The Canine Nose Knows

Last week, we talked about different types of search-and-rescue dogs and their different skills and searching techniques. Before we start to look at the difficulties of finding a victim in the real world, it might be useful to look at the amazing capabilities of these animals. How can a bloodhound sense a few scent molecules and use that to find a lost child? Or how can a Labrador catch a single trace of a victim buried in an avalanche or from vast distances away? The answer is actually quite simple—the canine nose.

The key to a dog’s ability to smell is twofold—the number of olfactory receptors and the architecture of the nose. Dogs have approximately 220 million receptors, compared to our own 5 million. This allows them to detect odors 100,000 times less concentrated than humans. To manage this kind of sensory overload, twelve percent of the canine brain is dedicated to smell; by comparison, humans use one percent of their brain for the same purpose. A dog’s olfactory receptors even have the infrared capability to literally smell heat. The best way to sum it up is that dogs smell like humans see: individual smells, not an overall smell (conversely, humans smell like dogs see). Where a human smells chicken soup, a dog detects cooked chicken, onions, rice, herbs and spices.

Sniffing for a dog is not actually part of their normal breathing pattern; instead it is a series of short inhalations and exhalations. Air is forced upward into the olfactory recess (pictured above in khaki), separate from the main respiratory airflow path. Due to the recessed positioning and complex folds, scent molecules are not washed out upon exhalation which allows for a concentration of scent over time. Molecules are absorbed into the mucous membranes of the olfactory recess and come in contact with the receptor neurons, which, in turn, carry the signal to the brain. An additional special aspect of canine olfaction is the ability to smell in stereo. This allows them to directionally work a scent cone and to distinguish individual smells.

Next week we’re going to look at how dogs use their amazing olfactory sense to be able to follow scent through some of the hardest of terrains, all while being confounded by air currents, turbulence, daytime heating, nighttime cooling, water, and other obstacles.

Photo credit: Rusty Clark and B.A. Craven et al

Search-and Rescue Dogs

Last week, we looked at modern working dogs and all the ways they help and protect us. Today and over the upcoming weeks, we’re going to focus in on a particular type of modern dog—the search-and-rescue dog—along with its handler.

As previously mentioned, search-and-rescue dogs are especially useful in situations where a person is missing in a large or especially hazardous area. Situations involving hikers lost in the woods or on mountains, hurricane victims, or the elderly or small children who have wandered away from home would all benefit from the amazing scenting abilities of search-and-rescue dogs.

We’ve all seen them on the news: dogs wearing bright-coloured vests climbing over collapsed buildings or running through a field or forest, searching for the lost. But how are they able to find that sole person in such a large or complex area? In the end, it all comes down to skin cells. Without our knowledge, we humans shed about 40,000 skin cells each minute, and they fall around us like a cloud, either settling to the ground around us if the air is still, or they’re caught on the downstream wind to travel significant distances. And it’s not just the skin cells dogs can smell—it’s the scent of perspiration, soap and skin care products, bacteria/fungus, hormones, and—in those less fortunate—decomposition. Dogs follow these scents to find the source that produces them. Scents come off any subject or object in a cone following the prevailing wind, i.e. narrow at the source and expanding outward in a scent cone until it dissipates or is disrupted by barriers like walls or cliffs that cause the odor to swirl and eddy. A dog’s search pattern depends on finding part of the cone and using its nose and training to locate the concentrated source.

Finding the first part of the trail can sometimes take considerable time and patience. There are three main types of scenting methods and most dogs favour one technique:

Air-scenting dogs:

• A heads-up search, often off lead.
• Identify the smell of any human in the area and follow the concentrating scent as the dog gets closer to the target.
• Can cover large areas during the day or night.
• Does not need a track to follow or a specific starting point.

