Thank you! The 'pack' thing definitely makes sense, and his behavior does seem like he's just trying to be dominant and protect us. It looks like you're right - I'll have to 'show him whose boss!' Are there any ways to let him know specifically that growling and baring his teeth isn't something we'd like him to do? For example, when training my cat to not do something, we would spray her with a spray bottle every time she did the think we were attempting to keep her from doing. What can I do with Buck when he growls or bares his teeth to get the same effect? Would just saying something like, "No, Buck!" in a stern voice be enough? Or would I have to implement some sort of punishment into it? I just want to make sure that all of my bases are covered