Using their extraordinary sense of smell, dogs undergo intensive and extended training to detect human remains – a skill that can lead to convictions and closure

A YMCA summer camp is a strange place to be at 8:30am on a cold fall morning.

The blue-painted buildings stand deserted now that summer has passed; most of the buildings are locked up tight with huge metal padlocks. Old hinges shriek with each gust of wind that catches them.

When the first SUV makes its way across the grounds, the gravel shifts and crunches. Seven more cars follow and park by an abandoned sports hall. As the car doors slide open, one German shepherd after another jumps to the ground and the noise begins. Deep barks fill the air.

These are the dogs of the New Jersey Rescue and Recovery K-9 Unit.

Two of the 11 canines are cadaver dogs. Also known as human remains detection dogs, they have been trained to smell death.

Specifically, the dogs are trained to smell decomposition, which means they can locate body parts, tissue, blood and bone. They can also detect residue scents, meaning they can tell if a body has been in a place, even if it’s not there any more.

In October 2013, a jury in Illinois convicted Aurelio Montano, 58, of the first-degree murder of his wife, despite the lack of a body, due in part to evidence provided by cadaver dogs who detected the scent of human remains on a rug.

A puppy in training at the Penn Vet Working Dog Center. Photograph: Tracy Darling

The exact numbers of cadaver dogs are hard to come by, but Marcia Koenig, one of the founding members of the American Rescue Dog Association, estimates that the United States has more than 500 volunteer-led canine search teams, although there are no figures for law enforcement-owned cadaver dogs.

For these dogs, finding bodies is not an innate ability but the result of intensive, dedicated training paired with their natural, instinctive abilities: high stamina, focus, obedience and, specifically, the prowess of their noses.

Most canines take between 18 months and two years to become fully fledged cadaver dogs. While the majority are Labrador retrievers or German shepherds, for most handlers the breed of dog is far less important than finding a dog who has a good hunt drive, strong nerves and confidence.

A dog’s sense of smell is estimated to be somewhere between 100 and 1,000 times greater than a human’s, depending on the breed. But despite their formidable noses, these dogs still need assistance, direction and training to reach their full potential.

The Penn Vet Working Dog Center does exactly that. Founded in 2007 and part of the University of Pennsylvania, the training centre and research program is dedicated to helping advance the success of working dogs.

Canines work eight hours a day, Monday through Friday. When puppies are about eight weeks old, they begin to learn the broad range of skills necessary for a successful working dog. Graduation day comes when the puppies are about a year and a half, at which point a major is picked for each dog, and they are sold for anywhere between $6,000 and $10,000.

The center’s graduates have gone on to work in a variety of fields, including narcotics detection, urban search and rescue, explosives detection and diabetes detection.

The main room of the center is part training hub, part office. The few desks are outnumbered by the dog-sized obstacle course. Ladders and balance beams crisscross the room, and ramps and walkways vary in material and texture: metal, wood and what looks like sandpaper. Tin cans dangle from strings and bright yellow plastic tube tunnels, the type kids play in, snake around the place.

The idea of the setup is to get the puppies accustomed to the variety of noises, textures and surfaces that they’ll face on the job.

“These dogs literally save lives, so it’s important they get trained properly,” explained Judi Berke, one of the center’s volunteer coordinators.

Notes on whiteboards on the walls list the dogs and their proficiency in crucial basic skills: obedience, agility, search, direction and control.

Every few minutes, the noise of wailing sirens drowns out the barking. “Nothing bad’s happening,” promises Patrica Kaynaroglu, one of the training managers at the center. Its purpose is to familiarize the dogs with the noises they will be encountering in the line of duty.

Scent training at the Penn Vet Working Dog Center. Photograph: pennvet

Outside, across the parking lot, is a 240,000 sq ft abandoned DuPont laboratory that is used exclusively as a training ground for the Penn Vet’s canine students.

Within, a morbid exercise is taking place: cadaver scent training.

Walking through the heavy double doors, the smell is overwhelming.

