Hi Anna, I just came across this thread. I will attempt to offer you some help.

First realize the characteristics of your beloved Bon's breed. They were bred to protect gamekeepers from poachers. They do have the pack instinct bred into them to protect their prizes. Now couple that with a dog park experience...adrenaline high and excitement in the air....don't be surprised there may be the possiblity of a scuttle or two. But it can be controlled and you are on the right track!

At nine months, Bon is still trying to find who he is. His testostorone is starting to flow and he knows he is strong and confident. You can equate this with a teenage boy. They want to take on the whole world. Bon is going to test the water to see how far he can go and what is acceptable. As long as you remain a strong pack leader this period will pass. You are too be congratulated on letting him know he was out of line and disciplining him by putting him in a sit. Don't be afraid to discipline him again in a more substantial way, for example a long down or even taking him to the car for time out.

I would not stop taking him to the park. I would just make sure of the surroundings and what dogs are around. If there is any possiblity of a scuttle, put the leash on him. Control his greetings in a controlled manner to new dogs. Give him a command to go easy or it's ok. You can even put him in a sit stay until the greeting is made. Make sure it's a solid command understanding on his part. Don't let your guard down but don't be overly apprehensive either. Bon will pick up on your apprehension and he may think he should protect. Just be a strong pack leader and continue in training. If you do, things will be ok.

I'm sure you realize that having him neutered at a young age will help in some of the male to male aggression that may occur. I also know you have decided to wait awhile to do that. I would strongly encourage you to do that if you are not planning on using Bon as a stud dog someday. Once he has stopped growing (height wise) would be a good time.

One last point. If the watering hole is a protective instinct for Bon at the park, then it would be wise to take your own jug of water for Bon to drink from. I always take water to the park for Dixie and Dusty and other dogs that may need it. However, I always have a backpack with me too that has a squirt bottle strictly for my dogs if necessary. They each know how to drink that way. Perhaps you may want to give that a try. Basically, you are trying to forsee any problem that may arise and prevent it.

I can tell you stories about this from my own experiences with Dusty at the dog park! I know he is a golden and they are suppose to be mild mannered but Dusty likes the girls and doesn't like other males near them. I have done the same things I'm telling you and although I still watch for possiblities of scuttles, I can see them coming before they do and will divert Dusty from the situation. He loves the dog park and I want to take him so I just keep on guard as any good pack leader would. Good Luck and let me know if this all makes sense.