Why Do Dogs Sniff Butts? – A Simple Explanation

english bulldog puppy from the rear end with reflection on white background

Doggy Got Back

I looove to smell butts, and I can not lie

You other doggies can’t deny

That when a dog walks up to you and greets you in mid-stride

You can’t wait to go around and smell their backside

You get to find out things about the mutt

There’s a lot you can know from sniffing a butt

Butt Sniff 101 – Dogs Sniff Butts to Find Information.

You’re walking with your dog down a trail. You see another person with their dog walking towards you. As you both nod to each other hello, the two dogs pause, sniff one another’s head using indirect eye contact, then circle around each other sniffing the tummy, genitals and under the tail. At this point, either the two of you stand uncomfortable tugging on the leash to move on, or you’re both engaged in a conversation about your dogs, letting them finish meeting each other. 

New York, NY, USA - April 4, 2020: A young dog and an old dog sniff each other in greeting as they walk in the park on a spring day.

So what is going on there? Do they just like smelly butts? Nope. What they are doing is the start of a greeting ritual. Instead of saying hello, shaking hands and asking questions, dogs use body language and scent to get to know one another. What the two dogs were doing was the polite way of meeting for the first time. First meetings are important because it reveals a lot about the other dog, including figuring out their rank. Polite dogs know greeting etiquette. 

So what can they find out about each other? Smelling the anal glands reveal quite a bit of information. The dog can tell the others gender, mental state, physical health, what they ate, if they’ve met before due to their scent memory, their rank, who they interacted with, their age, their mood, what they touched, and reproductive status. 

So how does it work? Dogs have between 150 to  300 million olfactory receptors compared to 5 to 6 million in humans, depending on which Vet you ask. Dogs have another scent system called the Jacobson’s Organ System in their nasal cavity, which has two sacs filled with fluid that allows them to smell and taste at the same time.

Saarloos wolfdog young female getting to know other female dog.
Sniff Sniff, she’s had a hot dog!

Hey man, that’s not cool, don’t sniff my butt! I know it can seem alarming when a dog comes up to you and sticks his nose where you think it shouldn’t be, but he’s really not doing it to be gross, or creepy. He’s just curious about you and wants to get to know you better. No need to get embarrassed about it. Some people find it offensive, but to a dog, it’s a polite ritual. Dogs sniff butts to find information.