As well as the three main islands (the North and South islands and Stewart Island), New Zealand's territory includes three remote groups of offshore islands: the Kermadec Islands in the north, the Chatham Islands to the east, and the subantarctic islands in the south.
The Kermadec Islands are the only part of a chain of huge volcanoes that have emerged above the sea, more than 1,000 kilometres north-east of the North Island. From north to south, they are Raoul (or Sunday) Island, Macauley Island, Curtis Island, and L’Esperance rock. The largest, Raoul Island, has erupted several times within the historic record, most recently in 2006.
All the islands are scientific reserves, and have restricted access. Raoul Island has New Zealand’s northernmost meteorological station. It is covered in broadleaf forest, mainly pōhutukawa.
Goats were released on Raoul and Macauley islands in the 19th century to feed shipwrecked sailors, and have badly damaged the vegetation – Macauley Island now resembles a grassy meadow. Goats were eradicated at the end of the 20th century, and the plants are slowly recovering.
The Chatham Islands are geologically part of New Zealand, but are 800 kilometres east. They lie on a long finger of continental shelf that reaches eastward from the South Island. Low-lying and windswept, the islands’ traditional Moriori name, Rēkohu, means ‘misty shores’.
There are four main islands – Chatham, Pitt, Rangatira (also called South-East Island) and Māngere – as well as many small rocks and reefs. Only Chatham and Pitt are inhabited.
The largest island, Rēkohu or Chatham Island, has long sandy beaches and a flat or rolling landscape, covered in thick peat. Nearly a quarter is occupied by shallow lakes and lagoons, and the central Te Whanga lagoon looks like an inland sea. Formerly a deep bay, it has been enclosed by sand dunes on the eastern side, but occasionally opens to the sea. Its water is brackish. Conspicuous volcanic cones and plugs dot the north end of the island, and the southern end is formed of ancient volcanic rock.
Pitt (Rangiauria) Island is much smaller than Chatham, but more rugged. It is ringed with cliffs. Rangatira and Māngere islands are free of introduced mammals, and are important sanctuaries for threatened species.
The subantarctic islands consist of five island groups (the Snares, Bounty, Antipodes and Auckland islands, and Campbell Island) scattered over the ocean south of New Zealand. The Auckland Islands and Campbell Island are remnants of ancient volcanoes, but the others are made of granite that lies under the huge submarine Campbell Plateau.
There were several unsuccessful attempts to settle the islands for sealing and farming. They are now nature reserves and a World Heritage Area. The United Nations Environment Programme has described them as the most diverse and extensive of all subantarctic archipelagos, and they have a wide range of wildlife, especially birds. Landing on the islands is strictly controlled.