For many animal species, mutual body care ensures social cohesion. Researchers have now observed an extraordinary case at Orcas: the sword whales bite long hoses from seaweed and rub them between themselves and a partner to clean their skin. For the first time, it was demonstrated for marine mammals that they manufacture and use tools. So far, the behavior has only been documented in the population of southern swords in the Salish Sea between the US state of Washington and the Canadian Vancouver. It is still unclear whether other sword whales care in a similar way or whether it is a cultural uniqueness.
When it comes to maintaining your own skin, whales are inventive: some types regularly rub themselves on flat stones and thus probably remove dead skin scales. Others operate the so -called Kelping: they swim through the accumulation of seaweed (English: Kelp) and may take advantage of the fact that some of the marine plants contain substances that keep parasites away. So far, however, this whale-wellness program has been more an individual matter in which each animal takes care of its own body care.
Wellness tools
Now a team led by Michael Weiss from the Center for Whale Research (CWR) in Friday Harbor in the US state of Washington has documented for the first time that Orcas also maintain each other with the help of seaweed-a behavior that the researchers describe as “allokelping”, that is, mutual Kelping. “The seatang stems are firm, but flexible, like a filled garden hose, with a smooth outdoor area,” explains Weiss. “I suspect these properties make them an ideal tool for skin care.”
The “Bull Kelp” sea tinge used – a kind of brown algae – is typically many meters long. In order to obtain suitable pieces for skin care, the whales initially bite the algae stem and then bring it to a suitable length by further biting. Once the tool has been finished, you swim to a partner and start rubbing the stem prepared for this between yourself and the other animal. If you lose the stem, grab it again with your mouth and start again. “The discovery proves that the whales not only use tools, but also manufacture, which has never been proven with marine mugs before,” says Weiss.
Widespread in southern swords
The researchers observed the alloking ping in the southern sword whales, which is threatened with extinction, which lives in the Salisches See in the northeastern Pacific. “This whale population is the best examined orcapopulation of the world – and yet important new discoveries can still be made,” says Weiss’ colleague Rachel John. Earlier video recordings of the whales had too low resolution in order to recognize the production and use of the seaweed.
However, recordings with modern research drones revealed that the allocle ping in the southern orcas is widespread and that individuals of both genders and different age groups are alike. “Everything indicates that this is an important part of their social life,” says Weiss. According to the observations, whales were most common with close related maternal side and with animals of similar ages for allokelping.
Threatened cultural tradition
So far, it is unclear whether other whale species show similar behavior. Maybe it could be a cultural uniqueness of the southern sword whales. In the last count of the CWR in July 2024, the population only included 73 animals. Since they do not reproduce with other orcapopulations, the southern sword whales are acutely threatened with extinction. “In biological diversity, we often think of protecting the phenotypical differences in animal populations such as size, shape and color,” says Weiss. “However, the preservation of cultural and behavior -related differences can be just as important.”
Due to the increasing sea temperatures, the seaweed forests from which the orcas win their tools are declining. “Protecting the future of these seaweed forests could be important to preserve this unique culture of the southern sword whales and ensure that the population will continue to survive in the future,” says Weiss’ colleague Darren Croft.
Source: Michael Weiss (Center for Whale Research (CWR), Friday Harbor, Washington, USA) et al., Current Biology, DOI: 10.1016/J.CUB.2025.04.021
