Why are orcas ramming boats? They might just be bored teenagers

Off the Iberian Peninsula, a group of orcas have become famous for sinking several vessels—the latest just weeks ago. The predators’ motivations for this odd behavior, which began in 2020, has sparked wild speculation: Are they having fun, avenging humans, or doing something else entirely? Now, experts say they finally know what’s going on. 

In a newly released report, scientists with the International Whaling Commission believe this pod of around 15 animals are most likely mischievous “teenagers." 

To come to this conclusion, the researchers analyzed online footage of orcas engaging in aggressive behaviors, such as hunting. They also studied videos of the animals playing with things like their food, jellyfish, and kelp, and saw no sign of hostility. (Learn five ways orcas are surprising scientists.)

“They approach [a boat] calmly and gently, and it looks like they're playing. They push the rudder gently with the tip of the nose,” says Alex Zerbini, the commission’s scientific committee chair and a senior scientist at the University of Washington in Seattle. “The behavior is very, very different from being aggressive.”

“They don't really know that their playfulness is causing harm… it’s not intentional,” Zerbini says. “When we are teenagers, we do things that maybe we wouldn't do as an adult. We’re more courageous,” he says. 

Rob Lott, campaign coordinator at Whale and Dolphin Conservation, a U.K.-based nonprofit, agrees with this theory.

“This is a solid conclusion that what we’ve witnessed is just a form of play behavior, as alarming it is for the mariners on board,” says Lott, who wasn’t involved in the report. 

The young and the restless

Found worldwide, orcas are incredibly intelligent hunters, and, depending on their habitats, populations specialize in different kinds of prey.

For instance, Australian animals work as a team to kill blue whales, the largest animals on Earth; Antarctic orcas use waves as a tool to flush seals into the water; and notorious pair in South Africa dine on great white shark livers.

The Iberian Peninsula population, which has a specialized diet and feeds mostly on bluefin tuna, is listed by the International Union for Conservation of Nature as critically endangered, with fewer than 40 individuals left. (See 13 of Nat Geo’s favorite photos of orcas.)

One explanation for why the orcas began sinking boats could be an abundance of their primary food staple. Once endangered because of overfishing, Atlantic bluefin tuna has recently bounced back thanks to the enforcement of sustainable fishing quotas.

“Now that the bluefin tuna has recovered, it makes sense that not only the whales are well nourished, but they have more time on their hands and that's why they are engaging in these more social activities,” Zerbini says.

Seeking play, not vengeance

The report also stresses that describing these encounters as attacks—or pushing the idea that orcas are taking revenge against people—is not only inaccurate but could be harmful to the rare animals. In August 2023, a vessel crew crossing the Strait of Gibraltar fired projectiles at the orcas, which conservationists reported as a crime against the protected species.

“Revenge is clearly not their motivation here,” Lott says, adding that there are no recorded instances of wild orcas killing a person, despite “humans, over the decades, giving them ample opportunities for revenge,” such as hunting them. 

That said, being rammed by an orca—even playfully—can be frightening, which is why experts recommend boats navigate around known orca hot spots in the Strait of Gibraltar, or move away immediately if an animal approaches and let other boats in the area know of their location.

Scientists also plan to experiment with non-harmful measures to prevent the cetaceans from damaging rudders, such as towing dinghies as a decoy or modifying the rudder.

They will also test using a sudden, unexpected noise to deter them. “We've seen that, if you trigger this startle reflex, the animal will move away,” says Thomas Goetz, an animal bioacoustics researcher at the University of St. Andrews in Scotland. 

Lott is also confident this teenage trend will fizzle out—and may have already started to, with fewer incidents in 2024. In the 1980s, orcas in Puget Sound, Washington, started carrying dead salmon on their heads like a hat. “That fad disappeared as quickly as it appeared,” he says.  

In the meantime, Lott recommends that people “keep a cool head and take the appropriate advice—and hopefully all will be well for both sailors and orcas.”