These Local Dog Detectives Sniff Out Everything From Drugs to Diseases
We’ve long used dogs in police work for drug detection and in disasters to find people trapped in rubble. Now, their great sniffing ability is being used in a wider array of fields—from medicine to security to conservation.
Lumbering down a dike beside a leafy taro patch at Kaua‘i’s Hanalei National Wildlife Refuge, Solo, a lanky, 80-pound labrador retriever, tilts his golden head and takes a long sniff. Invisible scent particles land on the naked patch of skin at the tip of his longish snout. If I watch carefully enough, I might see the moist muscular flap cupping his right nostril inflate followed quickly by the left, indicating a scent he recognizes.
What I can’t see, no matter how carefully I look, is what is happening inside Solo’s nose. As he inhales, a fold of tissue splits the incoming air in two directions, one path for breathing and the other for a recessed area in the back of his nose dedicated to smelling. Here, air gets filtered much the same way a humpback whale uses its baleen to sift krill out of water, and a few of Solo’s 300 million olfactory receptors fire, telling him his target odor is near. Now, he just has to find its source.
Dogs have a skill we lack—they can breathe in stereo. That is, one nostril at a time. This helps them determine the location of smelly things. And in an instant, Solo is stretching the full length of his 12-foot leash, his muscular body pulling his handler, Kyoko Johnson, behind him. Johnson owns Country Canine Dog Training on O‘ahu.
When Solo drops his head, sniffing in bursts, we know he’s close. It helps that dogs can sniff and breathe out at the same time, another trick up their sleeves—or snouts. They do so by exhaling through the slits at the side of their nose while continuing to inhale. The exhalation stirs up cyclones of scent particles, concentrating the smell. Solo zigs and zags. Then, he sits down hard, looking back at Johnson, indicating he’s pinpointed his target hidden in a clump of overgrown grass: a dead duck.
Dogs are Olympic olfactorians, their noses smell-processing factories. Approximately 30 percent of a dog’s brain is dedicated to this sensory skill. A well-known 2006 study showed that trained dogs could detect 1 to 2 parts per trillion of a banana-scented solvent. Their sense of smell has been reported to be as much as 100,000 times greater than ours. In her book Being A Dog: Following the Dog into a World of Smell, Alexandra Horowitz explains that the average cinnamon roll has about a gram of cinnamon, a scent that tends to scintillate our human noses. When we walk into a house, we can instantly detect the luscious scent of freshly-baked cinnamon rolls. “Now imagine the smell of 1 trillion cinnamon rolls. That’s what the dog coming in with us smells when we enter.” No wonder they drool at the first whiff of food. Furthermore, we smell the entirety of a cinnamon roll; dogs smell each ingredient in the recipe. You could say we smell in black-and-white, and dogs smell the way we see—in technicolor.
We may know about the dogs used to find people—dead and alive—at the World Trade Center site after 9/11. In parts of Europe dogs are being used to find criminals based on the scents they leave behind. Another Labrador retriever, this one named Tobias, is sniffing out invasive Argentine ants on Santa Cruz Island off the coast of Southern California. In Australia, dogs are trained to sniff out the scat of an endangered catlike marsupial, the tiger quoll. In New Zealand, where dogs have been used for conservation work for more than 100 years, a small terrier mix named Piri inspects for rodents aboard ships headed for outer islands where the country’s threatened kiwi bird and the world’s only nocturnal flightless parrot, the kakapo, live. Water samples from Kaua‘i streams are being sent to Mainland labs where sniffer dogs walk a “scent bar” and identify samples containing human excrement. Turns out, Hawai‘i has its share of scent-detection dogs, too, besides those K9s working with police, military and TSA.
On Kaua‘i, Nicolai Barca uses his tan and white “scruffy mutt” for what we usually think of when we think of working dogs: hunting. Only, in this case, the twist is 35-pound Tako noses out invasive animals including pigs and goats so they can be removed from protected conservation areas managed by The Nature Conservancy. Barca and Tako commute to work via helicopter, and their efforts can be followed on Instagram at #takotheconservationdog.
