Welcome to our weekly 'Ask a Vet from the SF SPCA' feature on 7x7.com. Dr.Jeannine Berger, DVM, DACVB is a board certified veterinary behaviorist who counsels guardians whose pets’ issues are beyond the scope of training. Think of her as a pet shrink…at your service. Ask your own questions in the comments!

Q: My dog loves to run off leash when we are at the beach or the park. At the beach, she always manages to find some kind of smelly mess to roll in. At the park, she finds some stinky spot in the grass and covers herself in stench. Why does she do that?

A: This question brings some really smelly memories for me. We used to have a German wired-haired pointer named Birka, growing up in Switzerland. Every Spring after the snow melted, the farmers would spray the liquid cow dung on the grass for fertilizing. This was Birka's favorite time and although we tried really hard to avoid those freshly dunged fields like the plague, she always seemed to know exactly where to find those stinky spots. It sounds just like your dog, and I feel for you.

To my knowledge, rolling behavior has not been studied in the domesticated dogs, however, a few studies describe the behavior in wolves or other wild canine species. There is no doubt that oflactory communication plays a role in this type of behavior. Whether it is an old evolutionary behavior or our domesticated dogs just savoring the flavor of stinky smells, we don't know for a fact.

The question remains: Seeing that dogs can smell olfactants, wouldn't that mean the horrible smell would be atrocious to carry around on your own coat? It makes me believe that one of several facts must be true:

1. They must like the smell
2. The smell makes them more attractive to other dogs
3. The fact that your dog found something really stinky needs to be broadcasted to all his doggy friends at the beach or park.
4. Or maybe it is about leaving your dog's scent on the found item: "Here, I'm marking it with my smell – it's mine now."

No matter what the real reason is, look at it as a form of canine communication–one I think we humans will never fully appreciate.