Holly Fearnbach and John Durban’s morning started with a ping via text around 5:30 a.m. A couple who lives on the west side of San Juan Island had picked up some chatter on their underwater hydrophone from local killer whales.
By the 7 a.m. September sunrise, the whale researchers were motoring across the glassy water offshore of the island. They were watching for black dorsal fins that slice through the water, rising and falling, sometimes alone, sometimes in clusters of family members.
Once they spotted the orcas and came within range, the scientists launched a small drone — an unmanned hexacopter — to fly 100 feet or more above the killer whales. The drone is outfitted with a camera for shooting aerial photos. They were particularly interested in an endangered population known as the southern resident killer whales.
The full-body images provide critical information about the weight and shape or “body condition” of each of the local orcas. It’s a non-invasive physical exam in a snapshot that can reveal whether a whale is malnourished or a healthy weight. It can also detect pregnancies.
“There are other ways to tell if a population is going up or down, but we want to know how they’re doing before they die,” said Durban, a population ecologist with the National Oceanic and Atmospheric Administration (NOAA) Fisheries’ Southwest Fisheries Science Center.
“If there’s a problem you want to be able to say, ‘These whales are skinny, let’s do something about it,’ rather than once you’ve lost a bunch of animals,” he said. “That’s the real goal.”
And in recent decades, the southern residents have, in fact, lost a bunch of animals. The population of orcas that call Washington and British Columbia home dropped from 98 orcas in 1995 to 77 today. More than a decade ago, the government declared that the southern residents were at serious risk of extinction and they’re protected under the U.S. Endangered Species Act.
Experts know that a shortage of chinook salmon — the southern residents’ preferred food — is a key cause of their decline. But these photos are providing concrete links between orcas that appear emaciated and die shortly after, links that could help drive regulations on fishing and boat traffic to safeguard the killer whales and could highlight which salmon runs are most important to the orcas’ survival.
“We know animals have to eat, but we still need evidence that this is an issue because management actions are complicated and controversial,” Durban said. “We’ve got to make sure the evidence is bulletproof.”
This is the fifth season that Durban and Fearnbach have collected overhead photos. They first snapped images from the windows of helicopters for two years beginning in 2008, then developed and began using their groundbreaking drone technology in 2015. The approach is relatively inexpensive and efficient while allowing the collection of large amounts of crucial data.
“This tool is extremely valuable for studying marine mammals,” said Michael Moore, senior scientist at Woods Hole Oceanographic Institution in Massachusetts, by email.
The use of drones with whales, he said, allows “high resolution, safe perspective on their overall health, that is relatively affordable and thus has the potential to generate long term — decades long — data sets on the status and trends of endangered populations and species.”
‘You can see how thin she is’
Durban and Fearnbach, director of marine mammal research for the Puget Sound-based nonprofit SR3, just completed their 2017 survey of southern resident orcas. The project is a collaboration between SR3, NOAA’s Southwest Fisheries Science Center and the Vancouver Aquarium’s Coastal Ocean Research Institute, the latter represented by Lance Barrett-Lennard, a research scientist. All three have spent decades studying whales around the world.
But for many, the region’s orcas hold a special fascination. Orcinus orca are a large, charismatic dolphin, known for playful behavior like bobbing out of the water in “spyhops.” The local population lives in groups called pods, which are lettered J, K and L. The pods are close-knit, female-led family units. Scientists with the Center for Whale Research have tracked and photographed the area’s orcas for decades, assembling detailed family trees.
The local orcas “have always got each other’s backs. We don’t see jousting or altercations for status or breeding rights,” said Howard Garrett, co-founder of the nonprofit Orca Network. “There is so much about them that is unheard of in wildlife biology elsewhere. It’s fascinating.”
Researchers internationally have assembled evidence demonstrating that different orca populations have distinct cultures. They have their own unique, recognizable languages used to call to each other and more closely related groups have accents of the same language. Different populations have specialized diets: southern residents and northern residents, which reside from Vancouver Island up to southeast Alaska, hunt fatty chinook salmon. Orcas known as “transients” that travel more broadly and live in very small family groups eat seals and other marine mammals. A third Northwest population, the “offshore” orcas, dines on sharks.
On a recent September morning, the researchers captured images of two southern resident orcas traveling together. Based on the pattern of whitish “saddle patches” near their dorsal fin and the shape of the fin, the scientists identified them as L41, a 40-year-old male, and L25, a female believed to be nearly 90 years old. The two are the oldest male and female orcas of the southern residents.
