An Iberian killer whale interacts with the rudder of a sailboat near the Strait of Gibraltar. (Renbaud De Stephanis/IWC via Washington Post)
Hundreds of dangerous boat-ramming incidents over the past five years have cast orcas as deep-sea villains plotting to take back the ocean.
But the killer whales causing mayhem off Europe’s Iberian Peninsula might actually just be bored teenagers - at least, that’s the leading theory among a group of more than a dozen orca experts who have spent years studying the incidents.
Since 2020, members of a small group of killer whales have rammed into at least 673 vessels off the coasts of Portugal, Spain and Morocco - causing some to sink. The Spanish and Portuguese governments responded by tasking a group of experts with determining what was causing the whales to strike rudders, which are used to steer ships, and how to stop it.
The group, which includes biologists, government officials and marine industry representatives, on Friday released a report outlining their hypothesis: The orcas just want to have fun, and in the vast - and rather empty - open waters, the boats’ rudders are a prime toy.
"This looks like play,” said Naomi Rose, a senior scientist at the Animal Welfare Institute who was part of the working group. "It’s a very dangerous game they’re playing, obviously. But it’s a game.”
In most cases, the scientists found, the orcas approaching the vessels come from a group of about 15, mostly juvenile, whales. They typically approach slowly, almost as if to just bump the rudders with their noses and heads. But even young orcas average between 9 and 14 feet long, so the rudders would often get damaged or destroyed when the whales touched them, said Alex Zerbini, who chairs the scientific committee at the International Whaling Commission, a global body focused on whale conservation.
"There’s nothing in the behavior of the animals that suggests that they’re being aggressive,” said Zerbini, who is also part of the working group. "As they play with the rudder, they don’t understand that they can damage the rudder and that damaging the rudder will affect human beings. It’s more playful than intentional.”
Though orcas are known for their whimsy antics - like using jellyfish, algae and prey as toys - the researchers believe their playfulness has reached new levels in the Iberian Peninsula because of the rebound in the bluefin tuna population, their main source of food. In past decades, when orcas faced a tuna shortage, much of their time was spent trying to hunt down food. But once the tuna population bounced back, whales suddenly "have all this leisure time on their hands because they don’t have to eat every fish they find,” Rose said.
It’s not yet clear why the orcas are attracted to rudders or how they became fascinated by them in the first place. Still, Zerbini said it could have started with one curious, young killer whale that was perhaps enthralled by the bubbles surrounding a moving ship.
"Maybe that individual touched a rudder and felt that it was something fun to play with,” he said. "And, after playing, it began propagating the behavior among the group until it became as widespread as it is now.”
In other words, it became a ridiculous fad - not unlike, say, the viral Tide pod or cinnamon challenges.
It wouldn’t be the first time that killer whales mimicked a particular craze. In the past, some populations have taken to wearing dead salmon as hats or playing games of chicken, Rose said. And, just like human fads, the trends have a tendency to make comebacks years later, she added.
"My guess is that juveniles who see their older siblings or parents wearing salmon hats or doing some other fad sometimes remember these things as adults and think, ‘This is funny. Let’s do it again,’” she said. "These animals are cultural and sophisticated thinkers, and they’re just incredibly social.”
Orcas, Rose said, are similar to people in many ways. For instance, each population has a particular culture, language and food staple. Orcas and people also mature at a similar pace and, much like humans, female whales do so faster than males.
When it comes to the rudder bumping, Rose said, most of the whales involved are male juveniles and teens, meaning they are between the ages of 5 and 18. Fully grown males - over the age of 25 - are not participating in the antics. And while some adult female whales have been spotted at the scene of the incidents, "they seem to be just sort of keeping an eye on their kids, who are doing the actual playing,” she added.
For sailors though, the practice is no game. Rose said she worries about frustrated mariners launching flares or other devices to deter whales. Not only could those measures deafen or harm whales, they might backfire by "making the game even more fun for them,” she said.
"The more dangerous it is for the orcas, the more thrill they seem to get out of it,” she said.
So what’s a better way to stop the boat-ramming? According to researchers: taking away the orcas’ toys - or, at least, making them less fun to play with.
The working group proposed several methods that will be tested this summer, Zerbini said. One involves replacing rudders’ typically smooth surfaces with abrasive or bumpy materials. They will also test a device that makes banging sounds around vessels and have suggested that boats hang rows of weighted lines, which orcas dislike.
"We don’t want to see more boats being sunk and we don’t want to see people in distress,” Zerbini said. "But we also don’t want to see the animals being hurt. And we have to remember that this is their habitat and we’re in the way.”
