We haven't had any major behavorial problems with Duke outside the norm of being a hyper puppy/normal biting/etc, but lately he's started being aggressive about certain things, usually food. If he has a bone or treat and we try to go near him, he growls at us and gets very tense (assuming we'll take it, I guess). Today he was on my lap and my boyfriend came up and he was growling for some unknown reason, and when my boyfriend got closer he bit him in the face. This is the first time he's ever bit someone aggressively. What do we do to stop the growling/protection of things?
Welcome to the forum I would say that the biting is a combination of confidence, play, wanting to keep what he has (whether that's food or a nice comfy spot on your lap) and thinking you might take it away. The solution is to teach him that he does not have to worry that you'll ever take food away and does not have to worry if anyone approaches you while he's sitting with you. A critical part of teaching him that he doesn't have to worry about his food being taken away is.....never taking his food away Leave him in peace when he is eating or else stand at a distance and toss more food (eg kibble or meat) to him. Your appearance should only mean he gets more, never less. You can do the same kind of thing when he's sitting with you - have your boyfriend toss him treats so that his approach means something nice.
Thanks! He's fine with his actual food bowl, it's just his bones he's been getting protective over.. and we also brought home a bag of unopened dog food today and he stood by it guarding it and growling it haha. Just wondering how we should address his behavior when he's acting like that? Also how to deal with situations like when he just bit my boyfriend (it was a mean bite, not a play bite. He definitely shouldn't have got that close to his face, he just really wasn't expecting he'd bite him as he's never done that before)? We put him in his crate as soon as we could get him there (he was biting/growling at us as we tried to put him in)
Sometimes prevention is the easiest road to take. I would say don't give him bones that he can't eat up completely in about 10 minutes and don't leave food where he can sit by it and growl over it. Also, make sure your boyfriend doesn't suddenly put his face close to your puppy. And you could maybe teach your pup to stay on the floor for now, rather than sitting on your lap - have a look at this article which you might find helpful: http://www.thelabradorsite.com/training-your-labrador-not-to-touch-or-climb-on-things/
Here's another excellent article about resource guarding that might help: http://www.thelabradorsite.com/how-to-stop-your-dog-growling-over-food/