You have a male husky mix, this dog cannot help but act on instinct. He NEEDS to show any dog that arrives in his territory that he is already resident and pretty happy to stay where he is. An entire female is an asset as far as your dog is concerned and he is proving that it is worth sticking around and having puppies with him. The only way he has to do this is to prove that he defends his territory with no violence, his pee says enough about him to deter other males (or at least that is what he is demonstrating). The fact that he can't mate does not reduce this instinct in most husky crosses unless they have very very very strong leadership and work to do. A dog like this exposed to entire females can not be blamed for his actions. Get active, learn how to get respect from the dog so he is not in the position that he feels he should mark and until you have control do not allow entire females on your property. Basic rule is that your dog should not see your house as his, but should defend it for you.