Te Hāwere-a-Maki / Goat Island is listed as a dog park on Great Barrier Island in the Hauraki Gulf Islands, with a Google rating of 4.6.
A good dog park gives dogs room to run and meet others while keeping owners in control. Look for secure boundaries or clear signage, water for the dogs, and shade on warm days. Before you go, check the rules for the specific place, because off-leash areas in New Zealand are often limited and some sites ask for dogs on a lead, especially near wildlife, beaches or protected land. Regulars know to keep their dog's recall reliable, carry bags to pick up after it, and watch how a dog is behaving before letting it join a group. Quieter times of day tend to suit nervous or older dogs better. On an island, it also pays to check local guidance on wildlife and access, as conditions can differ from the mainland.
For visitors and residents on Great Barrier Island, Te Hāwere-a-Maki / Goat Island is a well-rated spot to check out with a dog.