Dog marking behaviors use smell communication and leg lifting to spray urine and mark territory. Although they primarily use urine, some pups also scratch the ground after eliminating to leave visual signs while the paw pads leave scent cues. The timing of leg lifting behavior coincides with puppy developmental stages but varies from puppy to puppy, with some starting much earlier than others. A puppy's leg lifting also can be influenced by spay and neuter surgeries, although both intact and "fixed" pets use urine to mark. This behavior is very different than potty accidents.
Why Dogs Mark With Urine
Marking with scent not only indicate ownership but also act as a canine bulletin board. You could call it doggy Pee-Mail. Body language and vocal signals require the pup to be present to get the message across. But scent communication left by urine tells other dogs who has been there before them, how long ago the mark was left, the sexual status of that dog, and other important information.
The scent of urine tends to fade as soon as it contacts the air. That’s why dogs constantly freshen with new markings on top or nearby the original. Some pups become so enthusiastic, they seem intent on throwing their hip out of joint to "baptize" everything they can reach!
Both male and female dogs urine mark—boys start between six to twelve months of age—but typically it is the male that is most enthusiastic. And, it is the intact dog able to produce puppies that exhibit the most prominent behavior. Females may leg-cock to announce their breeding availability to male dogs.
Dog Marking vs Puppy Potty Training
Marking is different than elimination behavior. When the purpose is to simply void a full bladder, female dogs usually urinate downward in a crouched position over a flat surface like the ground. Male dogs also often squat to urinate. All puppies squat to urinate and the urge to actually mark develops with maturity from about five months on, depending on the individual pup.
In contrast, marking is done from a standing position by cocking a rear leg and aiming the urine stream at a (usually) vertical object. This places the scent at a convenient nose sniffing level, just as people would place a Post-It Note at eye level to attract the most attention.
It takes very little urine to send the intended Pee-Mail message. During walks with your pup, he may stop you every five yards or so to leg-cock against a tuft of grass, telephone pole, or other obvious landmarks. By the end of the walk, he may run out of urine but continue to leg-cock, in effect simply going through the motions. Just the pose can be a visual signal to any watching dogs.
However, they sometimes get carried away and mark inappropriate targets. Extremely dominant dogs may even urinate against a person's leg, and intact indoor dogs often feel compelled to scent their household top to bottom. Neutering and spaying greatly reduce the leg-cocking behavior, curtailing the baptism of bedroom walls, tires, and furniture.