Tuesday, October 20, 2020
Oct. 20, 2020

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Researchers attach cameras to Pacific Northwest orcas, revealing a marvelous underwater world

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For nearly a month the team has been at sea, marveling at the prowess of southern and northern resident killer whales as they follow the orcas’ foraging rounds, using a drone and stick-on cameras to record the daily lives of orcas, even underwater.

The surprises keep coming: How far the orcas, especially the southern residents, travel in their hunt for salmon. How affectionate the orca families are with one another, constantly touching. And their incredible athleticism, as orcas hunt down and kill their prey.

“They are really efficient fish slayers,” said Andrew Trites, head of the Marine Mammal Research Unit at the University of British Columbia. He is leading this team on a monthlong research trip with eight others packed aboard the Gikumi, a 1954 wooden work boat.

By day 27, the team has tracked the whales from the northernmost end of Vancouver Island to its southern tip; along the Strait of Juan de Fuca, and out to the open ocean and back in their quest to get to this truth: Are the orcas getting enough to eat while in their core summer foraging ground?

No one disputes that chinook salmon, the orcas’ primary summer food, have declined overall. The more precise question is whether the orcas have enough salmon to stay fed while in the Salish Sea, the transboundary waters connecting the U.S. and Canada, at this time of year.

To find out, researchers have followed the whales, filming them with a drone, and sticking tags the size of a paperback book to the orcas with suction cups, transforming the orcas into videographers, recording their travels and hunts underwater.

The tags are loaded with detectors that record the sounds of the orcas: their breathes, clicks, buzzes and calls. They can track the direction and speed of their movement in the dark to see how they dive, roll and sprint. They even film their social interactions as they swim, play and hunt, share food and touch.

Southern residents struggle

The northern and southern resident orcas are the same animal. But they differ in their primary foraging range. And that, it seems, has made a crucial difference. The northern residents live in cleaner, quieter water with access to a greater variety of fish. They are far more abundant than the southern residents, with 310 northern residents counted in 2019. The northerns also have been steadily increasing for decades, while the southern residents are battling extinction.

There are only 73 southern residents left, counting the newest baby, born to Tahlequah, or J35, on Sept. 4. That birth in particular was a ray of hope for a mother whale who raised worldwide concern when her last calf died after living only one half-hour in the summer of 2018. She refused to let the calf go, traveling for 17 days and more than 1,000 miles with the dead calf.

The new calf is healthy so far, and is the third born to the southern residents since 2019. The scientific consensus, however, is that the southern residents remain at acute risk of extinction due to at least three main threats: pollution, vessel noise and disturbance, and lack of readily available quality food.

That last bit is what Trites and the team want to test. They seek to learn if there are differences in the feeding efficiency of the two populations.

“We may find what people suspect, or we may find there is no difference (between the two populations), or that the southern residents have an easier time, which would be a real surprise,” Trites said. “But the point is to find out, by gathering data and not just assume that food, and in particular food at this time of year in this region, is the problem.”

The stakes are high, with extinction stalking the southern residents. “It would be tragic if we let them go extinct because we were blinded by our convictions, and were not looking for the problem in the right spot,” he said.

New research method: “Orca-cam”

Even these experienced killer whale observers have been astounded at the underwater world that has unfolded as the whales carry a camera on their skin for hours or even days. The tag is designed to pop off and float to the surface, where scientists retrieve it.

The team is posting their daily activity on Facebook, and has already shared remarkable videos and photos for the public to enjoy. They’ve dubbed the tag the “orca-cam.”

It’s tricky work. Finding the orcas is the first problem. Getting a tag on a wild orca is the next one. It takes strength and dexterity to extend a 25-foot-long carbon-fiber pole from a bouncing skiff to tap the 2-pound tag onto a swimming killer whale, aiming for the area right below the dorsal fin. So far the team has been able to tag two southern residents, L87 and L88, and nine northern residents.

Recording the whales on the high seas with a flying camera isn’t easy either — especially when it is time to catch the whizzing drone from the deck of a bouncing boat.

