Some things never go out of style. Others certainly do. Then there’s the pocket of culture that routinely makes its resurgence every generation. Children of the ‘80s will recognise the resurgence of retro right now: Arcade machines, synthesisers, salmon hats… the list goes on.

Yes, it may have taken some 37 years but if you weren’t aware: salmon hats are finally back in vogue. At least that is according to recent observations made of orcas within the Northwest Pacific.

For those that may not have received the memo, orcas have started wearing salmon hats again, bringing back – say researchers – a bizarre trend that was first recorded in the 1980s. 

Last month, scientists and whale watchers spotted orcas (Orcinus orca) in South Puget Sound and off Point No Point in Washington State swimming with dead fish on their heads, marking the first time they have been spotted sporting the bizarre headwear in almost 40 years.

It was in the summer of 1987 that the ‘salmon hat’ really took off, when a female orca – spotted wearing the accessory – kickstarted a trend that, within weeks, had spread beyond her pod to two others in what can only be reasonably likened to the ‘perm’ of the cetacean world. Unlike the perm, however, the trend failed to carry through a full season, and by the summer of 1988, the ‘salmon hat’ was a thing of the past.

But it did, however, leave observers with some rather significant learnings of orca behaviour – that the species is just as susceptible to a culture fad as we are.

And, just as fashion seemingly always comes back around within human culture, so too has the trend for salmon hats among orcas. But is it more likely that some orcas are just unwilling to let the 1980s go? As first reported in the New Scientist this month, researchers from the University of Oslo in Norway believe this may just be the case.

“It does seem possible that some individuals that experience [the behaviour] the first time around may have started it again,” said Andrew Foote, an evolutionary ecologist at the University of Oslo in Norway, suggesting that orcas spotted wearing ‘salmon hats’ today may simply be veterans of the trend 40 years back.

The motivation behind the fad is not yet known, though there are a number of hypotheses currently doing the rounds among the scientific communities, including suggestions that hat-wearing “simply feels good”. 

Deeper analysis, however, has looked into the propensity for ‘cultural traditions’ to be passed among the orca species, using the recent trend among Iberian orca for ‘attacking’ boat rudders, stating that some populations of orca develop unusual and temporary behavioural ‘fads’ that serve no obvious “adaptive purpose”.

A report into the recent trend of rudder-breaking behaviour, compiled by the International Whaling Commission, states that “different populations often have distinct dietary specialisations that are maintained by cultural transmission, and these ‘ecotypes’ typically have a variety of persistent behavioural traditions that are related to their divergent foraging.

“Some populations may also develop unusual and temporary behavioural ‘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.”

So why the salmon? Orca researchers’ best current guess is that these salmon fads are linked to high food availability. South Puget Sound is currently teeming with chum salmon, and with too much food to eat on the spot, orcas may just be saving some of the stock for later by balancing them on their heads, notes New Scientist.

It’s certainly a theory that chimes with observations made by the local whale sighting network which writes that “observations indicate they are likely finding plenty of salmon during their stay on the northwest coast of the US state of Washington which may be why they have remained inland for so long.”

With the origins of the ‘salmon hat’ trend obscured by all this uncertainty right now, all bets as to what orca will be wearing next season are off. Although, a krillby hat certainly would make for a fetching wardrobe accessory.

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