Stewart Island is New Zealand's third-largest island, located 30 kilometres south of the South Island, across Foveaux Strait. It is a roughly triangular island with a land area of 1,746 km². Its 164-kilometre coastline is indented by Paterson Inlet, Port Pegasus, and Mason Bay. The island is generally hilly and densely forested. Flightless birds, including penguins, thrive …Stewart Island is New Zealand's third-largest island, located 30 kilometres south of the South Island, across Foveaux Strait. It is a roughly triangular island with a land area of 1,746 km². Its 164-kilometre coastline is indented by Paterson Inlet, Port Pegasus, and Mason Bay. The island is generally hilly and densely forested. Flightless birds, including penguins, thrive because there are few introduced predators. Almost all the island is owned by the New Zealand government, and over 80 per cent of the island forms Rakiura National Park.