Dog on dog aggression

I have a male lab mix that is almost two years old. I got him when he was three months and he was already neutered. It is likely that part of his mix is with pit bull as most of the other dogs at the shelter I got him at were. He has a problem with spontaneous bouts of aggression towards other dogs. Let me start by saying he seems to love other dogs he gets incredibly excited to play with any other dog. Whines if he is somewhere where he can see another dog and not play with them, never barks or growls as he is approaching other dogs on leash etc. He usually plays for awhile doing normal acceptable behavior chase some light wrestling etc. Eventually however he'll become interested in toys, which I have now completely taken away because they cause problems. This play usually takes place outside though so he will find literally any object a stick, a piece of bark, clump of grass, you name it and he'll treat it as a desirable object. Then the problems start if he ever relinquishes this object and the other dog even trots over to smell it he comes barreling back growling and getting aggressive wrestling bitting. If hes holding onto the object and the other dog finds his own or even seems to be poking around in the dirt or by the fence at something that could be a similar object same story. Sometime when hes been playing for a while with dogs and they are all tired and just lying around he will go get an object and just plop it down within distance of the other dogs and lay down slightly removed from it and wait for one of the dogs to even come in the direction of it and same story aggression. The behavior is particularly frustrating because he seems to be obsessed with other dogs and want to play with them so badly and does for a while but will eventually exhibit this behavior. He is never aggressive towards humans beyond the normal someones at the door bark/growl until I see who it is even if its someone I don't know and hes happy. I can feed him and approach and pet him as he eat etc. I will say that this behavior normally takes place in his own yard which makes it slightly more understandable but still unacceptable. He still does similar things when we go to public dog parks though. Many of the dogs that come to play hes known for over a year now is still ecstatic to see them but eventually gets aggressive. Most of what I've read seems to say that this is an instinctive behavior and there is little you can do and merely suggest for this particular dog no toys or objects which is essentially impossible in a big backyard or just not letting him interact with other dogs. I don't like this solution for many reason and was hoping for some advice on how to curb this behavior what to do when he does do this etc. Thanks in advance sorry for the long post.

This is more resource gaurding, and rude behavior. Dog aggressive dogs are always aggressive to other dogs, and at best have to be trained to accept one dog at a time.

I would work on teaching a SOLID Leave it and recall. This way you can verbaly get him to leave the object he is intending to gaurd and/or call him to come to you to deter him chasing down the other dog.

There's nothing rude about it. It's a very natural behavior, based on survival instincts.

For the OP, since he'll play for a while before starting to guard, I suspect he's either overstimulated or tired. I wouldn't necessarily stop letting him play with other dogs, but I would watch for indications that he's had enough and remove him before then. Sometimes when they start playing with things like clumps of grass it's a stress sign, but not always and without seeing it, I can't say for sure.

Also, FYI, it's easier to read a long post if you can break it up into short paragraphs.

Corgipower has great advice about giving him breaks. Very true. I personally don't wait for stress signs. In a high stress environment like that, I enforce a 10 minute relaxation/water break every 30 to 45 minutes.

Tsume'sMom is right that he's resource guarding. What I usually do is when the dog first shows the signs of aggression towards the other dogs, I take the object away whilst giving it a firm "No". Dogs seem to lean very quickly that if they can't share, they don't get to play with it either.

I agree that teaching "leave it" is definitely helpful. You can do the above in the meantime or in combination. I've had great results with both.

So, your dog has an object, another dog comes along and your dog tells that dog to go away because your dog is afraid that dog will take his item away.... so instead, YOU take his item away. This doesn't help the situation, if anything it'll make it worse.

I definately agree with CP, do short play sessions and try to end them before your dog starts to guard. If you are not able to do that, another thing I have done is to distract the other dogs when your dog has an object, so that your dog gets completely ignored. Often when that dog sees that none of the other dogs care that he has something cool, it will lower the value of the item he's guarding and he may stop guarding.

I'm going to have to respectfully disagree. I worked for a cage-free daycare with 70 to 100+ dogs a day, usually with at least 30 together and this is the method we used both to avoid fights as well as correct the behavior. It worked 90% of the time.

Of course, all dogs are different so you never know what will or won't work. It's good to have a few ideas just in case.

I work for an organization where we run small groups - 3-6 - of dogs together every day. IMO it's very different to have 2 or 3 dogs together than it is to have even 5 or 6, so I can imagine it would be exceptionally different with 20 or 30 dogs together. The bigger the group, IME, the easier the dog interractions are, because the dogs can all spread out their attention. With small groups the dogs tend to focus too much on one another and it's more likely for dogs to get picked on or bullied.

Perhaps that's why my method is more effective with a small group.

That's at a dog daycare, with other people's dogs, who are supposed to be completely non-aggressive to begin with... do you think the OP's dog would get accepted into a cage-free daycare exhibiting those aggressive displays? I would hope not. D:

I work at a dog daycare, with 20-40 dogs in each group, and the way I MANAGE those dogs is not even comparable to the advice I would give to their owners to consistently train and desensitize their dogs. In my opinion, all we can do is diffuse tension and keep the dogs safe using distractions, body language, squirt bottles, seperation/timeouts... we can't train some one else's dog and it isn't even worth it to try in that hectic environment. Managing a situation is not the same as training. I see people scruffing, scolding and alpha rolling dogs in daycare and it really, deeply offends me. I've said things about it but it's pretty much accepted by everyone else. I don't feel I have the right to "train" other people's dogs, especially not using +p.

OP, I definitely think it would be a good idea to stop going to the dog park for now (aggressive dogs don't belong there, even resource aggression) and work on giving your dog positive, stress-free experiences with other dogs. He is just now entering social maturity, and most aggressive dogs do not show signs of their aggression until this age. Have one on one playdates in a neutral territory with no posessions, do parallel walking with other dogs, and recognize when your dog is getting guardy and remove him from the situation if you can't control him.

Obedience training will help a lot! As was already said, teaching a very solid recall should help immensely... but you need to make recalling more rewarding than guarding. He shouldn't be freaking out when he sees other dogs. You should teach him to have manners when in the presence of other leashed dogs, even if you have to start practicing from a very long distance. Positive reinforcement based group classes would help a lot to hone his obedience skills around lots of other dogs and make him feel less frantic and excited when meeting new dogs. The book "Click to Calm" by Emma Parsons and "Control Unleashed" by Leslie McDevitt have amazing exercises to change how your dog views and feels around other dogs.