Over on Hawai‘i Island, 4-year-old Makalani, a 25-pound English springer spaniel with long brown ears that cup his face, led biologists to discover a band-rumped storm petrel nest, hidden from sight deep in a small tunnel of hardened lava at the 7,000-feet elevation between Mauna Loa and Mauna Kea. It confirmed the first-ever historical find of the endangered seabird’s nest in the main Hawaiian Islands. “Makalani’s my favorite co-worker ever. He’s so hard-working,” says Nicole Galase, Seabird Project Leader at the Center for Environmental Management of Military Lands. Galase started working at U.S. Army Garrison-Pōhakuloa Training Center in 2015, fresh from graduate school in New Zealand where she was well aware of the country’s long history using dogs in conservation. “Makalani’s a great tool, but like Teresa, his handler, will tell you, he’s just a tool in the process. If I don’t do my part of the job, my research to figure out where I want him to go, he could search for eight hours a day and he won’t find anything.”
At wind farms on Maui and O‘ahu, dogs are employed to find endangered birds and bats that collide with the turbines. When Makalani isn’t sniffing out seabirds, he and his handler, Teresa Gajate, fly from Hawai‘i Island to Maui nearly every week to search for downed birds and bats. Johnson’s Solo got his start working wind farms on O‘ahu.
Also on O‘ahu, Paddington is a 10-year-old yellow Labrador retriever who weighs in at a svelte 60 pounds. He’s not much for romping with others of his kind at the dog park, but he’s perfectly suited for his dawn patrol gig with Orkin Pest Control, sniffing around restaurants, hotels, businesses, nursing homes and elsewhere for the stray bedbug, a tiny insect that can ruin a guest’s experience and a business’ reputation.
There’s also discussion about using dogs to detect the Rapid ‘Ōhi‘a Death fungus on Hawai‘i Island.
The possibilities for dogs are almost endless. Think of it: You can put your dog to work. It sounds fun, right?
Well, don’t quit your day job just yet.
Paddington’s handler, Herb Nakamura, is a retired Hawai‘i Police Department K9 handler and trainer. “Over the years I’ve found pet lovers do not make the best handlers,” he says. “My detection dogs are not running around the house. They’re not pets. They’re working dogs. It’s not something that anybody can do. You have to have patience. It’s time consuming.”
It takes hours and, in some cases, years of training, learning a dog’s behavioral signals, working out a way for the dog and handler to communicate with each other. It can also be expensive. There’s the training, sometimes requiring trips to the Mainland. Plus, gear. Many dogs doing fieldwork wear GPS units attached to their collars, both to pinpoint their location in case they get too far from their handlers and to determine whether they’ve completely covered their assigned territory. Makalani wears booties to protect his feet from sharp ‘ā‘ā lava. When working on a national wildlife refuge with endangered birds everywhere, protocols require Solo to wear a muzzle and work on a 12-foot leash.
Dogs are being used in all of these situations in the hope they’ll do a better job than humans—either finding things we cannot or finding them faster. But are our four-legged friends always the answer?
That’s what Michelle Reynolds, a wildlife biologist with the U.S. Geological Survey, is testing in Hanalei where the endangered koloa maoli, or Hawaiian duck, is dying at a concerning rate due to avian botulism, a paralytic disease. All five of the endangered wetland species found at Hanalei National Wildlife Refuge can contract the disease, but it’s the ducks that are most susceptible due to the way they feed, by dabbling—that is, slurping up insects in shallow water with their unique bill, which filters out water. The ingestion of as few as four or five insects carrying the neurotoxin can kill a full-grown duck. Basically, we’re talking food poisoning, and since 2011, more than 1,000 endangered koloa maoli have died from it. During this time, volunteers and staff have dedicated thousands of hours walking hundreds of acres of wetlands and taro fields on foot in search of any diseased birds. One undiscovered infected carcass can quickly lead to more if it’s not removed before flies find it, lay eggs, and other birds feed off the thousands of resulting maggots, creating a cycle of death that’s hard to break.
