After a 37-year break from the fashion trend, orcas have recently been spotted wearing dead salmon on their head.

Orcas or killer whales are intelligent creatures known for their ability to pass on certain cultural traditions socially. These trends or traditions amongst the whales can range from whimsical to destructive, as the past few years have seen a rise in orcas conducting targeted attacks on boat rudders.

“Different populations often have distinct dietary specializations that are maintained by cultural transmission, and these ‘ecotypes’ typically have a variety of persistent behavioral traditions that are related to their divergent foraging,” a report into the recent trend of rudder-breaking behavior explains. “Some populations may also develop unusual and temporary behavioral ‘fads’ and other idiosyncrasies that do not appear to serve any obvious adaptive purpose. Understanding the recent boat interactions by Iberian killer whales may benefit from an examination of such ephemeral traditions in other well-studied killer whale populations.”

Another big example of these trends among whales is the dead salmon hat trend of 1987. The fad began with one female orca in the Puget Sound area of the northwest Pacific who began carrying a dead salmon on her nose. The trend spread around the area over the next five to six weeks until orcas from her “K-pod” and two other pods were all sporting dead salmon hats.

Apart from a few whales sporting the trend the following summer, the trend appeared to end here. That is, until recently when orcas belonging to “J-pod” were spotted bringing the trend back.

“Observations indicate they are likely finding plenty of salmon during their stay and may be why they have remained inland so long,” the whale sighting network reports, adding, “Check out this photo of J27 Blackberry sporting a salmon hat.”

Scientists haven’t yet determined the purpose of this behavior. While some of the orcas may have been present during the last salmon hat phase, New Scientist suggests that perhaps their heads simply act as a convenient storage space to save access to salmon for later consumption.

“Killer whales do have fads that come and go, and they’re often most prevalent among certain sex and age classes in the population. Then, over time, they tend to disappear,” director of Bay Cetology, Jared Towers, told Discover. “I’m certainly hoping that’s what happens with this behavior. But it’s been going on for a few years now. So, we’re not quite sure what to expect.”