Why orcas wear dead salmon as 'hats' remains a mystery, scientists say

In what may seem like a call-back to 1980s whale culture, a resident orca off the coast of Washington state was recently spotted sporting a dead salmon on its head. 

The phenomenon was first documented in 1987 when whales from three separate pods were seen wearing salmon on their heads, like a human wears a hat.

But scientists never understood why, and experts are still scratching their heads as they contemplate the most recent incident, documented in October. 

The director of the University of British Columbia's Marine Mammal Research Unit, Andrew Trites, said there's no obvious reason for the behaviour.

"Maybe it's to impress another member [of the pod]," he told CBC Radio West guest host Brady Strachan. "Maybe they just like the smell of dead fish."

Radio West6:24Orcas off the coast of BC have been seen wearing dead salmon on their heads like hats

Orcas off the coast of BC have been seen wearing dead salmon on their heads like hats

But he and his colleagues suspect it's playfulness.

"It's probably being done by young animals and is probably something [that] others may catch on and do because they're very good at mimicking … in the same way that young kids can pick up tricks from others, sometimes to the disapproval of their parents."

Trites added that it wouldn't be to carry the food, because the salmon wouldn't be secure. Furthermore, orcas have other ways of carrying food — such as underneath their pectoral flipper.

Social symbol

The recent sighting was in Puget Sound, Wash., on Oct. 25. The person who saw it grabbed a photo and sent it to the Orca Network, a non-profit that tracks whale activity.

"Check out this photo of J27 Blackberry sporting a salmon hat, taken from Point No Point! May they continue to find lots of fish during their stay here in inland Puget Sound," reads a blurb accompanying the photo in the organization's recent newsletter. 

Howard Garrett, who co-founded Orca Network in 2001, said while the behaviour is a mystery, he believes it's a form of communication. Although he's not a marine biologist, Garrett has a degree in sociology and has been observing orcas since 1981.

"Orcas are the most socially bonded mammals known to science, they stay in their families and their extended families for life," he said.

"They're completely social, so this is some sort of social communication. And what it indicates is that they are using the fish as some kind of symbol. A symbol of what, I don't know."

Feast of fish

Both Trites and Garrett say the behaviour could be related to the abundance of fish in the area.

The J Pod was in inland Puget Sound continuously for more than a month this fall, feasting on fish thanks to a huge chum salmon run, Garrett said.

"Maybe it was celebrating that there are just so many fish [around that] we can play with them."

Southern resident killer whales were listed as endangered in 2005, due in part to a lack of available food.

Trites interprets the sighting as good news from an orca population that has been struggling.

"Here we've got some animals that are playing with their food. That tells me they must have full bellies and they must have time on their hands."

The Current9:47Orcas visit downtown Vancouver for an ‘afternoon snack’

A family of orcas wowed a passenger ferry in Vancouver's False Creek this week. We hear why researchers are also delighted by their unusual adventure into the heart of the city.

Fashion throwback

The single sighting of this strange behaviour has experts in the field recalling the story of salmon hats from the 1980s.

Erin Gless, executive director of the Pacific Whale Watch Association in Washington state, says the story behind the salmon hats dates back nearly 40 years.

"I wasn't here for the first round of the 'salmon hat' trend, but apparently in 1987, a female from K Pod started carrying a dead salmon on her head," she told CHEK News. 

"Within a few weeks, the other two pods also exhibited the behavior, which served no known function and fizzled out after the year."

Monika Wieland Shields, director of the Orca Behavior Institute, speculates that this recent sighting was a one-off and not the return of an aquatic fashion statement.

"This was a real trend in the 80s where, over the course of a summer season, southern residents carried dead salmon on their heads, one of several whale 'fads' that have come and gone over the years," she told CHEK News.

She said in this case, it's more likely that the orca was simply hunting, and it was just a lucky moment caught on camera.

"In my opinion, it's a stretch to say it was a salmon hat, and an even greater stretch to say the fad is back off a single photo," Shields said.