Humans have relied on dogs’ excellent sense of smell for centuries. The animals have been used to detect diseases like Covid and find drugs and bodies. But in the last few years, the U.S. has faced a shortage of canines trained to sniff out bombs—an issue that has gotten worse because of the pandemic.
Cindy Otto, the executive director of the PennVet Working Dog Center at the University of Pennsylvania, has been warning of this shortage since at least 2016.
"We rely heavily on procurement of dogs from other countries,” she testified before the Senate Homeland Security Committee six years ago. “By outsourcing our national security requirements, we give up control of the type of dogs, the health of the dogs and the early training of the dogs. We also are at risk for supply interruption due to politics, disaster or disease."
Covid-19 negatively impacted both the procurement of trained dogs by the U.S. and the breeding of dogs, according to Wired.
The federal government employs a total of 5,159 dogs (as of February 2022) to perform a variety of tasks that range from detecting explosives on Amtrak trains to sniffing out disease. But only seven percent of these dogs come from the United States, and the rest are mostly imported from Europe, per the American Kennel Club. When the pandemic hit, dogs were a hard-to-find commodity.
“The canine nose is the best technology we have for locating explosives, so we need to have a very consistent and high-quality source of dogs,” Sheila Goffe, vice president of government relations at the American Kennel Club tells Wired’s Lily Hay Newman. “We used to talk about, ‘Well, what if there’s a global crisis or geopolitical issues, we’re not going to be able to get all of these dogs we’re importing from Europe,’ and then it happened.”
Estimates put a dog's nose anywhere from 10,000 to 100,000 times more sensitive than a human’s. They have about 300 million olfactory receptors in their snouts, compared to our 6 million. And the structure of their noses is different: A fold of tissue splits breathing and smelling into two separate actions, whereas ours combines both together. When they exhale, the air comes out slits in their noses, rather the way it came in, allowing them to sniff in a more continuous stream of air. Their brains differ from ours too: The part that analyzes smells is proportionally about 40 times bigger.
These biological structures mean dogs can smell substances at concentrations of one part per trillion, the equivalent of a drop of liquid in 20 Olympic-size pools.
Dogs aren’t the only animals with a superior sense of smell. Elephants, rats and jackals all have excellent noses. For obvious reasons, elephants aren’t a top choice for finding explosives, but rats actually have been used to detect landmines. Proponents say they may be cheaper to train and more agile at maneuvering in tight spaces.
A sniffing superpower is only part of what makes a good explosives-detection animal. They also must have the right temperament and be able to work effectively with humans. When searching for the best dogs to find bombs, researchers look for canines with a strong desire to work, be friendly towards humans, and have a lack of fear of environmental factors like elevation and loud noise.
Breeding and training dogs with the perfect combination of traits can be expensive. The training of a passenger-screening dog and handler for the Transportation Security Administration can cost about $46,000, wrote Clayton Dyer for Insider last March.
One solution experts propose to deal with the shortage is to increase the number of trained dogs bred in U.S. Programs. Auburn Dog at Auburn University is working towards making that a reality.
“There is not yet a road map to a complete solution to domestic sourcing for detection dogs,” Skip Bartol, associate dean of research and graduate studies at the Auburn University College of Veterinary Medicine, tells Wired. “But what we are trying to do is establish best scientific practices—everything from making sound genetic decisions about the breeding of detector canines to their development as puppies to how early environment affects their lifelong potential.”