I was looking through some things and found this interesting, but I don't know if this applies to your situation or not. :)
If your yorkie does fine when you are not at home, then it doesn't seem like a problem to me, but what do I know? I have loved my doggies no end. :p
Anxiety
Many dogs become over attached to one or all of the members of a household and become extremely anxious when they are left alone. This can result in quite extensive damage which is usually found around the door that the person leaves through and any escape route the dog may discover such as cat flaps, open windows and gates. These dogs usually become hysterical on their owner’s return and take several minutes to calm down. The behavior only occurs when the dog is separated from the household members to whom they are attached. In some cases, dogs that can cope when left in the home will become destructive when left alone in a strange environment. Dogs that are destructive because of anxiety tend to follow the people they are attached to around from room to room and try to maintain physical contact or eye contact as often as possible. Often barking, howling, toilet training problems and, in extreme cases, self-mutilation accompany this type of behavior.
There are many different reasons for anxiety in dogs which can result in destructive behavior. This can range from the hormonal swings caused by seasons in female dogs, to insecurity in elderly dogs. The most common type of anxiety is cause by over attachment to owners.
It is very flattering for some owners to have a dog that worships them and adores them. Unfortunately, this sort of dog finds it distressing to be parted from the object of his adoration. To resolve the problems with a dog like this, it is important that the owner is able to cool their relationship with the dog whilst building the dog’s confidence when being left alone.
Things you can do to make your dog more independent and less anxious when left alone
He will need to be left alone for short periods in the house whilst you are out. Until he can happily stay in one room while you are in another part of the house, there is no point in trying to get him used to being left alone while you are away. Get him used to being in one room, or perhaps acclimatise him to an indoor kennel, covering it with a blanket to make it a den type area.
He must be discouraged from following you from room to room and making constant physical contact. You should be aware of this and close doors between yourself and your dog. In addition, you should be firm with him and encourage him to sleep in his bed and not be constantly underfoot.
Other household members and friends should be enlisted to assist by taking him out for walks, playing and feeding him. This will avoid him becoming dependant on one individual or certain people in the household.
When he is left, the light should be turned off, a radio should be playing softly and items of the owners clothing can be left in his bed and on the other side of the door. This will also help create a restful environment which still sounds and smells reassuring to him.
You should ignore him completely for 20 minutes before leaving him and for 20 minutes upon your return. The dog should only be greeted when he has calmed down.
A special chew or toy can be left for him during your absence although this should be removed on your return. Also ensure he is well exercised at least half an hour before leaving him.
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