Scientists say a small group of killer whales could be putting humans and themselves in danger by repeatedly ramming, and occasionally sinking, sailboats. Orcas interacting with boats is nothing new. But scientists say there is something different about the behavior of this group of about 15 orcas off the coast of the Iberian Peninsula near the Strait of Gibraltar, an area they visit each spring, per the New York Times. Since 2020, the group—made up mostly of youngsters, with only two adults in tow—is believed to have been involved in the majority of 200 annual boat-orca interactions ranging from the North African coast to France, according to Alfredo López Fernandez, a biologist at Portugal's University of Aveiro who has studied the interactions.
Damage results in about 20% of incidents, per the Times, noting the critically endangered Iberian orca subpopulation has sunk three boats and "disrupted the trips of dozens of others" since July. They often target the boats' rudders. No one knows for certain why they're doing this. But López Fernandez says it has "nothing to do with aggression." There's no indication that the whales want to hurt humans and usually there's no physical contact. But some believe one particular female orca may have been struck by a boat and began targeting them in what is essentially "defensive behavior based on trauma," López Fernandez tells Live Science. As the biologist tells the Times, "orcas share their culture with their young and with their peers" and learn from imitation.
Some researchers believe the young whales might simply be playing with sailboats, which are quiet and therefore more attractive to orcas than other boats. But whatever the motivation, it's a behavior that puts humans—including four people who had to be rescued from a boat that sank off the coast of Spain this month—and the endangered whales at risk, as sailors become increasingly frustrated by the trend. "Every week there is an incident," researcher Bruno Díaz López tells the Times. Two adults and four juveniles struck a 26-foot boat off the coast of Cape Spartel on Monday, as ABC News points out. Still, "we estimate that killer whales only touch one ship out of every hundred that sail through a location," López Fernandez tells Live Science. (Read more killer whales stories.)