Training A Scent-Detection Dog

The education of a scent-detection dog.
By Cat Warren, September 2016
Jaco is a two-year-old German Shepherd from the Czech Republic.
Jaco gets a grip on a section of rubber blast hose, which is used to train dogs in bitework.
Warren and pupil

Jaco pulls me hard past the cars in the driveway, slowing to run his nose across the seam of each trunk. The Prius, the Leaf, the old Mercedes, our Honda Civic covered with road dust and acorns. It’s an obsessive-compulsive habit from his early adolescence in the Czech Republic, where he had started to learn to detect explosives. I keep him moving. Someday, however, he may have to search car trunks for the scent of human remains. Because I’d like him to do that, I don’t actively discourage his vestigial nose sweeps.

Jaco is two years old, a compact sable German Shepherd with a stiff, cream-colored ruff of fur encircling his neck. He looks like a cross between a wolf, a tortoiseshell cat and Queen Victoria. I first met him outside a working-dog vendor’s kennel in North Carolina. His name was Jack then. He was 17 months old, recently flown in from the Czech Republic. Many U.S. law enforcement agencies get their detection and patrol dogs from Europe, either directly or via vendors who go over and bring back dogs they think show promise for law enforcement or for ring sports such as Schutzhund. I had decided to go the same route for my next cadaver dog.

I had never considered bringing home an adult German Shepherd before. I’d always started with fuzzy pups with milk teeth and elastic brains ready to be molded. This time, we’d get a dog who was already a bundle of muscle, with huge ivory fangs and a mind of his own. My husband, David, and I talked a long time about this unfamiliar dog-acquisition route. David asked me uneasily how a dog bred and raised for law enforcement or military work might fit into our small household and my world of volunteer search and rescue. Would the dog bond with me? With David?

Of course, I assured him breezily. Look at all the cops who have dogs they adore, and vice versa. They rarely get them as pups. I didn’t tell David that I knew some cops who greatly respected but didn’t love their dogs. And while rare, I’d seen a few cops who were afraid of their own dogs.

When the vendor brought Jaco out to meet us, he eyed me obliquely, then walked stiff-legged over to David, stood at his side and growled gently at him. David stood still and avoided making chirrupy, encouraging noises. The vendor wasn’t disturbed in the least; she approved of that wariness. That was the East German border patrol lineage coming out.

This particular dog, the vendor told me earlier via text, was “a lot of dog,” “a working fool.” Maybe too much dog for me? I needed a dog to work alongside me, not climb up the leash after me. I was a volunteer who wanted a dog to find dead people, not seek out suspects. I didn’t need a dog who considered every stranger, or my husband, as a potential bad guy.

But the qualities one looks for in any scent-detection dog, whether for law enforcement or volunteer purposes, are similar: A dog with drive. One who can hunt for scent for hours and not give up. Those qualities can be easier to find in the thousands of young German Shepherds, Dutch Shepherds, and Belgian Malinois brought over each year from Europe to populate law enforcement K9 units in this country. These dogs—usually with ribs showing as a result of pacing in their kennels, being chronically underfed and then shipped long distances—arrive with the stench of kennel urine. They don’t arrive with cheery notes from their trainers. Or warning labels.

With imported “green” working dogs, it’s hard to know exactly how they were trained, what kind of health they’re in or what sort of personality they have. They all seem to have good noses (and a love of launching at a bite sleeve or a Gappay ball). We didn’t know if Jaco was housebroken or if he’d ever been in a home. We didn’t know if he was going to retain his suspicion of David.

Jaco’s early training had clearly involved bitework. When I brought out a section of rubber blast hose a few days after we brought him home, his teeth chattered with eagerness; he was trying to cap his own drive with that chatter. Then, he levitated and grabbed it, jolting me hard. He saw a jute bite sleeve at a training venue and dragged me to it, head low, gaze fixed, digging his nails into the concrete floor to get to it. The first few times I brought him into a warehouse, he was sure it was to play the bad-guy game. He glanced around quickly, ears pricked, forward on his toes, looking for a decoy skulking in a corner.

About a week after Jaco came to live with us, one of our neighbors saw him gazing at me with his enigmatic umber eyes. Leaping across species and gender boundaries, she declared, “He looks at you just like he’s a mail-order bride!” But I didn’t want Jaco for his gaze—which, by then, we were pretty sure wasn’t sociopathic—I wanted him for his nose. And I wanted that nose up and running as soon as possible.

I had spent eight years searching for the missing and dead with Solo. Only months after he died at the age of 11, we got word from the vendor that she had a good working dog prospect for me to assess. Part of me wanted a puppy, but I also wanted a dog who was sufficiently developed to allow me to see if, as an adult, he would have what I needed: the drive and mental stability to search for hours in bad conditions.

