You should not be taking your dog to a dog park. He is not showing stable temperment, and this is putting him, you, and others in jeapordy. Because this "aggressive" behavior, by your account, has just started suddenly, he needs to be fully screened by a vet.
Once the vet has ruled out medical conditions, I would have a dog behaviorist (NOT a dog trainer!) observe and evaluate him to see what is going on and what should and can be done to modify and correct the problem.
Dog parks should be off limits. His behavior can lead to a serious dog fight, in which he, you, and multiple other dogs and people can be severely injured and even killed. This can be very serious. |