Despite the threatening-sounding name, killer whales aren't really something humans should be afraid of — at least not in the wild.
Orcas have been having a moment thanks to a critically endangered subpopulation of orcas targeting and, in three cases, sinking boats off the coast of Spain and Portugal.
The encounters prompted tongue-in-cheek memes portraying orcas as revolutionaries fighting back against environmental destruction brought about by humans.
But orca experts say the animals are most likely just engaging in playful behavior, not organizing a revolution.
Generally speaking, killer whales do not pose much of a threat to humans.
In the case of the boat encounters near the Iberian Peninsula, no humans have been harmed. In fact, there are no documented cases of an orca intentionally harming a human in the wild.
Hanne Strager, a Danish biologist and whale researcher, said people off the coast of Norway have been swimming in close proximity to killer whales for decades.
"The killer whales do not seem to be at all interested in people. They are interested in food, which for them in that area is herring," Strager, who co-founded the Andenes Whale Center in Norway, told Insider. "I think they just think humans are some odd thing, certainly not food, and not really anything that they are bothered by."
That's exactly why the orcas do not attack — they do not see people as food.
"When you look around the world, the different types of populations have specialized in eating different types of prey," said Andrew Trites, director of the Marine Mammal Research Unit at the University of British Columbia, adding that some orca populations primarily eat fish, while others eat marine mammals.
"They stick to what they know, and humans have never been part of their diet," he told Insider, noting the Iberian orcas primarily eat bluefin tuna. Trites added that he thought it would be unlikely for an orca to mistake a human for a seal given the whales' intellectual abilities.
The Iberian population members targeting boats also do not seem to be interested in humans, Strager noted. The encounters typically involve the orca approaching the boat from behind and striking the rudder, sometimes until it is broken and the boat is immobilized.
One crew member who was on a vessel that was sunk by the whales told Strager that as soon as the boat began to sink, the orcas lost all interest in it and left. They don't seem to be interested in what's on board the vessels, just the vessel itself.
Strager and Trites are among the experts who think the most likely explanation for the behavior is that the orcas are playing. Strager compared it to the way a human might play with bubble wrap by popping it. In other words, the orcas may just view the boats as big toys.
Orca-caused human deaths all have one thing in common
There have been four recorded orca-caused human deaths — along with hundreds of instances of killer whale aggression towards humans — but only in captivity.
Three of these deaths involved the same wild-caught orca, named Tilikum, who was a focus of the 2013 documentary "Blackfish." Tilikum was involved in the deaths of a trainer at a park in Canada, a trainer at SeaWorld Orlando, and a man who was believed to be trespassing at the Florida park.
However, Strager said it's impossible to draw any conclusions about wild orcas based on the behavior of captive orcas, as they are in such an artificial environment.
While orcas have not been documented attacking humans in the wild, that does not necessarily mean they are safe to swim around, both Strager and Trites said. As with any large, wild animal, there's an inherent danger involved, just as there would be if a human approached a herd of elephants.
And even if the orcas aren't trying to attack people, the boat encounters are still dangerous, as is a boat sinking in the ocean with or without an orca present.
Researchers have also expressed some concern over the perception that orcas are attacking people.
"If we become so frustrated with their behavior that we think they don't deserve to be protected anymore, then it is a risk for the whales," Strager said, noting the orca population near the Iberian Peninsula is severly endangered.
