His seeker is Sirius, a 14-month-old yellow Labrador retriever bred for his hunting instincts. Since he was only eight weeks old, the dog has been taught to track down human scent.
Sirius is a member of the first class to graduate from the new Working Dog Center at the University of Pennsylvania. The center will hold a ceremony Tuesday to mark its one-year anniversary and the dogs' completion of the training program.
Named for the only search and rescue dog killed at the World Trade Center on 9/11, Sirius will soon join either a police department or some other investigative team.
Depending on their individual talents and personalities, his six classmates, also named for 9/11 dogs, will be sold for $10,000 each to law enforcement and security forces or private individuals. For the rest of their lives, the dogs will help detect cancer, prevent diabetics from lapsing into comas, locate explosives, uncover drugs, and find people who are buried in collapsed buildings or lost in the wilderness.
The idea for the center came to Cindy Otto nearly 10 years before she was able to make it a reality. A veterinarian with a Ph.D. in veterinary physiology, Otto, 52, specializes in critical care and emergency medicine. During 9/11, she helped care for the dogs that scoured ground zero, looking for bodies.
During her 16-year tenure on the federal urban search and rescue task force in Pennsylvania, she saw a decline in the quality and availability of dogs needed to perform critical tasks.
"There are only about 180 of these dogs nationwide," she said, giving a tour of the facility she now directs. Traditionally, most of the dogs came from other countries, primarily in Eastern Europe.
But as demand for detection dogs has increased, high-quality breeders have had trouble keeping up, she said.
"China and India use search and rescue dogs now. And they're needed here not just to find drugs and explosives, but bedbugs, too. Conservation groups use them to find invasive plant species or pet pythons that have been set free in the Everglades."
Some of the new breeders who have entered the market, she said, are less careful about maintaining the exacting standards needed to produce reliable dogs.
Otto and her colleague, Gail Smith, a veterinary orthopedist, had mused about the need to breed and train the dogs domestically. In 2004, Otto came up with a rough plan for a center.
"The only problem was, I had no money and no space," Otto said.
She and a few of her colleagues took courses at the Wharton School to learn how to run a small business. In 2011, several false starts later, she learned that the University of Pennsylvania had bought an old chemical research facility in Grays Ferry.
With help from the Penn administration, and a PowerPoint presentation at the Westminster Dog Show, she received $500,000 from donors and grants - enough to refurbish the buildings and hire staff.
The first seven puppies, donated by top breeders in the United States, arrived Sept. 10, 2012. Their lessons began immediately - which was unusual, said Annemarie DeAngelo, director of training.
Traditionally, it was thought that if puppies were taught obedience too early, it would interfere with their drive, DeAngelo said. "But we learned that is not true at all."
All of the dogs - the original seven and an additional nine that have arrived over the course of the year - have responded beautifully, DeAngelo said. And by observing the puppies from such a young age, the trainers have been able to identify and nurture their innate skills.
From the beginning, Sirius proved to be a natural hunter.
About 100 yards from where Dougherty is hiding, a handler tells the dog to sit. Sirius waits until the leash is unclipped and he hears the command, "Find!" He flies across the yard.
He stops to sniff for a split-second at a barrel where Dougherty had been, then homes in on the one where he is now.
Barking loudly, Sirius peers into the hole in the lid and is quickly rewarded. Dougherty pokes his hand out, offers the dog a heft of rope, then shimmies into the sunlight to play a rugged game of tug-of-war.
"Thank you, bud," says Dougherty with soft, gruff gratitude. "Thank you for finding me."