I have a one year old Yorkie & yesterday I rescued a one & a half year old Bichon Frise. They get along so good & they've become inseperable within a day but my Yorkie will not stop humping the Bichon. I'm worried that it's a territorial thing because I brought a new dog into the house. Shed some light on this please?
They're both neutered.
It is a territorial thing. Your Yorkie is humping the Bichon Frise in a display of dominance. By doing this, the Yorkie is telling the new dog that the Yorkie is King of this castle. In every family there is a pecking order, and your Yorkie is merely showing the new comer that Yorkie is higher up in the family pack than the new comer is. In time this will (usually) wear off.
Tags: Yorkie

Get the dog fixed.
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It's more of a dominance thing. Your Yorkie is showing the Bichon that he or she is the top dog. If they're both neutered or spayed, that might help somewhat. Dominant dogs will often mount subordinate dogs to show dominance, regardless of gender.
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That is an especially annoying dominance behavior. Are both dogs neutered? This will be a step towards fixing the problem, but it is not a complete step. Try to be neutral, calm, patient – and interrupt the behavior every time. Take the Yorkie off the other dog. It's very important that you do not scold or become upset – just neutrally interrupt the behavior.
If this were my dog he'd get 2 strikes and then he's in a time out. Only you know the temperament of your dog and whether this would be too much of a punishment for him. But, I believe that there need to be consequences for this obnoxiousness and I personally would escort that dog to his crate or empty room after I have interrupted him once.
Teaching an alternate behavior would be good. Take your dogs to a training class and learn about how dogs learn – you'll be very happy that you did, and so will your dogs!
http://www.ccpdt.org/rstr/index.html
to find a trainer
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It is territorial. You don't mention if they are same sex or neutered. You can make a noise at the instant this is about to happen or you can consult the "Dog Whisperer" web site for the perfect answer.
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It is a territorial thing. Your Yorkie is humping the Bichon Frise in a display of dominance. By doing this, the Yorkie is telling the new dog that the Yorkie is King of this castle. In every family there is a pecking order, and your Yorkie is merely showing the new comer that Yorkie is higher up in the family pack than the new comer is. In time this will (usually) wear off.
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Certificate II and III Animal Studies