Keep Your Pet Healthy in 2020 Keep Your Pet Healthy in 2020


How Dogs Breathe and Detect Scents at the Same Time

Analysis by Dr. Karen Shaw Becker

scent tracking dogs

Story at-a-glance -

  • It seems the sky’s the limit when it comes to the amazingly talented and skilled canine nose, including helping researchers in Alaska locate bat habitats
  • Your dog’s sense of smell is thousands of times better than yours — he has about 50 smell receptors, while you have just one
  • One secret to a dog’s sniffer: while humans use the same air passage to both breathe and smell, dogs’ noses are able to separate those functions

Recently, I came across a fascinating article in the Juneau Empire, an online publication in Alaska, about how dogs are using their absolutely amazing sense of smell to help local bat researchers:

"To expand our understanding of the habitats used by hibernating bats, ADFG [Alaska Department of Fish and Game] bat biologists and volunteer citizen scientists do road surveys, listening for bat vocalizations with special bat detectors.

These surveys are primarily focused on finding areas of concentrated bat activity at the seasons of entry to (and emergence from) hibernation. Then foot surveys in those areas look for the right kind of habitat; bat detectors are used to see if bats are really at that site and identify the species of bat.

If all that points to the presence of bats, trained bat-scent-detecting dogs are brought in, particularly during the time of beginning hibernation (the so-called swarming period), to sniff out the exact crevice housing the bats. When a search dog signals that it has detected the scent of bats at a particular crevice, researchers may look for the distinctive feces of bats in the crevice.

So far, the scent-detecting dog searches show great promise for locating hibernacula (although not in the rain), and the method should be tested elsewhere, in other habitats and climates.

In the meantime, the method will be used here to locate more hibernacula and develop a clear picture of the habitat needs of the bats. That's critical information for land managers — and a great application of an ancient hunting partnership between humans and canines."1

It seems every day we learn of some new and invaluable application for the remarkable canine sense of smell!

Why Your Dog's Adorable Wet Nose is Also a Scientific Wonder

The human nose contains about 6 million olfactory receptors that allow us to recognize thousands of different smells.2 It sounds like a lot, until you realize that inside your dog's nose there are up to 300 million such receptors.

Humans can detect certain odors in parts per billion, but dogs detect them in parts per trillion. Plus, your dog has a part of her brain devoted to analyzing smells that's about 40 times larger, proportionally, than the same area in your brain.3

This explains why a dog's sense of smell is anywhere from 10,000 to 100,000 times more acute than your own, and also why the canine nose can be described as nothing short of amazing. According to NOVA:

" … in her book Inside of a Dog, Alexandra Horowitz, a dog-cognition researcher at Barnard College, writes that while we might notice if our coffee has had a teaspoon of sugar added to it, a dog could detect a teaspoon of sugar in a million gallons of water, or two Olympic-sized pools worth.

Another dog scientist likened their ability to catching a whiff of one rotten apple in two million barrels."4

Get my top tips for choosing the best pet food hereGet my top tips for choosing the best pet food here

9 Fascinating Facts About Dog Noses

1. Dog vs. human sense of smell: no contest — Scientists estimate that our canine companions' stellar sniffing abilities range anywhere from 10,000 to 100,000 times greater than ours. Whereas you have one olfactory receptor, your furry BFF has about 50.

2. Short-nosed dogs have a less acute sense of smell than their longer-nosed friends — Short-nosed and flat-faced dogs such as the Pug, Pekinese and Boxer, have fewer scent-detecting receptor cells than dogs with longer snouts, such as a German Shepherd or Bloodhound, which have 225 million and 300 million, respectively.

3. The canine nose is specially designed for scent detection — When humans inhale, we use the same air passage to both breathe and smell. Dogs' noses, on the other hand, include a fold of tissue that separates the two functions. Both human and dog noses contain bony turbinates, or plates, but inside a dog's nose is a microscopically small, spongy membrane containing the scent cells.

Like an accordion, if you could flatten all the folds in that membrane, the total surface may be as large as 60 square inches.5

4. When it comes to picking up scents, floppy-eared dogs have an advantage — Many dog breeds feature long, floppy ears to give them the unique talent of fanning aromas up into their nostrils, making their noses all the better to smell with.

5. Scent-tracking canines are selective sniffers — Some dogs are enthusiastic about every one of the thousand things they catch a whiff of, say, on a walk in the woods or romp on the beach. But scent-tracking dogs zero in on specific targets and can walk right past a squirrel to find the source of the scent they're focused on.

6. Breeds with the most talented noses — Bloodhounds have such scent-sensitive snoots that their excellent detection skills are helpful for purposes of law enforcement. They've even carried weight in court. Beagles are often chosen for sniffing duty by narcotics and U.S. Customs and Border Patrol (CBP) agents.

German Shepherds work with the police and military in human rescue operations and also drug detection. Dachshunds were bred to sniff out badgers, and the Harrier was used to hunt rabbits (aka "hare"). Other notable noses belong to Basset Hounds, several Coonhound breeds and Labrador Retrievers.

7. Some dogs trail, others track, and some do both — There's a difference between dogs who can trail, and others known for their tracking abilities, but many dogs are trained to do both, as one article describes:

"These dogs basically follow footsteps, they are orientated to a mixture of human scent and ground disturbance. They work on a long line and do not work from a scent article. They follow the freshest track.

(Trailing dogs) usually work from a scent article. They can work on or near the track to a good distance from the track depending on wind and environmental conditions, but they follow only the specified scent. They work on a long line and can work in wilderness, urban areas, buildings, in vegetation or on hard surfaces, (pavement)."6

8. What's that wet nose all about? — Dogs have wet noses for a variety of reasons, the most important of which is that a damp nose picks up smells better. Dogs also lick their noses quite often to clean them, and a wet nose helps cool down their bodies, as well.

In case you've been told that if your dog's nose is warm or dry, it means he's sick. That's a myth! A warm dry nose by itself doesn't mean your pet has a fever or is sick. Dog (and cat) noses go from moist and cool to warm and dry and back again quite easily, and it's perfectly normal and healthy.

9. Canine nose prints are completely unique — Like the fingerprints of humans, a dog's nose print may be just as individualized. There are companies that register the nose prints of canines and store them in case the pet is lost or stolen, and kennels have begun a similar procedure. Canada has used this procedure to identify dogs for decades.7

If you're interested, you can make your own dog's nose print using food coloring (never paint or ink). First, wipe her nose with a towel to dry it, pour the food coloring over a folded paper towel and gently press her nose onto the ink, making sure to cover the impressions on the sides. It may take a couple of tries! Food coloring is safe for this purpose and comes off easily. Dry the paper towel and store it away in case it's ever needed.