dog becoming possessive/protective of one owner

[Giselle]

Okay, here's an honest question, and I'm not trying to sound pedantic or anything, but why on earth did your girlfriend continue to lean over after the dog had already growled??? I can understand why you're concerned, but try to see it from the dog's point of view. He's obviously uncomfortable with somebody leaning over him. He growls to warn that person. The warning is not heeded. Of course, he's going to bite.

First things first: Many dogs (even the most submissive ones) do not enjoy being leaned over, *especially* new dogs. New dogs HATE being leaned over. They're already trying to adjust to a new situation. Being leaned over just adds a whole 'nother element of stress. So, for now, avoid leaning over or doing other threatening movements towards him (i.e. grab of the head/neck).

As well, right now would be an excellent time to initiate NILIF, or Nothing in Life is Free: http://k9deb.com/nilif.htm

So now you know what you have to do. But if you do ever find yourself in this situation again, teach the dog "Off". If he growls, tell him to get off the furniture. Do NOT grab his neck/collar. If you must physically remove him, clip a leash onto him. In my house, new dogs do not get furniture privileges until they've learned the command "Off". This stops any unnecessary guarding.

[vader24]

Okay, here's an honest question, and I'm not trying to sound pedantic or anything, but why on earth did your girlfriend continue to lean over after the dog had already growled???

this was my fault. He will make growling noises sometimes when I play wrestle with him, so I assumed he wasn't seriously growling and told her to try again...very stupid, I know. I've stopped the wresting/rough play with him, so as not to encourage aggressive behavior.

As I've said, he's a really, really friendly dog even with strangers so it was very surprising. But I agree, I should have told her to back off. I've been trying the NILIF approach for a few days now, thanks for the info. We adopted this dog from a shelter (he's 6 yo) and he was somewhat trained, so it's easy to get him to sit, stay, etc. and he's already picking up on the new rules. He was actually trained not to jump on furniture, this was a bad habit we encouraged, but he now knows that he can't jump up until we pat the couch to invite him, and he always gets down immediately.

I think my main concern is that he's somewhat obsessive with me still - always staring at me and not paying attention to my gf. I don't think he's challenging me - if I make eye contact he'll look away, I guess he's just looking for me to give him attention. But I want him to see my gf as my equal, and thus have an alpha role to him too. We are going to try to get the two of them to bond via walking, feeding etc. I'll update on any progress.

[Karen]

Oh, good - glad to hear some progress is being made, I hope it continues. Thanks for keeping us updated, and good luck!