Do plott hounds tend to be territorial and prone to aggression?

I never even heard of a plott hound until 4 weeks ago. I took this little guy in after I was unable to successfully locate his owners.

He gets along well with my 2 yr old dog, but he is aggressive with other dogs he meets at the dog park. He will steal toys and then start fights with the dog(s) when they try to retrieve their toys (growling, showing teeth, trying to bite). It's more than just typical puppy behavior. He can be overly aggressive.

He is not neutered yet, as the vet advised against it at this age. He just started obedience training and I am told that he will probably come out of this stage, but I wonder . . .

From what I have been told and from what I have researched, these dogs are generally used for hunting and not kept as pets.

Does anyone have a plott hound that could share his/her experiences with me?