The mystery orcas are back in the Puget Sound.
For the last few weeks, a pod of unfamiliar orcas has been coming and going from the waters around Seattle and British Columbia, delighting whale watchers and making headlines as they swim through the waters home to the famous Southern Resident orca population.
Orca researchers, who painstakingly catalog every killer whale they see in the area, were intrigued: Who were these orcas and where did they come from?
They had some clues.
For one thing, they were clearly not Southern or Northern Resident orcas, who stick to their close social circles and like their home waters where they feast exclusively on salmon. That meant they were likely Transient orcas, which travel widely eating marine mammals.
The mystery orcas also sported bite marks from the cookie-cutter shark, a small deep-sea shark that leaves distinctive circular scars on whales, dolphins and large fish, research organization the Orca Conservancy said. That suggested that these orcas range farther offshore than local populations.
After documenting the new orcas, researchers officially catalogued them as T419, T420 and T421. Orca experts hypothesized that the animals were part of the Alaskan Transient population, and new artificial intelligence tools have strengthened that belief.
Shari Tarantino, executive director of the Orca Conservancy, said once the newly catalogued animals were entered into FinWave, an online database that uses AI to help people identify orcas using photo submissions, researchers made a surprising discovery: These orcas had actually been spotted before.
“Now that these three have been added into the database, the AI has detected these individuals in previous submissions,” Tarantino wrote in an email. “The ones that I am aware of were documented in Prince William Sound, strengthening the belief that these individuals may be from the Gulf of Alaska Transient stock.”
Seeing the new orcas in the Puget Sound has been an opportunity to broaden our understanding of the Transient populations, Tarantino said. Researchers have already noticed that the presumed Alaskan Transients have been socializing with animals from the local West Coast Transient population.
“We weren’t sure what to expect with the two separate populations, but as it turns out, Transient killer whales in this region seem to be more socially fluid than our Resident ecotypes that do not intermingle,” she said.
Decades of research has shown that differences between Resident and Transient orcas are stark enough to separate them as different species.
While the struggles of the Southern Resident orcas have been widely documented, these other populations haven’t had the same problems. Studies have shown that with a broader diet and a range of travel, the local Transient orcas have been thriving.
That could mean that even as resident orca numbers dwindle, traveling orcas will continue to make an appearance in local Pacific Northwest waters.
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