Q. Perdie is my short coat Chihuahua.  After he turned one year old, he began marking (peeing to mark his territory) in the house.  We had him neutered at six months old.  It started again after I had a friend bring over her two dogs.  Perdie is fully housed-trained and still does all his business outside as usual.  How do I get him to stop?

A. Surprisingly, it is not only males that mark, some females try to mark too.  Once a dog is neutered and or spayed the behaviour usually does not show up at all. Dogs that are not neutered or not spayed will definitely mark.  Males will mark to attract a female and to tell the world that the area belongs to him.  It is hard to train a male not to mark when all the hormones are involved.

Most likely Perdie’s urination is motivated by the visiting dogs. The uncanny onset of the behaviour post dog visit at his age and after one year of perfection is the tipoff.  But, although the motivation for urine-marking is not identical to that in straight house-training, for example: emptying of bladder versus some olfactory or social trigger, the behaviour is the same: the dog is depositing urine in undesired locations.  The dog in question has the requisite spinal cord and so can be conditioned to deposit urine only in desired locations-outside.

For two or three weeks, treat him as you would an untrained puppy.  In fact, you must put him in a safety zone area when you aren’t spending time with him.  Many puppies, once they have performed both functions outside, can be trusted for a certain amount of time inside, say half and hour.  In Perdie’s case there is no safe zone.  This is the one deviation from a standard house-training procedure.  Also, clean all the places where he has urinated with an enzymatic, urine-neutralizing cleaner.  Or if you can do so safely, use some bleach with soap and water to clean the area.

He should be supervised in the home just like he was when he was a pup.  This is not the “I’m watching TV or on the Computer Supervising the dog” kind, but the “eyes on dog all the time” kind.  It really helps the house-training to have a two or three week period where the dog is prevented, through diligent management and frequent enough outings, from making even one mistake. When he urinates outside where you want him to, reinforce him with praise and preferably a small food treat.  It must be completely unambiguous that he has done a glorious thing.  In order to do this in a timely manner, you have to accompany him outside for a while.  If he pees, then comes in and then is rewarded, it is too late.  The food must hit his mouth within a second or two of his completing his pee.

When this regime has been in place for a few weeks, start loosening up the management when indoors.  Stretch him for longer periods with eyes on him.  If you see him wind up to mark, interrupt him quickly and hustle him outside.  Praise as usual.  Sometimes the first two parts of the regime-the management and habit forming work like a charm and so no interrupts are necessary.  But often well timed interruptions are vital, so it’s really important to be vigilant in this phase.  If he succeeds in sneaking one or more in, it is a sign you need to be more vigilant.

Most dogs, after a few interruptions, stop trying.  Once you’ve had some weeks of vigilance but no attempts, you can start to slack off.

This procedure can drag on if there are compliance holes.  If you kinda sorta do it, it often won’t work at all.  Sloppy confinement, no reinforcement for correct behaviour(the old “he knows, he doesn’t need to be rewarded blah blah ” trap) or missing the first attempts in the interrupt phase can each derail the outcome.  All bad habits can be broken but you must be firm and consistent.