For three years, I’ve walked these taro fields as a volunteer looking for sick and dead ducks. Every week, I worry I’m walking by a carcass hidden in tall grass or plopped in the center of a lo‘i blocked by leafy taro. It would seem a dog could easily find a carcass just by standing in one spot and taking a good long sniff, covering more ground in less time than a human.
Turns out, it’s not that easy. The leash limits how far Solo can range and means a handler has to follow in his footsteps. It may not be as time efficient as letting Solo run free, but it does ensure Solo won’t trample a taro farmer’s crop or flush a nesting bird. Then, there’s the way scent swirls in the valley and pools in the water below the dike, requiring all lo‘i be circumnavigated. Reynolds approaches the use of dogs as a scientific study, so there are many trials to conduct and a wide variety of data points to collect, such as wind speed, wind direction, temperature and humidity. “Dogs are being used for all kinds of interesting applications, but there’s also some skepticism or criticism, because it looks like magic,” she says. “As a scientist, it’s really an exciting opportunity to quantify the efficacy of this as a tool to help manage avian botulism.”
With 30 days of data collection complete, Reynolds is hopeful. “Field observations show a lot of promise. You can see the dogs are thorough. During training, they do a good job at finding carcasses we hide. I think they’re going to be an effective tool.”
Because a botulism antitoxin can be administered to sick birds, if dogs continue to be deployed in Hanalei, the logical next step might be to train them to find diseased birds—before they die. It’s not an outlandish idea.
We’ve known for years about dogs’ calming effects on humans. A landmark study revealed back in 1980 that one-year survival rates of heart attack patients were significantly higher for those with pets. Since then, dogs have been trained to alert their humans in advance of an epileptic seizure or significant drop in blood sugar for those with diabetes. Dogs are also being studied for their ability to sniff out breast, lung and prostate cancers. Dina Zaphiris, founder of the nonprofit In Situ Foundation in California, is dedicated to teaching dogs to screen for this work. It’s done in a laboratory setting using exhaled breath condensates, blood or urine samples lined up at dog level. Dogs work the bar like we might handle a flight of wine, sitting next to or pawing the one with cancer cells. Their reward: a food treat. Johnson, Solo’s human, was certified by Zaphiris. She shares Solo’s work on Instagram at @conservationdogshawaii.
It seems there’s no shortage of ways dogs can work on our behalf. Last year, a group in England launched a two-year research study to determine whether dogs might be able to detect early-stage Parkinson’s disease. Meanwhile, a springer spaniel in Canada is sniffing out Clostridium difficile, a highly infectious bacteria. In 2013, Zaphiris flew to Maui to train a group of a mix of five Labrador and Golden retrievers to detect E. coli, a bacteria present in urinary tract infections. She was brought in by Assistance Dogs of Hawai‘i’s Maureen Maurer. Eventually, 687 samples in a double-blind trial were conducted with the help of Clinical Labs of Hawai‘i and Kapi‘olani Medical Center. All dogs had a greater than 90 percent specificity rate in the tests; the study was published by Oxford University Press in the journal Open Forum Infectious Diseases.
Back in the taro fields of Hanalei, winds are gusting from 4.5 to 14.5 kilometers per hour, blowing in from due north to due west and all points between. Solo is in his confident sit position. The duck he’s snorted out on our behalf is a training aid—a plant. Because of the unique topographical terrain, Johnson has to train Solo to give two alerts: the first on the dike as near to the find as possible, and a second right next to the training aid—in the mud. Johnson gives Solo his command: “Find it,” she says, and he jumps down into a fallow square, mud spattering the underside of his light-colored body. A moment later he’s standing next to his training aid, looking up at me—the only two-legged animal wearing rubber boots—as if to say, “What’s taking you so long?” I jump in right after him and give him his reward—chunks of raw pork. Then, he’s ready to start searching again.