Researchers at the University of British Columbia say they have identified a new population of pelagic killer whales that hunt the largest predators on Earth.
In a study published Friday, researchers said a pod of 49 orcas was observed hunting sperm whales off the coast of California and Oregon.
Lead author Josh McInnes said in a news release that in one case, an orca hunted a pod of nine adult sperm whales and “eventually escaped with one.”
McInnes said this is the first time an orca has been reported to have attacked a sperm whale on the West Coast.
“Other encounters have included attacks on pygmy sperm whales, predation on northern elephant seals and red pilot whales, and what appears to be a postprandial lull after scavenging for a leatherback turtle,” said the UBC master’s student. Mr McInnes said. Marine Fisheries Research Institute.
Researchers said the killer whales observed in nine encounters between 1997 and 2021 may belong to a transient killer whale subpopulation or an ocean-specific population.
There were also bite scars on the body of the cookiecutter shark, a type of parasitic shark that lives in the deep sea, allowing researchers to identify killer whales as possibly a new group, the report said.
McInnes said nearly all of the killer whales had wounds, but no other killer whales had any injuries.
“But the big question is, what position do these killer whales fit into? We don’t know…but what we do know is that they’re more likely to live in the open ocean. It’s representative of the population that you would expect to spend time with,” McInnes said in an interview.
Co-author Andrew Treitz of the UBC Marine and Fisheries Research Institute said that given the time required to collect photos and recognize that the animals are distinct from known populations, new orca populations are unlikely to emerge. He said the discovery was “very unique”.
The researchers said they also observed physical differences in orcas, such as spots on their fins and saddles.
They said they want to record more sightings and data from the new population to investigate exactly how these killer whales differ from other recorded populations.
Mr McInnes said this discovery was the first part of a fun puzzle they were working on.
“We’re just at the tip of the iceberg of what these whales are doing. I mean, are they all the same population? Are there more than one? We don’t know. So this is us “We feel like it’s kind of a big start to the next step in our research, where we’ll probably get more sightings and more information,” McInnes said.
This report by The Canadian Press was first published March 15, 2024.
