Orcas have attacked and sunk three boats off the coast of Europe recently.
Alarmingly, experts say the orcas are teaching others how to sink boats.
In the latest incident, three orcas attacked a yacht on May 4 in the Strait of Gibraltar.
“There were two smaller and one larger orca,” skipper Werner Schaufelberger said.
“The little ones shook the rudder at the back while the big one repeatedly backed up and rammed the ship with full force from the side.
“The two little orcas observed the bigger one’s technique and, with a slight run-up, they too slammed into the boat.”
Spanish coast guards rescued the crew but the boat sank as they were towing it into port.
Two days earlier six orcas attacked another sailboat in the same area.
That boat did not sink but was disabled.
Greg Blackburn was sailing that ship.
“We took a knock to the rudder, and at first I thought we had just rolled down a wave and got a bit of resistance,” Blackburn said.
“Then we had a second one, which caused us to jump around, and then the third one we were trying to turn up into a wave, and the rudder went ‘no you’re going the other way’.
“At that point, we were like ‘there’s definitely something down there’.
“After that was when we got the first sighting of them.
“Once the main pod turned up it looked like there was a matriarch with a calf.
“Thought ‘oh dear’ when I saw them.
“There’s not a lot you can do at that point.
“After reading reports and knowing what has been going on, just thought we were in for a ride now.”
Alfredo López Fernandez, a biologist at the University of Aveiro in Portugal, said:
“The reports of interactions have been continuous since 2020 in places where orcas are found, either in Galicia or in the Strait.
“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.
“In more than 500 interaction events recorded since 2020 there are three sunken ships. We estimate that killer whales only touch one ship out of every hundred that sail through a location.
“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.