Orcas in the Pacific are using kelp as grooming tools, and they're teaching each other how to do it. This shouldn't be surprising. But it is, because scientists thought cetacean tool use was supposed to be purely practical—a means to catch food or survive. Apparently, orcas didn't get the memo.
For decades, tool use was treated as a rare marker of intelligence, mostly observed in primates and a handful of birds. When researchers began documenting dolphins using shells to catch fish, that was already strange enough. But at least those tools served an obvious survival function. The assumption held: animals use tools to solve hunting or feeding problems. Culture—the social transmission of behaviors that don't directly aid survival—was thought to be almost uniquely human, or at least uniquely ape. We were wrong about that boundary, and orcas just pushed it further.
According to recent observations in the Pacific Northwest, orca populations have begun using kelp as grooming implements, rubbing themselves against the plants to clean their skin. More significantly, this behavior is being passed down socially between individuals, spread through the population as learned behavior rather than instinct. This represents what researchers are calling the first documented tool use among cetaceans for purposes entirely divorced from hunting or feeding. A 2025 CNN report on the behavior notes that the kelp-grooming technique appears to be cultural transmission in real time—younger orcas learning from older ones, the behavior gradually becoming more common within the group.
This matters because it suggests orca societies aren't just efficient hunting machines with social bonds. They have something closer to what we'd recognize as culture: behaviors that spread through communities, that have no immediate survival advantage, that are valued and taught precisely because they're valued. The kelp grooming doesn't make orcas better hunters or less likely to starve. It's ornamental, almost aesthetic. An orca using kelp is essentially choosing to engage in a behavior because other orcas do it, because it feels good, because her family does it.
Why this is happening now isn't entirely clear, but the mechanism is straightforward: orcas are intelligent, social creatures with long lifespans and stable family groups. They live in close-knit pods where knowledge transfer is constant. Once one individual discovers that rubbing against kelp feels nice—maybe by accident, maybe through exploration—others observe, mimic, and refine the behavior. Each generation learns from the previous one. Over time, it becomes normalized, expected, part of the group's identity. In other words, it becomes culture.
The implication is uncomfortable for those who've long used tool use as a shorthand for advanced cognition or cultural sophistication. We don't have a monopoly on either. More broadly, it suggests we've been looking for culture in the wrong places—we assumed it had to be about survival advantage, had to be economically rational. But culture isn't always practical. Sometimes animals do things because they're meaningful, because communities do them, because they're worth doing. Orcas with kelp are reminding us that meaning-making itself might be more widespread than we ever gave animals credit for.