HELP - Tommy is getting more and more aggressive

Tommy will be celebrating his first birthday on Thursday and I should be getting ready to post pics of him with a party hat on. Instead I'm having to post about him getting aggressive when approached by other dogs when he is on the lead. It's now getting to the stage where he doesn't even allow an introductory sniff.
He also appears very nervous when walking on the lead. I've tried taking his favourite treat out with us but he just ignores it. I think it is fear of other dogs that is causing it as after we have moved away he pulls to put as much distance between himself and the other dog as possible.
This morning a male boxer approached us, no owner in sight! Anyway he started growling and pulling; I held him back and tried to walk away but the boxer just followed us. Tommy continued to bark and the boxer then growled a little. By this point i was holding Tommy so far back that he was off the floor. He then slipped his harness and I managed to grab his collar before he could get to the boxer. I picked him up in an effort to restrain him and he bloody boxer just carried on trying to jump at him. At this point the owner of the boxer walked round the corner without a care in the world. I gave him an earful and told him that he needed to have us dog under supervision to which he replied that his dog doesn't have an aggressive bone in his body.
I'm getting worried that I'm going to end up with a dog who snaps and snarls at everything that walks past him. We will have to go to the vets soon for a check up and the waiting area is going to be a nightmare as I know he'll start snarling at the other dogs.
I've tried rewarding good behaviour, tried taking his favourite treats, tried the look at me technique. Nothing seems to work with him.
Do you think a behaviourist will be able to help?
PS - it seems to have coincided with us moving house a couple of months ago

some dogs just dont like other my sam doesn't like bigger dogs but love smaller dogs, has he been attack in the past?

Nope, he's never been attacked and was socialised really well. Now I daren't let him off lead to greet another dog. He's fine with bitches tho.
It's the nervousness on the lead which is concerning me tho.

Chloe began growling at other dogs with her hackles up when she was about 10 months, but only when she was on the lead. Off the lead she was fine. I was a bit despairing to be honest, but it suddenly stopped when she got to about 15 months. I think it was because she felt threatened when she was on a lead, as in she couldn't run away if needed, although I'll never be sure. Hopefully it's a phase Tommy is going through, although I understand your concern. We've got two, so I guess we didn't feel that it was something we'd done wrong, as the other one was behaving perfectly. So, don't think you've not trained him correctly - hopefully it's just him growing up and finding his feet  

Has he been neutered & if so, when?

Frankie often barked and growled while on the lead. He does this because he gets nervous due to in the past having big groups of dogs bombard him and he can't get away. I can now get him in a sit and stay until they walk past.
I use liver cake. As soon as I saw a dog I would reward him, no matter how far away it was. And then keep rewarding until the dog went past. It took a while, and I had to learn what his safe distance was. Now he doesn't react like that. He trusts me and has realised that seeing dogs was a positive thing. Have you got friends with 'bomb proof' dogs you could practice with? Sounds like you need to go back to basics with training. As said above some dogs just don't like other dogs and some just react on leads. If this is the case please don't give up, this can be managed so that you both enjoy walks

Am afraid staffys are a breed that as they mature CAN suddenly take a dislike to other dogs, no matter how well they are socialised

Caryll wrote:Has he been neutered & if so, when?

He's not been neutered. For every person that says it calms them down, I've heard another say it doesn't make any difference. I've also read that they get a secondary growth spurt at around 18 months so was waiting until after this to get him "done".

Bloomooner wrote:

Caryll wrote:Has he been neutered & if so, when?

He's not been neutered. For every person that says it calms them down, I've heard another say it doesn't make any difference. I've also read that they get a secondary growth spurt at around 18 months so was waiting until after this to get him "done".

i'd definitely leave as long as possible until he's mentally and physically mature before neutering if that's what your set on

Mandz wrote:Frankie often barked and growled while on the lead. He does this because he gets nervous due to in the past having big groups of dogs bombard him and he can't get away. I can now get him in a sit and stay until they walk past.
I use liver cake. As soon as I saw a dog I would reward him, no matter how far away it was. And then keep rewarding until the dog went past. It took a while, and I had to learn what his safe distance was. Now he doesn't react like that. He trusts me and has realised that seeing dogs was a positive thing. Have you got friends with 'bomb proof' dogs you could practice with? Sounds like you need to go back to basics with training. As said above some dogs just don't like other dogs and some just react on leads. If this is the case please don't give up, this can be managed so that you both enjoy walks

Unfortunately I don't know anyone with a dog which is so "bomb proof"! I'll try to get back to basics with the training but he just wants to get away from the situation. Even little pieces of cheese, which he will usually do anything for, don't interest him. I just can't seem to get his attention.
Out of interest he was off lead this morning and running alongside a springer spaniel without a care in the world. Difference being she was a bitch...
Thanks again for the reassurance, I'm hoping he grows out of it!

jo garnett wrote:Chloe began growling at other dogs with her hackles up when she was about 10 months, but only when she was on the lead. Off the lead she was fine. I was a bit despairing to be honest, but it suddenly stopped when she got to about 15 months. I think it was because she felt threatened when she was on a lead, as in she couldn't run away if needed, although I'll never be sure. Hopefully it's a phase Tommy is going through, although I understand your concern. We've got two, so I guess we didn't feel that it was something we'd done wrong, as the other one was behaving perfectly. So, don't think you've not trained him correctly - hopefully it's just him growing up and finding his feet    

Thank you for your input, hopefully it is just a phase he's going through and I know his hormones will be racing too. I'm thinking stroppy teenager at the moment