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Walk your dog long enough and chances are you’ll see it: After urinating or defecating, you’ll see your faithful companion kick up a stream of grass and dirt with his hind legs, sometimes in a veritable frenzy, and then trot off.
Some owners find it difficult and take their dog. But the post-poop kick is neither a bad habit to break nor a quirky backyard dance. It is normal behavior and there is a real reason behind it.
They are two signs in one.
Dr. Carlo Siracusa, a veterinary behaviorist at the University of Pennsylvania, says that exaggerated kicking is actually a way for a dog to leave a signal or mark for other dogs. “It’s a form of communication.”
But this marking after urinating isn’t just about claiming territory. It’s also about presence and timing, a way of saying “I was here.” When a dog sniffs where another dog kicked dirt or leaves, he can read the tea leaves (sometimes literal ones) and know how long or recently that other dog passed by. That’s why dogs continue to improve their grades. A scent that is a few days old provides different information than one that was left an hour ago.
The raised mark contains two different pieces of information. There’s the smell and there’s the scratching itself, which Siracusa describes as a visual cue in addition to the smell. Kicking spreads the scent over a wider area of the ground and pushes some of it into the air, leaving a stain that another dog can see.
“If you’re close, you can see me,” he says, speaking from the dog’s perspective. “But those of you who are not here yet will smell that I was here.” He compares it to the way he marks a cat, with a display visible in the moment and a scent that lingers behind.
DOG PAWS THE GRASS AFTER URINATING #Shorts #DogKick #DogVideo
This little ball of fluff marks its territory and leaves messages for other dogs when it kicks its paws back after urinating. Video: DOG PAWS THE GRASS AFTER URINATING, @GhighiVlogs
Courtney Sexton, a postdoctoral researcher at the Virginia-Maryland College of Veterinary Medicine, arrives at the same two-part explanation, although she notes that she has not directly studied ground scratching. Excrement and urine are loaded with information, he says, and kicking helps transmit it.
“If you kick after you leave, the smell will spread over a larger surface and increase the likelihood that someone will [or, more likely, another dog] passing by there is going to catch it.” Some of it floats in the air, so a downwind dog catches it too.
The custom returns to the wolves.
Sexton attributes this behavior to dogs’ wild relatives: wolves. For wolves, territorial issues and scent marking are a pack’s way of indicating that this is its territory and warning others to stay away. Other wolves can read the stress hormones in a mark or find out what the other animal has been eating.
Studies of dogs in the wild show that dogs, like wolves, also leave marks to mark where their territory is. In a 2012 study of a pack of free-ranging dogs, researchers found that the dogs used their markings, including scratching the ground, to establish something like a property boundary and threaten rivals during fights.
A 2024 study of free-ranging dogs found that males were more territorial than females and reacted more strongly to the scent of males from neighboring groups.
Most of the world’s dogs are not house pets, Sexton notes. Many live in freedom and live in dispersed groups where territory still counts. For a dog sleeping in your bed, the stakes are lower, but you stick with your behavior anyway. Even your housebroken pup will often take the same route for walks every day and at the dog park, leaving other dogs’ urine mail among the raised leaves.
For some dogs, it may be nerves.
Siracusa adds a second factor from his clinical work. Anxious dogs, especially in busy environments like crowded cities, may mark as a way of asserting themselves. The point, he says, is to convey a simple “I’m close,” so the dog can avoid difficult encounters with other dogs.
It doesn’t take the idea too far. There’s no data to show that anxious dogs scratch the ground more than calm ones, he says, just a broader pattern he sees in the clinic in which anxious dogs mark more overall.
Scratching the ground is just one way dogs mark. Others include urine marking and overmarking, where one dog deliberately marks on another dog’s scent.
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No one has studied what is really in the aroma.
Dogs also have scent glands in their paws, so scratching will likely release some odor from the paws and spread the initial mark at the same time. But what those glands add to the message has not been studied, according to Siracusa.
“There are glands in the paws,” says Siracusa, but it has not been determined which pheromones they release or what each one means.
However, there is some research on paw odor. A 2020 study found that dogs can distinguish the scent of one dog’s paw glands from that of another, although it was unclear whether they can distinguish the sex of the depositor.
When it is worth paying attention.
For owners, when their precious Lassie kicks up dirt after urinating, it’s usually nothing to worry about. Siracusa says he doesn’t remember any customers finding him worrying or even annoying. Not all dogs do it, and a dog that does it may not always do it.
What’s worth watching is a change from your own dog’s usual pattern. A dog that always scratches and stops suddenly, or one that begins to do so in a forced and uncomfortable manner, could be dealing with the pain, rather than sending a message, especially if it comes with other signs such as whining during elimination.
“I’m more interested in the change in a dog’s normal behavior,” says Siracusa, “than in the individual behavior itself.”
However, for the vast majority of dogs there is nothing to solve. So the next time your dog throws grass and dirt around the yard, let it go. It only matters where you are standing.
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