Science

5 things you think you know about killer whales that are actually wrong

image of a pod of orcas swimming above water
Orcas swimming in a pod in Southeast Alaska. Ron Sanford/Getty Images
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Killer whales, or orcas, are similar to humans in a lot of ways.

They're highly social creatures that travel in pods and communicate in their own special language.

They're also highly curious and sensitive — one orca off the coast of Iceland even adopted a baby pilot whale, for example. Another orca was so traumatized by an encounter with a boat that scientists think she taught other orcas to attack boats, sparking a slew of recent incidents.

But there are a few common misconceptions about these amazing animals. 

Killer whales aren't whales

Killer whales are not actually whales, but dolphins. While they are the biggest members of the dolphin family, they are still much smaller than the biggest whales — orcas can get up to 32 feet long while blue whales can get up to 100 feet long, according to the Ocean Conservancy.

Like other members of the dolphin family, orcas' bodies are built to be aerodynamic, and like dolphins, they're some of the fastest creatures in the ocean, reaching speeds over 30 miles per hour.

The name "killer" whale isn't from killing humans

Orcas are not called killer whales because they're whales that kill humans. In fact, there are no verified accounts of an orca killing a human in the wild.

People in a boat watching an orca whale swim toward them.
Orca whales are curious animals that will approach your boat.  Portland Press Herald / Contributor / Getty Images

These creatures got this name because they kill whales. Ancient sailors originally called them "whale killers" because they would prey on whales much larger than them, according to the Whale and Dolphin Conservation.

Over the years, that got reversed to "killer whale," leading to the misconception that they are a member of the whale family.  

It's not just captive orcas with collapsed dorsal fins

Some orcas develop a collapsed dorsal fin while in captivity, but the phenomenon doesn't just affect captive orcas.

children press against exhibit glass as a large orca with a floppy dorsal fin swims by in the blue water
Young children watch an Orca with a flopped over dorsal fin, at SeaWorld in San Diego, California.  Mike Blake/Reuters

Though more rare, orcas in the wild can get a curved or flopped-over fin on top of their bodies, which typically happens from stress, injury, malnutrition, or dehydration, according to Ocean Wise.

If it doesn't collapse, an orca's dorsal fin can stand up to six feet tall, according to the Whale and Dolphin Conservation.

Killer whales don't eat just anything that comes their way

Contrary to popular belief, orcas are actually pretty picky eaters. 

beach crowded with sea lions and birds with an incoming orca fin and back just offshore
An orca, or killer whale, speeds in a straight line towards the beach before launching itself onto the sand to hunt baby sea lions in Argentina's Patagonian area of Punta Norte.  Enrique Marcarian/Reuters

The whole species does have a wide range of food, including fish, seals and sea lions, dolphins and large whales, squids, and even seabirds, according to WDC. 

But groups of orcas often specialize in a specific prey animal. For example, in the waters off South Africa, orcas have become famous for killing great white sharks and eating just their livers, which are fatty and rich in calories. Scientists believe that two particular orcas, named Port and Starboard, pioneered this strategy and taught it to their podmates.

Individual orcas typically learn to eat what their family eats, and they aren't likely to stray from the pod's standard diet.

Killer whales aren't endangered like many large sea animals

Killer whales live in every ocean in the world, and they have many different subspecies, according to the US National Oceanic and Atmospheric Administration. 

A pod of killer whales swimming in the Antarctic Ocean with ice bergs in the background.
Killer whales exist in every ocean on Earth including the Southern Ocean, aka Antarctic Ocean.  Anadolu Agency / Contributor / Getty Images

While all killer whales are protected under the Marine Mammal Protection Act, there's only one type that is actually endangered. That's compared to many dolphin and whale subspecies that are either endangered or critically endangered, according to the International Union for Conservation of Nature.

The Southern Resident subspecies, native to the Pacific Ocean, has been endangered since 2005, according to NOAA. That's largely because those orcas specialize in eating Chinook salmon, which are in decline all along the Pacific coast.

Also, the AT1 Transient subspecies, native to the Pacific Ocean, was marked as depleted in 2004, according to NOAA. 

Though killer whales may be misunderstood, you definitely shouldn't get a closer look at them. Experts say you should keep your distance and never enter the water when you see an orca.

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Morgan McFall-Johnsen was a science reporter at Business Insider. She covered climate change, weather, Earth sciences, and space, as well as health and medicine, environmental issues, and occasionally archaeology.Email her at mmcfalljohnsen@gmail.com and follow her on X @MorganMJohnsen.Expertise
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Morgan has interviewed astronauts aboard the International Space Station and published exclusive in-depth accounts of early COVID-19 outbreaks on cruise ships.She has appeared on NBC, Scripps News, Sirius XM, C-SPAN, and NPR to discuss climate change, extreme weather, Mars missions, the space race, and far-right extremism. She’s previously written for Backpacker Magazine, Outside Business Journal (formerly SNEWS), and Popular Science.She holds a Bachelor of Science in Journalism from Northwestern University, where she also studied environmental policy and French. She was a 2022 Logan Science Journalism Fellow at the Marine Biological Laboratory and a 2023 Columbia Energy Journalism Fellow.Popular stories
Grace was a politics and business reporter at Business Insider, with a particular focus on topics related to the Department of Government Efficiency. She was previously a homepage and breaking news reporter at BI and an associate producer for BI's breaking news podcast, The Refresh. She has a Master of Science from Columbia University Graduate School of Journalism with a focus on investigative journalism and audio/radio production.