Synopsis: Search dogs will follow a scent for miles and even put their lives in danger looking for survivors of mudslides and building collapses. How do they do it, and why? We talk to a search dog owner and trainer about these amazing animals, the physiology that helps them hone in on a single scent, and why they will work for hours in horrid conditions for their handlers.

Host: Marty Peterson. Guest: Cat Warren, cadaver dog owner and trainer, author of the book, “What the Dog Knows: Scent, science and the amazing ways dogs perceive the world.

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What the Dog Knows: Navigating the world through scent

Marty Peterson: We’ve all see the pictures of some disaster or another – a tornado, building collapse, bombing – and the search and rescue teams that show up on the scene before the smoke has cleared. Many of those searchers use dogs to help them sniff out the scent of humans trapped beneath the rubble. The dogs climb and jump from one timber or block of concrete to another, seemingly without a care about their own safety. Their focus is razor sharp – nothing seems to deter them – until they find a survivor or lost soul and signal their handler. It’s a sad, but often rewarding, line of work and we wondered what it takes to be a search dog, and how they do their jobs. Cat Warren knows. She’s a professor at North Carolina State University and a cadaver dog handler and trainer. She’s also author of the book “What the Dog Knows: Scent, science, and the amazing ways dogs perceive the world.” She was fascinated about the topic so she decided it was time someone wrote about it….

Cat Warren: My dog got me interested in the topic, and you know it’s funny because I started doing this search work with him and for years I resisted writing about it because I, I was a little bit superstitious. I was having such fun training him and starting to do searches with him and I thought if I try to write about it I’d kind of ruin it. But there was a point when he turned six years old and I looked at him one night and I thought if I don’t capture him and my fascination with the general topic it would be kind of a shame. And that’s when I turned to my husband and I said, “You know what? I think I want to write about this after all.”

Peterson: The first question anyone asks about search dogs is how they can find a person buried beneath rubble, or in the case of Warren and her dog, Solo, in old, Civil War cemeteries?

Warren: We are still learning more about it every year. And there’s still a lot of mysteries about it, but we do know of course that the mammalian brain actually got bigger partly because of the olfactory regions. There’s a real link between that. And then dogs process scent a little differently than humans do. And for instance, dogs are able to do stereo with each nostril. So one nostril can have a scent coming in on one side and the dog can bring it in on one side but not on the other, and that really helps, for instance, with directional stuff. And then the way scent flows over these little terminates, they have so much more processing in their heads than we do. And really it’s fascinating.

Peterson: Many search dogs are German Shepherds, like Warren’s dog Solo, or the iconic searcher – the bloodhound. Do certain breeds of dogs have better sniffing abilities than others?

Warren: To say that one dog is better than another, you’d really be making it up at that point. The bloodhound – all the stuff you hear about those long ears and those wrinkles that helps them capture scent – there’s actually no evidence for that. It does make a nice story, right? But we have no clear evidence that a bloodhound is better at following a trail than a well-trained Laborador.

Peterson: Extreme focus is what allows scent detection dogs to do amazing things….like single out one person’s scent in a crowded shopping mall. Warren says that live human scent is extremely complex, and it takes a very well-trained animal to distinguish one human from another…

Warren: You are asking a dog “I want you to find this human as opposed to all the others, and I want you to ignore any trails that cross this and follow just this trail.” And it really takes an enormous amount of training. And I remember going back in the history books, and Robert Boyle who was a very early chemist writing about watching a bloodhound do this. You know he was writing in the 18th century and this dog going through this crowded marketplace and finding this person in a room, like a second-story room. And I’ve watched this with really good tracking or trailing dogs, and it’s astonishing what they can ignore. Part of it is is not just “here’s a sock, go follow this trail.” It’s also this ability to ignore everything else that gets in the way of that trail.

Peterson: Warren and her dogs search out bodies that have been buried for decades in old cemeteries where the scent isn’t wafting in the breeze, but buried deep underground…

Warren: We don’t know all of what remains, but the fact is that we do know dogs are able to detect remains that go back hundreds of years. And what the volatiles, in other words, what is coming off very old bones or even in the dirt, is a little bit of a mystery, because let’s acknowledge it’s not very strong at all, but there’s enough there. And I’ve had both my dogs, the one that I’ve go in training now but Solo as well, working in cemeteries, and I’ve watched so many dogs work cemeteries that it is fascinating that they can pick up on such faint scent, but they do.

Peterson: The ability to focus and detect live or dead human scent is amazing, but why do they do it? What makes dogs want to spend hours in the cold or the heat, putting themselves in danger of injury or death?

Warren: They want their toy. I know that sounds so simple, but the fact is that dogs work that solidly because they love doing it. It’s the same reason a border collie will herd sheep for hours. It is something both rewarding for the dog and the anticipation of an extra reward makes them continue to work. You know, Solo, whom I retired a year ago when he was 10 and he’s now 11, he still absolutely goes nuts if I bring out his tug toy. He screams and dances around and tries to grab my pocket. He will work for just unlimited amounts of time, I don’t let him, in order to get that tug toy reward at the end.

Peterson: We’ve heard what the dog needs to do its job well, but what kind of trainer does it take to make a willing animal into a scent-detection dog?

Warren: The excellent handlers that I see have a number of things going for them. I think they’re enormously patient and low-key. I think that they bring a whole set of tools to the notion of training of any particular dog. They don’t come with a sort of all-or-nothing view. “If I don’t get through to this dog by doing this system, by god that dog’s a failure.” Good handlers are able to sort of adjust their game.

Peterson: They also have to know how to have fun with their dogs, and how to reward them for their work. Because after all, that’s why the dog does the work in the first place. Warren says that scent games are great for anyone who has a dog as a pet, and for inspiration you can take a look at some of the ways handlers train their dogs on her website at Cat You can also find more information there about her book, “What the Dog Knows,” available at stores and online. And you can visit our site at Viewpoints Our show is written and produced by Pat Reuter. Our production directors are Sean Waldron, Reed Pence and Nick Hofstra. I’m Marty Peterson.