Killer whales spotted grooming each other with seaweed
Killer whales have been caught on video breaking off pieces of seaweed to rub and groom each other, scientists announced Monday, in what they said is the first evidence of marine mammals making their own tools.
Humans are far from being the only member of the animal kingdom that has mastered using tools. Chimpanzees fashion sticks to fish for termites, crows create hooked twigs to catch grubs and elephants swat flies with branches.
Tool-use in the world's difficult-to-study oceans is rarer, however sea otters are known to smash open shellfish with rocks, while octopuses can make mobile homes out of coconut shells.
A study published in the journal Current Biology describes a new example of tool use by a critically endangered population of orcas.
Scientists have been monitoring the southern resident killer whales in the Salish Sea, between Canada's British Columbia and the US state of Washington, for more than 50 years.
Rachel John, a Masters student at Exeter University in the UK, told a press conference that she first noticed "something kind of weird" going on while watching drone camera footage last year.
The researchers went back over old footage and were surprised to find this behaviour is quite common, documenting 30 examples over eight days.
One whale would use its teeth to break off a piece of bull kelp, which is strong but flexible like a garden hose.
It would then put the kelp between its body and the body of another whale, and they would rub it between them for several minutes.
The pair forms an "S" shape to keep the seaweed positioned between their bodies as they roll around.
- For fun and clean skin -
Whales are already known to frolic through seaweed in a practice called "kelping".
They are thought to do this partly for fun, partly to use the seaweed to scrub their bodies to remove dead skin.
The international team of researchers called the new behaviour "allokelping," which means kelping with another whale.
They found that killer whales with more dead skin were more likely to engage in the activity, cautioning that it was a small sample size.
Whales also tended to pair up with family members or others of a similar age, suggesting the activity has a social element.
The scientists said it was the first known example of a marine mammal manufacturing a tool.
Janet Mann, a biologist at Georgetown University not involved in the study, praised the research but said it "went a bit too far" in some of its claims.
Bottlenose dolphins that use marine sponges to trawl for prey could also be considered to be manufacturing tools, she told AFP.
And it could be argued that other whales known to use nets of bubbles or plumes of mud to hunt represent tool-use benefitting multiple individuals, another first claimed in the paper, Mann said.
- Culture could soon be lost -
Michael Weiss, research director at the Center for Whale Research and the study's lead author, said it appeared to be just the latest example of socially learned behaviour among animals that could be considered "culture".
But the number of southern resident killer whales has dwindled to just 73, meaning we could soon lose this unique cultural tradition, he warned.
"If they disappear, we're never getting any of that back," he said.
The whales mainly eat Chinook salmon, whose numbers have plummeted due to overfishing, climate change, habitat destruction and other forms of human interference.
The orcas and salmon are not alone -- undersea kelp forests have also been devastated as ocean temperatures rise.
Unless something changes, the outlook for southern resident killer whales is "very bleak," Weiss warned.
dl/phz
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News.com.au
2 days ago
- News.com.au
Killer whales spotted grooming each other with seaweed
Killer whales have been caught on video breaking off pieces of seaweed to rub and groom each other, scientists announced Monday, in what they said is the first evidence of marine mammals making their own tools. Humans are far from being the only member of the animal kingdom that has mastered using tools. Chimpanzees fashion sticks to fish for termites, crows create hooked twigs to catch grubs and elephants swat flies with branches. Tool-use in the world's difficult-to-study oceans is rarer, however sea otters are known to smash open shellfish with rocks, while octopuses can make mobile homes out of coconut shells. A study published in the journal Current Biology describes a new example of tool use by a critically endangered population of orcas. Scientists have been monitoring the southern resident killer whales in the Salish Sea, between Canada's British Columbia and the US state of Washington, for more than 50 years. Rachel John, a Masters student at Exeter University in the UK, told a press conference that she first noticed "something kind of weird" going on while watching drone camera footage last year. The researchers went back over old footage and were surprised to find this behaviour is quite common, documenting 30 examples over eight days. One whale would use its teeth to break off a piece of bull kelp, which is strong but flexible like a garden hose. It would then put the kelp between its body and the body of another whale, and they would rub it between them for several minutes. The pair forms an "S" shape to keep the seaweed positioned between their bodies as they roll around. - For fun and clean skin - Whales are already known to frolic through seaweed in a practice called "kelping". They are thought to do this partly for fun, partly to use the seaweed to scrub their bodies to remove dead skin. The international team of researchers called the new behaviour "allokelping," which means kelping with another whale. They found that killer whales with more dead skin were more likely to engage in the activity, cautioning that it was a small sample size. Whales also tended to pair up with family members or others of a similar age, suggesting the activity has a social element. The scientists said it was the first known example of a marine mammal manufacturing a tool. Janet Mann, a biologist at Georgetown University not involved in the study, praised the research but said it "went a bit too far" in some of its claims. Bottlenose dolphins that use marine sponges to trawl for prey could also be considered to be