How Scat-Sniffing Dogs Revolutionize Wildlife Research

Few people understand the value of turds better than wildlife biologists. From scat, wildlife biologists can learn just about everything they need to know about the animals they study and how they live. Biologists can extract fecal DNA to understand the movement patterns of individuals across the landscape. They can compare that DNA to other poop samples to derive the relatedness of individuals in an area. They can dissect the poop to determine an animal’s diet and scour it for signatures of parasites and diseases. They can even use fancier techniques to determine the presence of reproductive hormones and environmental contaminants.

It’s no wonder then that, in a time of complex conservation problems that require innovative solutions, poop has emerged at the top of the biologist toolbox. These studies have been conducted for nearly every animal with conspicuous excrement, and have led to extraordinary feats like the recovery of the river otter across its native range, finding cryptic weasels and mink in the Florida Everglades, and understanding wolf, caribou, and moose dynamics in the tar sand region of Alberta. It’s a strange subject to think about, but in terms of biology, poop paints a picture, and biologists can read that crap as if it were a book about the animal’s life. The hard part is finding it, and that’s where dogs like Pepin come in.

From Wolves to Conservation Stewards

The relationship between man and man’s best friend spans back at least 30,000 years when humans first began messing around with wolves beside the campfire. We’re all familiar with the story. Humans kill game, roast it on the fire, wolves catch a whiff and move in close, and humans eventually toss over a scrap or two of meat. Rinse and repeat that process over a millennia, and bam! Now you have dogs, existing in a mutualistic agreement that they’ll do what we want them to do and we’ll continue to feed them.

We leverage that relationship with our gun dogs. Whether it’s flushing grouse or retrieving ducks, we teach our dogs what we want them to do, and the dogs understand the agreement. Rewards range from little treats, head rubs, and in the case of scat-sniffing conservation dogs, a quick game of fetch with a tennis ball. The more natural the task, like carrying something in their mouth or blood trailing a deer, the easier it is to teach. These basic skills are etched into our dogs’ ancient wolf genetics, and so is sniffing out scat.

“You know, carnivores, they’re not just defecating to defecate. They’re leaving signals for other carnivores out there on the landscape,” Pete Coppolillo, executive director at Working Dogs for Conservation said. “And here we are, living with a carnivore for the last 30,000 years that’s equipped to find and interpret those signals.”

Dogs understand the poop language, and we don’t. That’s why biologists have been hijacking their senses to detect wildlife since the 1890s. It all began in New Zealand where dogs were trained to sniff out two flightless birds, the kakapo and kiwi, in an effort to find and move those birds to a nearby island without predators.

Since that time, detector dogs have evolved in utility. Overseas, detector dogs have been used to sniff out poached elephant ivory and pangolin scales. In Brazil, biologists trained dogs to locate cryptic giant armadillos and anteaters. Detector dogs even trudge through the Chesapeake Bay estuary, where they sniff out scat as a part of the highly successful nutria eradication effort. In that instance, scat-sniffing dogs post higher detection rates for finding nutria than both hair snare and camera trap methodologies combined.

Now, Working Dogs for Conservation (WD4C) stands at the forefront of most of this work. They’ve produced some of the finest scat-sniffing dogs in the world and deployed them on conservation projects across the globe. Pepin, whose littermate was a part of Seal Team 6s takedown of Osama Bin Laden, joined the WD4C team back in 2007. Here, the once-rejected police dog is among the elite. During his work in the Centennial Mountains, Pepin helped clear the path toward gray wolf delisting in 2009. One of the criteria for delisting gray wolves from the Endangered Species Act was the presence of genetic connectivity between the Idaho and Greater Yellowstone wolf populations. The Centennial Mountains, which run east to west, provide a habitat corridor between those two populations. Nobody knew if wolves, grizzly bears, black bears, or mountain lions, used the Centennials to cross over between populations until Pepin was sent up there with his extraordinary nose to find out.

At WD4C, Pepin is joined by other scent-sniffing dogs. Wickett is a rescued Labrador retriever mix trained on 26 scents. Finny, another labrador retriever specializes in black-footed ferret detection and kit fox scat, and Tia, a German shepherd that can smell emerald ash borer beetles and brook trout in a stream. Together, these dogs make up just a small portion of the WD4C roster, which now boasts dozens of adopted dogs specially trained for wildlife work.

How to Make a Scat Dog

It turns out dogs that have been exiled from home life, abandoned, or otherwise unwanted, are among the best candidates for complex conservation work. WD4C, for example, prides itself on adopting most of its dogs from shelters.

“We don’t select for particular breeds, we select for behavioral characteristics,” Coppolillo said. “We’re looking for those ones that are like, ‘_I know there’s a ball out there somewhere, and I’m going to find that damn thing no matter wha_t.’”

Once the dogs demonstrate that they have the raw instincts and drive necessary for long, arduous detection work, they pair them up with a trainer. Essentially, the dog and the trainer become roommates and best friends. Dogs move in with their trainers; they work together, play together, eat together, and sleep under one roof. The trainer and dog learn to communicate through body language and a variety of verbal and non-verbal cues. Eventually, they build a relationship founded on trust and understanding. It’s that kind of close-knit emotional connection that not only brings out the best in the human-dog relationship but also overcomes struggles in the field.