Tracking dogs:

• Nose-down search, usually on lead.
• The dog follows a specific track of disturbance over land.
• Follow the exact track of a specific scent, even if the target doubles back. On a mountain trail a tracking dog would follow the ascending odor trail around every switchback, even if it detected fresher odor blowing down the mountainside.

Trailing dogs:

• A combination of air-scenting and tracking.
• Follows a specific scent.
• On-lead searches, using partially head-up air scenting and head-down tracking techniques.
• Will follow the scent pool off the trail. On the mountain trail mentioned previously, the trailing dog would likely cut across switchbacks if it detected fresher odor blowing down the mountainside.

But how can they follow a scent over hills and through valleys, around rocks and through buildings? Next week we’ll look at the difficulties of tracking scent. These skilled dog and handler partnerships make it look easy, but it’s considerably harder than that!

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There’s still time to win a free copy of LONE WOLF! Our publishing house, Kensington, is very generously giving away 25 copies before LONE WOLF’s November 29th release. For your chance to enter by October 19th, follow the link here: http://bit.ly/2dZYadJ. Not a Goodreads member? Sign-up is easy and free! Good luck!

Photo credit: Cleanboot and Virginia State Parks

Modern Working Dogs

Over the past few blog posts, we’ve talked about the history of working dogs and even the career of one specific WWI hero. Today we’re going to talk about modern working dogs, briefly looking at some of the crucial jobs they do today. Then, in the future, we’ll look at these jobs in more detail.

Military K-9s: Dogs have become a day-to-day part of battalion life for many of the services. They are used for patrol/sentry duty, explosives detection, drug detection, finding fallen soldiers, and signaling enemy approach. They also fulfill an important role as therapy dogs.

Police K-9s: Most modern police dogs are trained for one task such as search-and-rescue, detection of explosives, drugs, arson, or electronics, patrol, and cadaver detection. A very few dogs cross-train; for example search-and-rescue dogs who also do tracking. Detection dogs (drug, arson, electronic, explosives, etc.) are generally trained in just a single odor category, but within this one area, they learn to recognize hundreds of related scents.

Search-and-Rescue (SAR) K-9s: Some of these dogs come from official groups (e.g., law enforcement), but many SAR teams are volunteers who are part of state or national SAR groups. SAR dogs are involved in finding anyone from lost children or hikers, to drowning victims, to victims of natural disasters or terrorist attacks. These dogs include those trained to air scent, as well as dedicated tracking dogs. More on that next week.

Therapy K-9s: Therapy dogs are selected based upon temperament, appearance, and aptitude. Some dogs are trained to be comfort animals for the elderly, the sick, victims of domestic violence, or for stressed-out university students—my own university has dogs brought in for this purpose during exams, and Ann has Kane,  a working therapy dog who visits an AIDS hospice, a domestic violence shelter, and an adult day care facility. Therapy dogs must be tolerant of other animals on-site—other therapy or service animals, pets, etc.—and be willing to endure touches or hugs from total strangers.

Service K-9s: Service dogs are trained to perform specific tasks for their owners and strangers. Cancer detection dogs in medical facilities can detect traces of cancer in patients long before diagnostic tests are accurate. Diabetes or epilepsy dogs are trained to detect low blood sugar levels or impending epileptic seizures so they can alert the owner or a caretaker to get help if the owner is unable to respond. Hearing assist service dogs are trained to alert owners to doorbells and ringing cell phones. PTSD dogs can recognize moments of stress in their owners and can often avert that reaction by their presence and “covering their 6”.

As you can see, these dogs are dedicated, incredibly smart, well-trained animals, who can make life and death decisions and real-time differences for their owners and the public on a daily basis. Next week, we’re going to start looking more at search-and-rescue teams, just like Meg Jennings and her black lab, Hawk, in our upcoming release LONE WOLF.

Speaking of LONE WOLF, our publishing house, Kensington, is very generously giving away 25 copies before LONE WOLF’s November 29th release. For your chance to enter the October 12 – 19th giveaway, follow the link here: http://bit.ly/2dZYadJ. Not a Goodreads member? Sign-up is easy and free! Good luck!

