Canine Scent Marking: Who's Peeing Where—and Why?

Tracy Libby
Canine MarkingIs there a meaning when your
dog lifts his leg?

It's jokingly referred to as pee mail, but canine urine marking is serious business for dogs. Sure, most of us go online daily to check our e-mails, but did you know dogs have a similar modus operandi? It’s a protocol that pre-dates electronic gadgetry by hundreds, if not thousands, of years. Dogs don't need wifi, but "pee mail" is a highly complex and frequently misunderstood method of canine communication.

No doubt you've experienced some sort of scent marking behavior with your own dog. But do you know why he sniffs other dogs' urine? Or what tidbits of information he's finding when he sniffs where other dogs have peed?

Dogs use urine to mark territory—to leave a message, so to speak. Then other dogs come along and check the message and may leave a message of their own by marking over or adjacent to the original spot. There's a lot of interesting information in these messages, and by checking "pee mail," a dog can determine the gender of the dogs who came before him and whether they are spayed or neutered. He can also tell if there's a female in heat or coming into heat, as well as determine the health, stress level, and social status of the dogs who have previously marked the spot.

Until recently little research has been done on scent marking, and much of what we thought we knew was based on empirical or anecdotal information and general observations. For example, many owners thought only male dogs marked and marking was all about status-related behavior. However, according to a 2011 study by scientists Anneke Lisberg and Charles Snowdon, both male and female dogs mark—but they do it in slightly different ways, and possibly for slightly different reasons. Dr. Lisberg observed and recorded dogs sniffing and urinating at the entrance to a popular park—documenting who urinated when and where, and which dogs participated in bum sniffing (scientifically known as anogenital investigation). In brief, here's what she found:

  • Males and females were equally likely to urinate immediately upon entering the park, but males often urinated more frequently than females.
  • Intact males with high social order are most likely to over-mark (pee over another dog's scent).
  • Females spend a lot of time investigating the urine of unfamiliar male and female dogs; while males are primarily interested in what other male dogs peed on.

Surprisingly, she notes that females never over-marked, but rather "adjacent marked" or urinated nearby, as opposed to on top of the urine mark left by another dog.

I find this interesting because my five-year-old, spayed, female Australian Shepherd literally waits for my male dogs to urinate and then goes over and urinates on top of it. Most days she stands right behind the boys and can hardly wait for them to finish their business so she can mark on top of it. If they don't move fast enough, she's likely to piddle on top of them. She also possesses an uncanny acrobatic ability to stand on her front feet and hike her rear feet straight up a tree, bush or fence to urinate as high—if not higher than my leg-hiking males.

What does all this mean? I'm not sure. But I'm thankful the only marking that goes on at my house is outdoors, as it's not uncommon for dogs to mark indoors, outdoors, or both.

What's An Owner To Do?

There's still a lot we don't understand about canine marking. For instance, what is the distinction between over-marking and adjacent marking? Do they have different functions? Why do some dogs mark while others do not? What does it tell us about the dogs, their personalities, temperaments, and social status? Data also indicates that marking may be a strategy dogs use to avoid conflict. What does this say about dogs who are forced to greet other dogs on leash without the ability to urine mark?

What experts do know is that urine marking is a natural canine behavior. Research indicates it develops after sexual maturity, with 70 percent of urine marking dogs starting by 1 1/2 years of age, and 90 percent before 2 years old. If your dog's marking has become an issue—especially indoors—consider seeking the expertise of a knowledgeable dog trainer or behaviorist to determine what circumstances elicit the behavior and possibly counter-conditioning strategies, such as spaying or neutering.

Equally important, a veterinary check up may be necessary, as some medical conditions, such as cystitis, kidney dysfunction, endocrine abnormalities, incontinence, house-soiling, and geriatric onset can inadvertently be mistaken for marking.

Consider also keeping a log of your dog's marking behavior. Yes, it sounds eccentric but observing dogs in their natural habitat—also known as ethological studies—is the ole-fashioned way that many experts still study animals. It may provide valuable insight should you decide to seek professional help. If nothing else, you may learn a thing or two about your dog's behaviors.

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