Upstairs, 15-month-old Don is training with his new partner, officer Paul Bryant of the Philadelphia police department. Don, an energetic German shepherd, and Bryant have been a team for six weeks, and they’re still getting to know each other.

On the command “Find Fred” Don is off.

“Find Fred” is an expression coined by Bryant. “With cadaver [work] the family or public is always around,” said Bryant. “So to be more sensitive I came up with ‘Find Fred.’ I thought this was a little more sensitive than ‘Find the dead guy.’”

For a newbie, Don is pretty good at finding Fred. He runs around, slipping and sliding across the laminated floors and darting into one of the empty rooms where the training material is hidden.

In another room, the scent is so overpowering that Don doesn’t know where to start. He stands in the middle of the room and looks to Bryant for guidance but he can’t give any hints. Instead he walks Don through the room step by step; they check the broken water fountain and along the walls. After a few minutes of scouring the room, Don is under a desk and barking at a wall panel. There’s a placenta hidden behind it.

According to Bryant, the Philadelphia police department uses their cadaver dogs on an as needed basis. While the amount of work for them varies, some years have as many as 20 callouts for the cadaver dog teams. Bryant explained that searches are far more efficient when using a cadaver dog; they allow the police to cover a larger area at a faster rate than searches using police officers alone, while also freeing up manpower.

“The reason I chose cadaver was for closure for families,” said Bryant. “For me and my partners it’s all about closure.”

Scent training at the Penn Vet Working Dog Center. Photograph: pennvet

Back in New Jersey, the team is a civilian-led group headed by Donna Hreniuk, who has more than 25 years experience as a canine handler. Her dog is Sabre, a huge nine-year-old black-and-tan German shepherd, and he’s very good at his job.

“I love working with dogs, especially in detection work,” said Hreniuk. “One of my first searches involved the drowning of a young man. His mother and sister were on the edge of the lake desperately watching us work the dogs and I could hear [the mother] say, ‘I just want a body to bury.’”

The moment was a defining one for Hreniuk who, echoing Bryant’s sentiments, realized that the best thing she could do for a victim’s family was to provide that kind of closure.

Another search that sticks out in Hreniuk’s mind was in Slate Hill, New York. A farmer’s dog brought the body of a baby to his backyard. The farmer reported it to state police and Hreniuk and her dog were asked to search for more evidence. “We were told the body was missing a foot, so I imagined that was what we were looking for.

“It was a cold day in February, and snowing pretty heavily. I was finishing my search area near a dump that was on the farm property. My dog, Remy, showed interest in an area and finally pinpointed the source and pulled up from the snow a clear plastic bag that had blood in it,” said Hreniuk. She radioed for the police who were waiting in the farmhouse. In the meantime, Remy kept working through the snow, and found some type of patterned material with blood on it. “Since it was evidence, I didn’t touch it. The blood was confirmed to be human at the scene.”

Now, on this chilly Saturday morning, the abandoned summer camp is the training ground for Sabre and the rest of the team. For these dogs to be able to locate all types and ages of human remains, it’s imperative that handlers use an assortment of training aids to expose the dogs to as many kinds and stages of decomposition as possible. These aids often include human bone, blood, tissue, used gauze, liposuction material and even teeth.



The door to the dining area is missing its padlock and serves as the perfect hiding place for an innocent Tupperware container. Inside is a femur. Once the bone has been stashed in a corner cupboard, the door is closed, the building is vacated and Sabre is let out of his holding crate to begin his search.

Sabre moves purposefully in the right direction almost immediately, then hurries back and forth between the camp’s huts trying to catch the strongest scent from the hidden Tupperware container. When Sabre reaches the dining building, he weaves up the pathway with his nose to the ground and ears pricked, and scratches at the door. Hreniuk intervenes only to open the door and he continues his search.

He checks the cupboard once then goes back for a second sniff; he pauses and looks at Hreniuk who gives nothing away. Human spectators stay dutifully silent to avoid giving any inadvertent clues.

He scratches at the cupboard door and barks at Hreniuk once, twice, three times. His barks are his trained indication, letting Hreniuk know that he has found what he’s looking for.

Sabre is an old pro. His reward? A tennis ball.