Can Dogs Smell Underwater?

We've talked about how powerful your dog's nose is before, and even if we hadn't, you probably already know (it's so obvious in the way they sprint down the hall every time you even think about cooking a meal or opening a treat bag). But how powerful is your dog's nose really? Do they have a super-hero style nose that can sniff out a scent in the most difficult of locations - like, underwater for example?

What do you think - can dogs smell underwater? 

They can! In fact, some dogs are specially-trained to smell underwater to locate people, drugs, and other things underwater. Every year, dozens of search-dogs are trained to sniff out things that could be sitting at the bottom of a lake, stream, river, or other body of water. Often called cadaver dogs - a grim name, but a fitting one, nonetheless - these animals are trained to sniff out things or people that may be under the water's surface. 

So, do you think your dog can sniff out a scent that's coming from under the water? If you're not sure, we've laid out a few signs that you should look out for. If these things are happening near a shoreline, by the lake, near a river, or close to any body of water, it's possible that your dog is picking up a scent. Check out the rest of our guide to get a better idea of how you can tell when your dog is picking up a scent, how to train your dog to smell underwater, and a better, clearer picture of just how powerful your dog's nose is. 

We'll get into the specifics of doggo smelling in the next few bits of our article (skip ahead to the science behind your doggo's nose section if you're too antsy to wait for that part), but it should be pretty apparent that your dog's sense of smell is second-to-none. 

What's exceptionally cool about your dog's sense of smell is that they're well equipped to smell underwater. Not only does your dog have the ability to smell much stronger, but they're fitted with two holes in their skull that naturally draw in scent without inhaling - meaning, if they dive underwater and open their mouths, they're able to bring in that scent without inhaling water, leading them toward the scent's originating point. 

If you think your dog is picking up a scent from underwater, you'll likely notice some strange behavior happening on or near the water. First, your dog might make some adjustments or twitching motions with their head to get a better handle on the scent. Then, they'll probably get to sniffing - we don't mean they'll sniff the air a time or two and then move on, instead, they'll probably get super obsessive about the smell. 

You may find them running around the water's edge or the length of your boat with their nose high in the air. Then, your dog will likely bark a ton, growl a bit, or do whatever it takes to get your attention on the water so that you know what they know. Don't ignore your dog! Hear your pup out, see if you can pick up on anything funky, and if you're exceptionally curious - and its safe - take a dive down to see if your dog is picking up something. 

Dogs who have been specially trained to sniff out specific scents in the water are often called cadaver dogs, and they've been helping law enforcement for decades. In fact, training of cadaver dogs began in the 1970s, and the first police dog in the United States that helped with cadaver search - a Yellow Lab named Pearl - started her career in 1974.

People figured out that the scents of bodies and other objects released into the water currents, which then are released into the air. Dogs, with their powerful noses, can track the scent to the most powerful point - where the smell originates. There are hundreds of dogs every year who are specially-trained to seek out objects or people that are submerged below the water's surface.

Your dog's nose is designed for a smelling ability that far surpasses that of human capability - in fact, smell (or olfaction, as it's called) is a dog's primary sense. Dogs actually trust their sense of smell over any other sense, and can you blame them? 

Dogs have about 220 million olfactory receptors on their noses. To put that in perspective, humans have about 5 million. More than that, each of their olfactory cells has way more cilia - tiny hairs - than humans (about 100- 150 on each cell, while humans have about 6-8). Dogs noses are so finely-tuned they can even smell underwater thanks to the vomeronasal organ - commonly called the Jacobs organ. 

This organ runs along the bottom of their nose and connects directly to the olfactory lobe with about 600 nerve bundles. In addition, a dog's skull contains two, tiny holes in the roof of their mouths that allow them to pull in a scent without inhaling, letting them draw in a smell while they're diving through a water.

The wonderful thing about dogs is that they're exceptionally gifted in many departments humans aren't and they're - usually - ready and able to share their talents with their humans. If you notice that your dog has an exceptional gift for smelling, especially for dog standards, you should look into getting your dog specially trained to help sniff things out under the water. 

As we discussed earlier, cadaver dogs have been used since the 70s to locate people and objects that might be deep under the water. Of course, these dogs go through rigorous training to do this. You might not be able to do this at home, but you should look into programs that could train your dog to do this. This is far more complicated than your basic sit, stay, and reward with a treat - in fact, it requires some pretty gross technique.

For example, dogs need real-life-situational training if they're planning to locate people in the water, but obviously, trainers are not able or allowed to use humans or human remains in the water. Instead, they use pig remains. Because of the nature of the work, remains at different stages of decomposition are vital to a dog's training, so pig remains - described as an ever-changing scent - do the trick nicely. 

First, trainers will hide the pig flesh on land - behind bushes, trees, etc. Then, gradually, they'll move them closer to the water, then a few centimeters into the water. This gets the dogs accustomed to the changing scent. 

As the scent rises in a gaseous state to the surface, the dog is able to pick up the scent. Then, dogs will hop on a boat with their trainers. Eventually, they'll be so well-trained that when they pick up a scent, they will become lively, running from one side of the boat to the other. They even teach dogs to directly look handlers in their eyes and bark to signify they're smelling something off.