The investigators were surprised by the generalization of this behavior, observed by a team of researchers in an Orcas community live in the Salish Sea in the United States.
The use of marine animal tools has been poorly documented, but now it has been observed that a type of orca uses algae to massage, possibly to reinforce social ties and promote skin health.
This behavior was observed by a team of researchers who used images of drones from a community of whales living in the Salish sea (northwest of the United States) and who published their results in .
As orcas They tear the end of an algae stalk, place it with each other and their partners and roll it between their bodies for long periods of time.
“We were amazed when we observed this behavior for the first time”said the investigator do (CWR), headquartered in the USA, who conducted the study in collaboration with the University of Exeter in the United Kingdom.
Until nowIt was known that several species of whales moved the algae with their heads, fins and body, probably to play or remove parasites and keep the skin healthy, but the behavior observed now with orcas is different.
Designated by the investigators as ‘Allokelping’, whales select and drop the algae, as a deliberately manufactured tool for future useand then used by individuals who work together.
Researchers were surprised by the generalization of this behavior, as males and females in all phases of life use algae in this way and are more likely to form pairs with maternal relatives near similar age.
“It seems that this is an important part of your social life”disse Weiss.
For eight of the 12 days included in the study, whales were observed to do ‘allokelping’, and researchers believe this behavior can be universal in this population.
As for the possible causes behind this behavior, researcher Darren Croft of the University of Exeter noted that Orcas often come into contact with other members of their group, touching their bodies and fins, “but the use of algae like these could improve this experience.”
Whales and dolphins have various strategies to get rid of the dead skin, and this can be another adaptation for this purpose, since Brown algae have antibacterial and anti-inflammatory properties that can be beneficial to whales.
It is well known that other orcas rub the body on smooth stone beaches, possibly to remove dead skin and parasites, but the orcas of this group were not seen to do this.
A Threatened population of Salish Sea Whales has been studied for 50 years, with only 73 whales counted on the last census from CWR in July 2024.
Although there are other orcas around the world, This group of the Salish Sea represents a genetic, ecological and culturally distinct populationsaid Weiss.
A practice of ‘allokelping’ is another proof of the uniqueness of this orca groupIf, with its disappearance, it would not only be lost 73 animals or a genetic lineage, but also “a complex society and a deep and unique set of cultural traditions,” said Croft.
The results of this study, according to Croft, highlight an additional potential threat to the future survival of these orcas, since ‘Kelp’ forests where they select their hygiene utensils are declining due to increased ocean temperature associated with global warming.