The day was sunny and cool and Fearnbach padded barefoot along the deck of the Vancouver Aquarium research boat. Perched under a towel to cut the sun’s glare, she watched a video feed from the drone, directing Durban, who was driving the copter, to guide it right or left to line up images.
The scientists have special government-issued research permits to both get closer to the whales than is allowed by other vessels and to fly the drones over the protected marine mammals. The team doesn’t approach closer than 100 yards from the orcas, and is often much farther away.
The $30,000 custom-built, light-weight drone can fly for about 15 minutes before it needs a battery swap. The device is small and quiet, and the orcas are unaware of its presence.
In addition to the camera, the drone carries a height-measuring laser altimeter. Knowing the altitude, the scientists can determine the exact dimensions of the orcas down to a few centimeters, an analysis called “photogrammetric health assessment.”
Some of the images being gathered are alarming.
Fearnbach opened a pair of photos on her laptop. They show a female orca called J28.
“This was taken just a year apart, when she is heavily pregnant,” Fearnbach explained, pointing first to an image of a plump orca. She turned to the second photo of J28 and her baby. “And this is right before she died. You can see how thin she is.”
“It’s really hard to tell conditions from a boat,” Durban added. Orcas are well reinforced with bones and muscles along their backs to support their large dorsal fins, so their shape fluctuates less looking at them from a sideview. The overhead images tell a different story.
“Science doesn’t need to be complicated,” he said. “Anyone can look at these images and say, ‘That’s a fat or thin whale.’”
Saving salmon to save orcas
This year multiple runs of the local chinook — some of which are also protected by the Endangered Species Act — had their worst returns in decades. And at least one of the orcas that the researchers recently photographed was clearly in poor physical condition; he later disappeared and is presumed dead.
In dire cases such as this, malnourished orcas have a “peanut head” where instead of appearing like a rounded bullet, the contour of their head shows a depression where fat stores behind their blowhole are depleted. The scientists are still analyzing thousands of images to detect more subtle health changes in other whales in this population.
Before this month’s survey of southern residents, the scientists were in Canada photographing northern residents, a population that is growing and the whales appear to be in better health. While tracking resident orcas, the researchers also take pictures of transient whales, who are practically roly-poly thanks to a strong seal population, and humpback whales.
A research group led by Sam Wasser at the University of Washington is doing its own non-invasive orca research, collecting killer whale fecal waste and testing it for stress and pregnancy hormones and other health indicators. If the fecal research shows that an orca is pregnant, that can be verified and further monitored using the aerial photos. The Center for Whale Research also carefully tracks the southern residents and has a wealth of historic data. There’s a project currently underway to combine all of these sources of information into one database.
“We’re going to have medical profiles for these individual whales,” said Lynne Barre, recovery coordinator for the southern resident killer whales at the West Coast office of NOAA Fisheries. “That is going to help strengthen our ability to pinpoint what the problems are and identify what we can do about it.”
The hope is that with data gathered year after year and during different seasons, the researchers can see when and where the orcas are showing signs of malnutrition and respond accordingly. But more work is needed to figure out which body condition measurements best indicate an orca’s health and what qualifies as a tipping point necessitating an immediate response.
Chinook recovery currently is coast-wide to help the orcas, but some runs are more important to them than others. Salmon habitat restoration, runs boosted with hatchery fish, a change in when people can catch salmon, or other strategies could increase their numbers in key times and places. The question is: “Can we be a little more precise on what will give us the most benefit for the whales?” asked Barre.
And the scientists are concerned not only about the amount of chinook salmon available, but also access to the fish. If favorite feeding areas are overrun by fishing boats, whale watchers and other vessels, that could exacerbate problems.
“Whales are kind of like us,” Durban said. “We can’t go anywhere in the ocean and put a rod in the water. We’ve learned where to do it, and they have as well. So it’s really important that they’re not disturbed in those areas where they’ve learned to feed.”
Despite the population declines, the scientists remain hopeful that the southern residents can rebound by adapting recovery plans to their needs. Because southern resident orcas don’t mate with other killer whales, researchers are concerned about the number of reproductive males and females and the survival of calves.
But the population’s overall numbers have previously dropped even lower than they are today, dipping to 66 in 1973, due mostly to whales being captured for public display. And the orcas were able to come back, growing to 98 killer whales before slipping again.
“It’s not a lost cause,” Durban said. “We can adaptively help them recover. It’s still very plausible.”