A pod of killer whales is accused of 'orchestrated' attacks on boats, terrifying the sailors and baffling scientists

• A series of aggressive actions by orca whales along the coast of Spain and Portugal has left scientists baffled.
• Many sailors have sent distress calls after orcas have left their boats seriously damaged and crew members injured in the past two months, as detailed by The Observer.
• A crew member of a 46-foot delivery boat described being surrounded by nine orcas that rammed the boat for an hour, causing it to spin 180 degrees and the engine to shut down.
• Experts told The Observer that the behavior was highly unusual and that it was unlikely — though not impossible — the orcas were mounting deliberate attacks.
• One researcher told The Observer that she believed it could be signs of stress, with orcas in the crowded Gibraltar Strait competing at times with fishing boats for fish.

Killer whales are said to be ramming and harassing sailboats traveling along the Spanish and Portuguese coasts in a series of incidents that have left scientists baffled.

Sailors have sent numerous distress calls in the past two months, detailed in The Observer, with reports of crew members sustaining bruises and at least one boat having to be towed away because of serious damage.

In one instance, a crew member on a 46-foot delivery boat described being surrounded by nine orcas off Cape Trafalgar in Spain. The crew member, Victoria Morris, said the whales, which can weight up to 6 tons, rammed the boat continually for one hour, causing it to spin 180 degrees and the engine to shut down.

Morris told The Observer that the July 28 incident felt like a "totally orchestrated" attack.

"The noise was really scary," Morris said. "They were ramming the keel, there was this horrible echo, I thought they could capsize the boat. And this deafening noise as they communicated, whistling to each other. It was so loud that we had to shout."

The orca pod had left by the time help arrived, but the boat still had to be towed to a nearby town called Barbate. There the rudder was found to be damaged, with teeth marks along the boat's underside.

Several days earlier, a man was motor sailing alone off Barbate when he heard a sound "like a sledgehammer" and saw his wheel "turning with incredible force." Nick Giles told The Observer that his 34-foot Moody yacht spun 180 degrees as he felt it lift up.

"The boat lifted up half a foot and I was pushed by a second whale from behind," he said. While the sailor was resetting the cables, he said, an orca hit again, "nearly chopping off my fingers in the mechanism."

In a similar instance, a crew member from another delivery boat near Barbate told the port authority that the force of the orcas hitting the ship "nearly dislocated the helmsman's shoulder and spun the whole yacht through 120 degrees," according to The Observer.

Researchers cited by The Observer said it was not unusual for orcas, which are highly social and curious animals, to follow boats or even playfully interact with them. It is unnatural, however, for them to become aggressive, and experts told The Observer it was unlikely — though not impossible — that the orcas were mounting deliberate attacks.

"For killer whales to take out a piece of a fiberglass rudder is crazy," Rocío Espada, who works with the marine biology laboratory at the University of Seville and has observed this population of orcas in the Gibraltar Strait for years, told The Observer. "I've seen these orcas grow from babies, I know their life stories, I've never seen or heard of attacks."

Ruth Esteban, who has also studied the Gibraltar orcas extensively, told The Observer that it was unlikely multiple orca groups would display such unusual behavior and that a single group was therefore most likely responsible.

Espada believes said the ramming could indicate stress, as Gibraltar orcas are endangered and often compete with fishing boats for food in the noisy and polluted waters in the busy strait.

Ezequiel Andréu Cazalla, a cetacean researcher who also spoke with The Observer, described the Gibraltar Strait as "the worst place for orcas to live."

Another researcher, Pauline Gauffier, told The Observer that competition for bluefin tuna in particular had led the local orca population "to the very edge, with only about 30 adults left."

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