A discovery of unique killer whale behavior may be the first documented time a marine species has been seen using and creating tools for something not food-related. The finding was made in Washington by the Center for Whale Research, and it wouldn’t have happened without the diligence of researchers.
“It was almost like puzzle pieces coming together because we started noticing with the great drone camera, but we were unsure if it was something new, a one-off or two-off situation, if it’s just something weird they’re doing, they do weird things all the time,” said Rachel John, a researcher with the Center for Whale Research.
Over several periods between April and July 2024, researchers such as John, Dr. Michael Weiss, and others watched as a whale would cut a piece of kelp loose, pin it on another Orca, then rotate its body to roll the kelp on the other whale. In some instances, the other Orca would return the favor.
“This is a major part of their social lives… we are now seeing this behavior more times than we are not,” Weiss said.
The team has dubbed the behavior “allogrooming,” and while they haven’t been able to definitively show the purpose, they theorize the whales use kelp to care for each other’s skin.
“We have found some evidence that whales with more dead skin are more likely to engage in this behavior, but we also need to see if they engage in this behavior enough, and whether they start to effectively remove dead skin,” Weiss said. “It’s also a case of tool manufacturing or tool fashioning. Both of those things are quite rare in animals generally and particularly rare in marine mammals.”
It’s the first documented case of tool use and tool creation by a marine species, according to the Center for Whale Research. CWR also says it could also potentially be the first occurrence in which a tool is created by an animal that benefits two animals at the same time, and the first use of a tool by an animal using their body, rather than an appendage.
“It’s quite remarkable the way they managed to manipulate this kelp. It requires coordination between the two whales,” Weiss said. “Their ability to coordinate their movements, to sense where the kelp is, and to have, not hand-eye coordination, but the physical ability to move their bodies the way they need to is really impressive.”
The discovery was made thanks to new drones the Center acquired after a grant from the Rose Foundation. Weiss and his team are continuing to look into the behavior as they study other aspects of killer whales as well.
So far, Weiss says it’s almost certainly a learned behavior that is distinct in the J, K, and L pods that make up the Southern Resident Orcas. The transient Biggs Killer Whales that migrate through the Puget Sound and Salish Sea do not exhibit the same behavior, despite cutting kelp free and moving through bull kelp forests.
“We also want to look over time to see if whales who do this behavior together are more likely to then show other kind of cooperative behaviors, like hunting together and sharing food and other forms of social interaction to really demonstrate more clearly whether or not this behavior helps build social bonds,” Weiss said.
The Center for Whale Research is a non-profit organization predominantly supported by public donations. For more information, you can visit their website.
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