“We had a cheetah defecate in a tree in Zambia,” Copollio told MeatEater. “And cheetahs aren’t supposed to climb trees or mark on trees. Our dog alerted from 600 meters away, but then he would get there, and that odor would disappear because it was up in the air. He was walking right under it.”

That’s the kind of situation where the relationship between the dog and handler becomes crucial, Copollio explained. In this instance, the dog’s handler read the body language, dissected the situation, and determined that there was cheetah scat present, just not on the ground.

WD4C’s pooches are often trained on multiple scents. So, to ensure both precision and accuracy, testing occurs in a controlled, double-blind scientific setting, usually a laboratory room. In the room, dogs are presented with a series of scent trials. These trials are recorded, and scents occur on a scent wheel. One arm of the wheel has the scent and others have distractor odors. Sometimes, researchers present a bunch of odors of which none are the target. Researchers never enter the room during the trial, because human body language risks cuing the dogs even if it is unintended.

This kind of double-blind design was inspired by the story of Clever Hans. Clever Hans was a horse that understood math. Hans could add, divide, subtract, and multiply. When posed with a math problem, Clever Hans would stomp his hoof a specific number of times to specify the answer. Two plus two? Hans stomped four times. Hans grew to international fame and even hit headlines in the New York Times in 1904. Then, his story crumbled. The Hans Commission was formed by psychologist Carl Stumpf to examine the horse’s extraordinary feats. After a series of trials, the Hans Commission determined that the horse didn’t actually know math. When posed with a math problem, Hans stomped its foot until people got excited. Hans didn’t understand arithmetic, but he was a master at reading human body language to get a reward.

To make the cut, detection dogs need to demonstrate both sensitivity and specificity. Sensitivity is a dog's ability to detect present targets, and specificity is the capability of the dog to not present false positives. If they pass both sensitivity and specificity trials with a success rate over 90%, they’re ready for the field. Better yet, if they succeed in an individual trial, trainers reward them with a treat. At the end of it all, they may even get the big reward—the tennis ball. Biologists at WD4C find that toy motivation is greater than any other enticement among their dogs. Throwing a tennis ball sends their dogs into a frantic tornado of excitement. “That’s their paycheck,” Coppolillo said.

The Value of Turds

Bighorn sheep haven’t had it easy since Europeans settled in the Americas. Prior to the 1800s, bighorns could be heard bucking horns in a nearly unbroken chain ranging from the deserts of Mexico, the American West, and up into Canadian Rockies. Isolated herds can still be found in parts of these areas, but they exist in small disjunct pockets—a result of human-induced factors, such as habitat loss, water source degradation, and the introduction of a pathogen called Mycoplasma ovipneumoniae (MOV).

MOV infects farm sheep and causes no real harm, but once bighorn sheep contract MOV from their domestic counterparts, they experience persistent pneumonia that can kill off a whole herd. This is a problem because biologists tasked with bighorn sheep management often translocate individuals to restore herds in suitable habitats, and you can’t move a sheep infected with MOV, or else you risk spreading the disease to uninfected herds. So, biologists monitor MOV infections by riding in helicopters and shooting nets at bighorns from above. Captured sheep get put into a trailer. Then, they take a disease sample, FedEx the sample to the disease laboratory, and wait around until they receive the results. The process is incredibly expensive and time-consuming, but necessary to keep bighorn sheep in the American wild.

Organizations like WD4C have worked hard to find a better solution. In recent trials, WD4C’s dogs demonstrated the ability to discriminate between infected and uninfected farm sheep by scat smell alone. In theory, they should be able to do the same with bighorn sheep pellets. If it all works out, biologists will no longer need to ship out biological samples via snail mail across the country. Instead, their detection dogs can catch a whiff of scat and immediately inform whether the sheep is infected or not. Coppollio and his team hope that their dogs will soon be deployed in the field, where they can revolutionize MOV monitoring, improve efficiency, and save biologists both time and money.

“Most humans search with their eyes. So, if it’s not visible or if it looks like everything else around it, it's a whole lot harder. But olfactory searching is very different,” Coppollilo said. “There are all kinds of new frontiers, like CWD. Detecting it, mapping it, mitigating it—there’s a huge role for dogs to play in that.”

Disease detection, genetic modification detection, and countless unforeseen applications lie in the future for scat-dog work, Coppollilo explained. According to Coppollilo and his team, we’ve barely scratched the surface. For example, nobody anticipated that Pepin would be able to sniff out year-old grizzly scat submerged underwater to inform carnivore movement across the landscape until he did in the early 2000s. Nobody thought that dogs could sniff a stream and tell biologists what type of fish live there. And nobody thought to have dogs sniff mounds of sheep pellets to detect diseases until they did.

It seems as though the future of scat-sniffing dog work will be dictated by the conservation issues at hand, and the more we task detection dogs with the more we’ll realize that their olfactory systems are tuned into the exact things we need to know to conserve wild things and wild places.

It’s strange to think that in a time where increasingly complex conservation problems require more and more innovative approaches, scat dogs offer a simple solution, but Coppollio sums it up clear as day.

“The value of turds,” he said, “keeps going up.”