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When behavioural ecologist Michael Weiss spotted a Salish Sea orca holding a green object in its mouth, he chalked it up to typical cetacean shenanigans.
“Because whales do weird things,” he shrugged. But then it happened again. And again. Turns out, these killer whales were giving each other full-body spa treatments with kelp.
“I zoom in, and sure enough, there’s clear as day this piece of kelp that they’re using to rub on each other,” said Weiss.
Over just two weeks in 2024, Weiss and his team documented 30 examples of this peculiar behaviour, which they’ve now dubbed allokelping. Basically, orcas are ripping strands of bull kelp from the seafloor and using them to exfoliate each other like underwater loofahs. Science, meet whale wellness.
And this isn’t just a quirky flex. In a study published in Current Biology, researchers suggest allokelping could serve dual purposes: removing dead skin and forming tighter social bonds. Think: skincare meets quality time.
“This is a quite different way of using an object,” said Weiss, noting that tool use in the animal kingdom is usually about getting food or attracting mates. Here, the whales might just be keeping clean and keeping close.
The rubbing pairs were often relatives or similar in age, pointing to social bonding. “These guys are incredibly socially bonded,” added orca scientist Deborah Giles. She wasn’t shocked by the behaviour — orcas are famously brainy and tactile. With bigger brains (in some areas) than humans, each pod even rocks its own dialect.
Cetacean skin is delicate, according to marine mammal expert Janet Mann, and while solo rubbing isn’t new, two whales exfoliating each other? That’s fresh. “What (the study) shows is that we know very little about cetacean behaviour in the wild,” she said.
Thanks to drones, scientists are finally getting a front-row seat to this kind of underwater intimacy. Until now, whale-watching meant squinting from boats. But with drone footage? “A whole new world,” as Mann puts it.
And it’s not just about kelp. Bottlenose dolphins use sponges to hunt, others whip up mud-ring fish traps, and humpbacks blow bubble nets. But allokelping is in a league of its own — not for food, but for feels.
“This kind of feels like a moment in time for cetaceans,” said Philippa Brakes of Whale and Dolphin Conservation. “It does prove that you don’t necessarily need a thumb to be able to manipulate a tool.”
Brakes sees it as a cultural milestone. Orcas already have their own lingo and hunting customs, now they’ve added skincare to the list.
“Culture provides a phenomenal way for animals to be able to adapt,” she said. “It’s more reason to ensure that we protect their habitat as well as their behavior.”
That’s especially critical now: Southern resident orcas are critically endangered, with just 74 individuals left. And bull kelp — their exfoliating material of choice — is vanishing thanks to seabed disruptions and climate-driven heat waves. Fewer kelp forests also means fewer juvenile chinook salmon, their go-to snack.
“This study makes me wonder if one of the reasons the Southern Residents continue to visit the Salish Sea periodically even during times of low salmon abundance is to engage in allokelping,” said Monika Wieland Shields of the Orca Behavior Institute.
To top it all off, this might just be the first documented case of a whale using a tool not to eat, but to chill — and chill together.
“The objective may just be social bonding, and that would still make it a tool,” said Brakes.
So, are these whales rubbing each other down just for the vibes? Possibly. But hey, self-care is universal.
[Source: CNN Science]