Photo credit: Wikimedia Commons and Ann Vanderlaan

Canine Highlight – World War I’s Sergeant Stubby

We’re starting a new type of post this week: the canine highlight. We’d like to bring to your attention some particularly outstanding working dogs who have shown as much courage as their human counterparts, saved lives, and significantly affected those around them in the most positive of ways. This week, we bring you the amazing tale of Sergeant Stubby.

In last week’s post, we talked about working dogs through the ages.  We mentioned the working dogs of World War I, concentrating on the medical aide dogs that were sent out onto the battlefields after the cessation of fighting to bring supplies to those in need. But there were other dogs as well who joined the cause—and one of those was Sergeant Stubby.

When a young bull or Boston terrier mixed breed dog wandered onto Yale University campus and into the training grounds of the 102nd Regiment, 26th Infantry Division, Corporal John Robert Conroy took a liking to the little mutt. He started feeding the stray and even let him sleep in the barracks. Eventually, Stubby became the Division mascot, spending so much time with the men that he learned all the marching maneuvers, and even was trained by Conroy to salute with his paw.

When the 26th Infantry Division was shipped out to France aboard the SS Minnesota, Conroy smuggled Stubby aboard, and then tried to keep his presence hidden. Eventually, the dog was discovered by the commanding officer. However, Stubby won the officer’s goodwill by saluting him, and was then allowed to stay with the Division openly.

Stubby accompanied the 26th to the Western Front in France, where he proved to be an invaluable part of the unit. After nearly being killed early on by mustard gas, he became adept at stiffing it out early and running up and down the trenches barking at the men to put on their gas masks before going to hide himself. His extremely sensitive hearing was also a boon—he could hear incoming shells long before the men and warned them to take cover, and he could hear the approach of advancing German foot soldiers and warned the sentries of the imminent attack. He was also known to scour the territory of “No Man’s Land” following any fighting, looking for fallen Allied soldiers in need of rescue. Stories of the time reported that he would only respond to the English language, thus avoiding the wounded Germans altogether. His actions in the unit saved countless lives.

During the Meuse-Argonne campaign in 1918, Stubby discovered a German spy in their midst, mapping the Allied trenches to take the intelligence back to the Central Powers forces (Germany, Austria-Hungary, Ottoman Empire and Bulgaria). When the spy tried to make a run for it, Stubby went after him and brought him down, and then clamped his jaws around the man’s rear end until soldiers from his own unit came to take the spy into custody. The unit’s commanding officer was so impressed with his performance that the dog was battlefield promoted to the rank of sergeant. This meant that he actually outranked his owner, Corporal Conroy.

Stubby took part in seventeen battles and four major offensives on the Western Front, and was the recipient of the following medals and devices for his service in battle: 3 Service Stripes, Yankee Division YD Patch, French Medal Battle of Verdun, 1st Annual American Legion Convention Medal, New Haven WW1 Veterans Medal, Republic of France Grande War Medal, St Mihiel Campaign Medal, Purple Heart, Chateau Thierry Campaign Medal, and the 6th Annual American Legion Convention.

Following the war, Stubby went to Georgetown University with Conroy while he studied to become a lawyer. While he was there, Stubby became the mascot of the football team and was infamous for coming out during the halftime break and pushing a football around the field with his nose to the delight of the crowds. He was inducted into the American Legion, marching in all their parades, and even met Presidents Wilson, Coolidge and Harding at the White House.

You can still see Sergeant Stubby today. Following his death in 1926 at approximately ten years of age, he was taxidermied by Conroy and gifted to the Smithsonian in 1956. He is now part of one of their World War I exhibits at the National Museum of American History. His WWI uniform, complete with all his medals, is on display at the Hartford State Armory.

Photo credit: Wikimedia Commons and Smithsonian National Museum of National History