Is this serious dog agression? HELP!
Before I start, I know this is MY fault. (Please excuse my rambling, but I want you to get a feel of my dog before I go into the problem we are having.)
With that being said, I have a 3 year old male GSD that goes by the name of Tank. He is a decently mannered dog. He always gets compliments on how well behaved he is, which he is, unless he is overly excited. Tank is also the type to cause a ruckus just to spite me.
He has never been great on a leash. (My fault, I know...) Pulls a lot, but we are working on that. It makes it harder that he is now big enough to drag me around (which he has), but we are still trying regardless. A gentle leader was suggested by someone, so I just purchased that and I'm going to give it a try.
Up until the past year, he has been a well socialized dog. He has always been a little rough(playful) with other dogs, but never to the point of questioning it to be agressive behavior. Due to roommates, Tank has shared his home with 2 dogs before. One came in as an adult and the other as a puppy. Tank had no issues with them. Recently, I took Tank around a friends puppy. He was of course extited, and the whole time I felt on edge as if something bad would happen. Tank lunged at the dog and snapped at him... it didn't seem to be a mean bite, but it didn't seem like a nice playful one either. I don't know how else to describe it? Tank made a yapping noise as he bit at the puppy, but I quickly pulled him away. He tried this a few times to the point where I felt uncomfortable.
We have added a puppy to our household since then. Tank did the same thing with the puppy, but I corrected him every time. (Usually a firm NO works with our puppy, but not with outside situations) He is fine with her now, though I would not yet leave them together unsupervised.
We ventured out to the dog park yesterday, where Tank saw 2 other dogs coming out. He immediately started barking and pulling to get to them. When we got to the dogs, Tank was really only interested in sniffing one of them(who appeared to be just under a year old). Without fail, Tank did the yap/bite a few times with this dog.
I am hoping my explanation of this behavior is understandable and I hope there is a way this can be resolved. Tank is eager and willilng to learn, he has just recently learned to WAIT(otherwise known as STAY to some) when asked. I want to be able to take him around other dogs without being in fear that he is going to attack at any second. Can anyone offer some sort of advice?