Not unlike a vaguely suspicious spouse who realizes it might be good to know more about his mysterious mail-order bride, I did an Internet search and stumbled upon an early video of Jaco trying to find a PVC pipe filled with Semtex (a plastic explosive notoriously popular with terrorists) under one of several milk crates. I say “trying” because Jaco wasn’t very good. I could see both his sincerity and his hesitation. He was 14 months old then, with tufts of hair going every which way, like a teenager who had just fallen out of bed. Is this what you want? He kept glancing at the trainer, and then back at the three plastic crates. One had the pipe underneath. He offered a tentative down next to it. It looked as though he hadn’t bothered using his nose. He was smart enough to cue off the trainer, who kept her foot planted on the positive crate.

The video gave me pause. I had expected a bundle of muscle and drive with a superfine nose, all parts installed and in working order. I wondered if this was why Jaco had been sent to the United States.

Still, I wanted to get going. I wanted to fill that handsome sable head with new marching orders, a world of toys and treats, a rich vocabulary, and so many new people he would soon realize how wonderful humans were (even if I knew better). In my American ignorance, despite all the evidence that he was mostly goofy and playful, I wrongly assumed that he’d had a puppyhood devoid of play and stimulation. I wanted to teach him to fetch and tug, and sit, and down and heel.

Most importantly, I wanted to expose him to the entirely new range of odors he would need to recognize to start searching for the dead. Those odors are as complicated as people; forensic scientists have identified at least 480 volatile compounds emitted by human remains, and the list keeps growing.

As I prepared to institute my complex battle plan, a more experienced friend—one who had trained many more search dogs than I—stopped me and gave me advice that I hated. “Sometimes,” my friend said, “doing nothing is better than doing something.”

I’m not exactly Zen, so it took time to understand what she was saying. When her simple remark sunk in, I realized that it was the best training advice I’d ever received. Making Jaco sensitive to what I did or said, teaching him to gaze adoringly into my eyes before he moved? That was the wrong approach. The definition of “doing nothing” depends on the individual dog, but in general, it means slowing down and not tossing a dog you don’t know into a scrum of people and new situations he’s not comfortable with, flooding him instead of teaching him. It means not rushing into training that might backfire.

I backed off my ambitious initial plans. Instead, David and I cuddled Jaco. Oddly, he liked that. We taught him to get in his crate without a fuss and wait for his food rather than scrabble to get out. He learned to navigate our slippery stairs without hesitation, and to stay off the counters. He had only one accident in the house. We taught him to tolerate his nails being Dremeled without grabbing our hands in irritation. I took Jaco into tobacco warehouses and deserted office buildings, and he stopped eyeing dark corners with as much suspicion. But I didn’t invite some of my wonderful but voluble friends over to meet him, and I didn’t parade him around the farmers’ market.

I waited. We bonded. And he didn’t growl at David again. Instead, when he saw my husband, Jaco’s mouth would fall open in a delighted grin.

TEACHING OBEDIENCE TO ODOR

A month after he came to live with us, Jaco and I went to see Lucy Newton, who’s quiet and exacting. She likes dogs. And most people. Unlike me, she is settled within herself. She has a couple of decades of experience training search-and-rescue dogs, patrol dogs, human-remains detection dogs, narcotics dogs, conservation dogs. I have enough experience to have had some success, but I’ve had notable failures as well. I also had some bad habits. It wasn’t just Jaco who had things to learn.

Lucy breaks tasks down into their smallest increments, partly for the handler’s benefit, sure, but largely because it helps the dog. Her directions to me were specific and clear: Open Jaco’s crate in the car. Clip his leash to his flat collar. Clip the collar on Jaco. Don’t hurry. Gather yourself. Only then, let him leap to the ground.

A chartreuse tennis ball on a string waited on the ground where he landed. His eyes glowed, his teeth snapped and he pranced into the nearby garage, the tennis ball clenched in his jaws, its short string hanging from his mouth like the tail of a dead mouse. After four weeks of cold turkey on any toy that resembled a ball, after four weeks of bonding boredom, Jaco finally got his fix.

Lucy waited for us at the back of the large garage, standing on a platform behind a bank of eight identical plywood boxes hanging from a rail. Part of a detection-dog training system developed by K9 trainer Randy Hare, the boxes had big PVC pipes sticking out of their tops like chimneys and clear plastic covers that could be raised and lowered on their fronts. Tinny rock music blared from a radio in the corner. Jaco ignored the music. The floor was slippery. Jaco ignored that. His mouth was full of tennis ball, and he was straining at the end of his leash. He’d been ball deprived and he didn’t want it taken away from him.

Without fanfare or a single word, Lucy dropped another tennis ball on a string down one of the box’s chimneys. She made it jerk around like a psychotic puppet. The trap was set. Jaco’s eyes widened. Forget that saying about a rabbit in the mouth being worth two in the bush. So untrue. He dropped the sodden ball on the concrete, then lunged toward the herky-jerky ball in the box. I lurched along behind, trying to keep his leash loose. Lucy, a masterful puppeteer, kept the tennis ball on the string both inside the box and inside Jaco’s jaws with slow, methodical tugs. His tail wagged slowly, his eyes were slitted in ecstasy.

