Dr. Lance Barrett-Lennard preparing to deploy a hydrophone from a boat

Sounds All Around

Killer whales look so elegant when they travel along the surface, you might never guess that they can be loud and chatty. But underwater, they make a whole lot of interesting noise.

B.C. killer whales mainly live in darkness - sunlight doesn't reach very far down into the ocean in this part of the world. So to navigate and talk to each other, killer whales use sound.

Sound waves travel five times faster in water than they do in air, and they travel a lot farther too. That’s why loud noise, or noise pollution, from boats or sonar testing can be so harmful to these animals.

Unlike residents, transient killer whales hunt in virtual silence so they can sneak up on their prey!

A killer whale swimming by a Steller sea lion haulout

Calls		When killer whales want to introduce themselves or announce their presence in an area, they send out a call. It’s their way of saying, “Hi! I’m here! I'm part of Mary's matriline.” These squeals, squeaks and screams are most commonly heard by scientists researching killer whale languages.
Clicks		Much like bats, killer whales send out a sound signal that bounces back to them if it hits something. This animal version of sonar is called echolocation. For killer whales, the sound is a long series of clicks, which scientists call a click train.
Whistles		Killer whales can make cool sounds that sound like whistles. These are used to socialize with other killer whales when they’re close together.

Killer whales have dialects, just like we do. The sounds they use to talk to each other aren’t genetically passed down from generation to generation – they’re learned. And just as our languages change with time and distance, killer whale dialects differ from group to group. By analyzing the similarities in the calls of different whales, scientists can figure out how closely they’re related.

In B.C., each killer whale ecotype (resident, transient, or offshore) makes different types of sounds. This is unusual for mammals – most mammals in the same species make very similar sounds to communicate with each other. In fact, unlike birds, most mammals can't learn or produce complex sounds. The exceptions are toothed whales, like killer whales, and humans.

Residents		Resident killer whales are talkative. They chat a lot, whether they’re chasing down a school of fish, traveling, or just hanging out. Killer whale pods that are closely related usually have similar dialects.
Transients		Transient killer whales sound very different than resident killer whales. They don’t make as much noise as the residents do. Because marine mammals can hear their clicks and whistles, transients need to be silent to sneak up on their prey. And unlike residents, they all sound very similar to each other. Scientists think that because transients don’t travel with the same group all their lives, they don’t have a chance to develop their own dialects.
Offshores		Offshore killer whales are very chatty, like residents. They have completely different calls than the residents or transients, but they haven’t been studied as closely yet.