonte de Telha beach and another ship along the Bay Cascais, according to the country’s National Maritime Authority. Nine people were rescued in the incidents.

The Orca attacks have been growing in recent years, with the cases concentrated along the coasts of Spain and Portugal, as well as the Strait of Gibraltar.

Orca Ibérica GTOA, a research group studying the animals, said it has recorded hundreds of “interactions” between orcas and sailing ships in the region between 2020 and 2024.