Aggressive Jack Russell/Rat Terrier Mix
We adopted our dog when he was 3 months old. He has always loved playing with other dogs and has not been overly friendly but accepting of strangers (human). Recently while off leash he has run off to chase up to a person and bark at them, while circling them. These people have made no move to interact with the dog. He has never bitten someone but barks incessantly at them. He has just started to randomly do this at the dog park, choosing one dog and then "harrassing" that dog with non-stop barking. Help!