The tags allow researchers to come along for the kill, as orcas prowl the deep. “It is really quite exciting, they are in the deep, dark water, it sounds like a submarine, ping, ping, ping,” Trites said, describing the orcas’ echolocation clicks. “Faster and faster, it turns into a buzz and you know the kill moment is coming.” Then comes a satisfying crunch.

“It is quite thrilling, you feel like you are part of the hunt.”

The orcas are unrelenting predators.

“They are extremely efficient, they are eating on the run,” Trites said. “They don’t miss a beat. They catch a fish, rip it up, someone else gets a chunk, and they are moving all the time.”

Watching the orcas in action has dispelled any notion for the researchers that these are fragile animals.

“You see how tough these animals are, they are built to survive,” Trites said. “They are covered in battle scars, I feel like I am seeing them in a way I have never understood. They have been traveling together for decade after decade, it reframes a new impression of their lives, instead of just seeing them from the surface, from a boat.”

What story will the data tell?

Scientists only have first impressions now from what they have seen while at sea. It will take analysis of the data they have gathered to begin to put the story together.

Another piece of the research involves tracking salmon along with the whales. The vessel is outfitted with sophisticated fish finders that depict the bottom to a depth of more than 1,600 feet, and show where the fish are, and even the species.

One surprise may turn out to be that even in summer the orcas are taking bottom-feeding halibut in their hunts. That would explain why the team saw an orca with its dorsal laid down on the sea floor where halibut are regularly caught by fishermen. Was it flushing and chasing the fish?

Also in the mix is tagging data gathered this summer by another team, which is catching chinook at Port Renfrew and releasing the salmon to determine where they go.

The Gikumi team has a new respect for the orcas built from basically trying to be a killer whale, following the pods and salmon constantly on the move. Southern residents in particular travel huge distances, researchers learned. Swimming more than 150 miles over the span of two days is nothing for them.

“They don’t park in one spot. They are constantly intercepting fish in different locations; it’s appears to be a much better strategy to run a trap line than to wait for the fish to come,” Trites said.

Yet even while on the move, the orcas are constantly touching: bumping into one another, sliding alongside one another, and the little ones snugging up to their mother’s flipper for a belly rub. It’s how they stay in touch in a vast ocean, and constantly renew their bonds.

The team got their first glimpses of the whales’ continual touching and play with drone footage last year; it took their breath away.

Imperiled pods in hostile waters

The team’s work coincided with massive fires all over the West Coast, and the smoke sometimes was so thick on the water, the researchers could only track the orcas by listening for their breath. They never did see Tahlequah and her calf.

They were saddened by the pall of smoke, and wondered how it affected the whales. They were also concerned by the amount of boat traffic in busy shipping lanes in the southern residents’ core habitat on the west side of San Juan Island, in addition to private recreation boats.

One day they counted at least 100 fishing boats off San Juan Island, more than one for every southern resident orca. They also, early in their cruise, were shocked to see a northern resident with a flasher used to catch salmon dangling from the gear embedded in its mouth.

As their vessel followed the whales off the coast of the city of Vancouver, B.C., the team also grappled with the realization of all that the southern residents deal with.

“What struck us was how much the world has changed for them, we almost felt suffocated, quite oppressed, when we came into the city again,” Trites said. “We felt shocked to know the southern residents come so close to Vancouver. People think this is a problem somewhere else. No. This is right off the beach, that is part of their range and an important feeding area for them. People have not appreciated that before.”

Trites hopes that what the team has seen and heard this summer will help not only answer scientific questions, but also show the public a little more of the remarkable lives of Orcinus orca, the top predator in every ocean of the world.

“They are supreme athletes, they have this incredible ability to survive, track down fish, surface, breach, leap, spy hop, stay in touch with each other constantly,” Trites said. “It is really remarkable to have this chance to follow them, although we do a lousy job of keeping up, I must say.”

He was struck by the similarities of orca and human society, in the strong family bonds he witnessed, at how no orca would ever let another in the family go without food. And struck, also, when observing the southern residents, that this is an animal far too tough to count out.

“They are battle hardened, and battle ready. And they have a will to survive. They are not going down without a fight,” he said.

“It is up to us to do our part to ensure we don’t get in the way.”

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