Though researchers have some best guesses, nobody seems to know for sure why exactly a killer whale in Washington state was wearing a dead fish as a hat.

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 like hats.

An especially popular killer whale put a dead fish on his head, in a throwback to a fashion last seen in the 1980s.

A group of orcas off the west coast of North America has brought back a bizarre fashion trend not seen since the late 1980s: wearing a single dead salmon on their heads as if it was a hat. Experts are at a loss to explain why orcas would want to wear fish in the first place,

The fashionistas of the ocean have spoken, and it’s official -- salmon hats are making a comeback among orcas.

Sometimes, nature surprises us with behavior that feels more like a quirky human trend than an animal instinct. That’s exactly what’s happening off the Pacific Northwest coast, where orcas are once again donning “hats” made from dead salmon.