manufacturing tools, she told AFP. And it could be argued that other whales known to use nets of bubbles or plumes of mud to hunt represent tool-use benefitting multiple individuals, another first claimed in the paper, Mann said. - Culture could soon be lost - Michael Weiss, research director at the Center for Whale Research and the study's lead author, said it appeared to be just the latest example of socially learned behaviour among animals that could be considered "culture". But the number of southern resident killer whales has dwindled to just 73, meaning we could soon lose this unique cultural tradition, he warned. "If they disappear, we're never getting any of that back," he said. The whales mainly eat Chinook salmon, whose numbers have plummeted due to overfishing, climate change, habitat destruction and other forms of human interference. The orcas and salmon are not alone -- undersea kelp forests have also been devastated as ocean temperatures rise. Unless something changes, the outlook for southern resident killer whales is "very bleak," Weiss warned. dl/phz
ABC News
3 days ago
- ABC News
Orcas swimming in bull kelp beds
Orcas will select a piece of bull kelp and trim it down to size so they can rub it between each other
ABC News
3 days ago
- ABC News
Orcas filmed making tools out of kelp to give each other massages on the move
Humans will spend big bucks on a seaweed spa treatment, and why not? It's rejuvenating and relaxing: just ask a group of orcas. Southern Resident orcas — an endangered coastal population that swims off North America's Pacific north-west — have been observed rubbing specially fashioned pieces of kelp between themselves to create what looks like a massage on the move. Dr Weiss and his colleagues filmed these interactions via drone cameras in the Salish Sea, which is located in the Canadian province of British Colombia and the US state of Washington. Their observations were reported today in Current Biology. The orcas were filmed biting down on the kelp, jerking their heads and swimming downwards to separate a segment of the seaweed that sits between its base and leaf-like blades. "It's like a garden hose full of water: it's flexible, but it is also tough," Dr Weiss said. Other cetaceans, such as humpback whales and right whales, have been observed rubbing themselves in kelp and even wearing the seaweed like a hat. This behaviour is called 'kelping', but it is very different to what the orcas were observed doing, explained Olaf Meynecke, who leads the whales and climate program at Griffith University. Because the orcas are using the kelp collaboratively to massage each other, the behaviour has been named "allokelping" — allo being a term used in biology to signal "different" or "other". Dr Meynecke, who was not involved in the study, described the way this group of orcas engaged with the kelp as "much more active" than what has been observed with other cetaceans. "The orcas are grabbing it, they're moving it, they're actually putting it against another individual," he said. "The humpback whales and [other] baleen whales haven't done that; they are just happily rolling in it." Dr Weiss and his team recorded allokelping 30 times over eight (out of 12) days of filming in 2024. While the orcas themselves cannot explain the allure of kelp roller massages, Dr Weiss said there were hints in the data that could explain why they might do it. They found that individual orcas were more likely to allokelp with close relations along their maternal line and with individuals of similar ages, suggesting the behaviour served a social function. "They live in these very complex potentially challenging social environments where they're having to track dozens of relationships," he said. But the social benefits of this grooming behaviour may also have a element of skin care. When orcas shed their skin, it looks greyish and "peely", Dr Weiss said, and there is some evidence that individuals are more likely to engage in allokelping when they look peely. "We can't say for sure that it's actually removing the dead skin … it could be treating something about the discomfort related to dead skin," he said. Dr Meynecke from Griffith University has previously hypothesised that humpback whales may gain pharmaceutical benefits from kelping, and the orca's increased enthusiasm for allokelping when they shed skin might support his idea. Using an object to achieve a goal takes a bit of brain power, and it's a feat even more impressive when a species takes the extra step of making their tools, as these orcas have. But they're not alone: California crows cut pandanus leaves to skewer grubs in tree holes, chimpanzees sharpen sticks to 'fish' for termites, and elephants have been filmed using hoses. In 2008, bottle-nosed dolphins in Shark Bay, Western Australia were reported using sponges as tools to protect their noses while foraging on the sea floor. Georgetown University researcher Janet Mann, who first recorded this behaviour, said the latest study was "exciting", but pointed to her observations of "sponging" to challenge the claim that this is the first time whales or dolphins have been observed making tools. "It's a very delicate operation to detach a basket sponge from the sea floor without destroying the integrity of that basket," she said. But, she agreed, the use of tool to mutually groom each other was "unusual". "Chimpanzees will use leaves and sticks to groom themselves … but to mutually groom each other [with a tool] is unusual," she said. Southern Resident orcas are culturally and genetically distinct from other orcas in their region and communicate in a separate dialect. In the 1980s, they made headlines when they went through a fad of wearing dead salmon as hats — a trend that is rumoured to have returned. Dr Weiss said it wasn't clear whether this socially learned behaviour is a new fad, or ancient part of orca culture. Philippa Brakes, a cetacean ecology researcher at Massey University who was not involved in the study, said that the behaviours of this population made them unique. To do this, Dr Brakes said reducing ocean noise was important, as cetaceans communicate and learn from each other using added that the bull kelp orcas use was under threat from warming waters, and emphasised that the kelp needed to be protected in order to protect the whales' culture.