That particular box held more than a bouncing ball. Wafting from a hidden compartment was the scent of human remains. As he blissfully tugged, Jaco got constant hits of this scent. That’s why Lucy let Jaco bogey that ball. That’s how you addict a dog to a scent. It was Jaco’s first step in learning the most important concept a detection dog needs: “obedience to odor.”

This moment was why my friend hadn’t allowed me to teach Jaco to “watch me” or “sit” or “down” or “give” or “fetch.” Or “come,” for that matter, as important as it is. Those would come later. For a scent-detection dog, one desire should override everything else: getting to the odor, wherever it’s located. That was what Lucy was teaching Jaco with Randy Hare’s box system. Other training techniques work, too. But this particular method made Jaco’s job simple and mine even simpler: I just had to get out of his way; he could essentially teach himself. He learned that three things were connected: if he could get as close as possible to a particular odor, he’d get a ball and a fun tug.

Over the next two weeks, in two 10-minute sessions each day, I watched Jaco transform from a hesitant “Is-this-it?” dog into an obsessed “I’m-at-the-box-with-the-scent-so-giveme- my-tug-game!” dog. Lucy, occasionally a tease, would wave a tennis ball on a string in front of his face, and he’d ignore it. If it wasn’t right next to the scent, he knew the ball wouldn’t put up a fight. Lucy threw a bunch of balls onto the floor, where they lay enticingly, like sirens on a rock. Jaco, now wiser than Odysseus, ignored them. He knew those balls were a trick, that the only time he’d get a ball to fight properly was if he had his head buried inside the box that contained the scent of human remains.

Other boxes had other scents: dead squirrel, kibble, deer bone. His nose quickly rejected them to find the box that made the ball come down the chimney. Lucy put ladders and chairs and slippery cardboard in front of the bank of boxes. After worrying and thinking hard, Jaco leapt over them, then shoved them aside with his nose. And there was the plywood box containing human remains. He planted his nose there. Lucy waited several beats. So did Jaco, his head cocked, fixed, like a fox at a mousehole. At last, as he knew it would, the good tennis ball came down the chute. And Jaco got his game. I make it sound so simple. Oddly, it was.

THE GAME’S THE SAME

We took the game outside the garage, and Jaco generalized quickly. No boxes with chimneys? Never mind. They’re not part of the scent-ball-tug triumvirate. He started to find scent source in the yard, in the woods, in the warehouse, in the alley behind a large home-improvement store. He was always astonished and pleased. His head would bob up and down like one of those toy drinking birds, almost touching the source, swinging up to make sure that I was coming to reward him, bringing it down to fix his nose as close to the source as he could get. The rules never changed; the game was the same.

Of course, this didn’t happen overnight, and, like any scent-detection dog, Jaco’s a work in progress. As am I, his handler. But as Jaco learns to find the scent of human remains hung in a tree, buried in the ground, downwind, upwind, in the heat and in the rain, on short searches and long searches, I’m watching him with joy. He’s not perfect. No dog is (nor is any handler). He adores chasing insects, possibly a vestige of his past life, when he was in a kennel and bored and flies were a great distraction. But he’s learned that a live tennis ball is more fun than a fly.

He needs no command. A tennis ball on a string is waiting on the ground when he leaps out of his crate. He grabs it. We go to wherever the training search starts. I show him a second ball, he drops the first, grabs for the second and misses, and I tuck both into my pocket. This ritual betrayal is his signal to start the hunt. His eyes light up, his mouth opens and he leaps away from me. Game on. Recently, I hid training material in an acre or so of deadfall and heavy brush and mud, the kind of mess created by a flooding river. A brisk wind whipped scent through the fallen trees and debris. He’d never worked in conditions this physically challenging.

So that he couldn’t track me back, I started him in an area away from where I’d walked to plant the material. I tucked the tennis balls in my pocket and he threw his head and ran. Within a minute, he was working more than 150 feet away from me, balancing on logs at the outer edge of the pile, then working his way back in. I could see him lift his head as he found scent drifting through one side of the pile. He ran around the edge, working to get ever closer. I stood there, watching him teach himself, watching his intense focus, watching him learn a new search pattern in the jigsaw puzzle of logs and branches. I was a bit worried about this new and precarious environment. He was not.

For Jaco, the tangle of wood, wind and mud was simply in the way of the three things he wanted: Scent. Ball. Tug.

Cat Warren is author of the New York Times bestseller What the Dog Knows: Scent, Science, and the Amazing Ways Dogs Perceive the World. A professor at North Carolina State University, she is also a volunteer cadaver-dog handler.