The Antipodes Subantarctic Islands tundra ecoregion, within the tundra biome, includes five remote island groups in the Pacific Ocean south of New Zealand: the Bounty Islands, Auckland Islands, Antipodes Islands and Campbell Island groups of New Zealand, and Macquarie Island of Australia.
Location and description
thumb|left|An old [[Castaway depot|castaway hut on the Antipodes Islands.]]
The islands constituting this ecoregion share a long history of isolation, both from other landmasses and each other. The isolation, combined with harsh climates characterised by low temperatures, strong westerly winds and few hours of sunlight in winter, have resulted in the evolution of many endemic plants and animals, though species richness is relatively low. Wind speeds reach an average of while even in summer the thick cloud cover prevents much sunlight from penetrating.
The Bounty Islands are small granite rocks (with a maximum height of ), while the small Antipodes Islands group (maximum height 366 m), the largest group the Auckland Islands () and Campbell Island () are volcanic in origin. Macquarie Island () is the furthest south and the coldest. Where present, soils are mainly boggy peats, up to deep in flat areas. None of the islands are inhabited although there are ongoing research projects including a permanent base of the Australian Antarctic Division on Macquarie Island.
Flora
Vegetation may include low forests of Southern rātā in the more sheltered areas of the Aucklands and parts of Campbell Island, with tussock grassland, shrubland, herbfield, feldmark and cushion plants elsewhere. The islands represent a transition zone between the Antarctic to the south and temperate climates to the north. Individual species include many endemics, such as a Cyathea tree fern, which are not found any further south in the world, along with others that also occur in New Zealand and further north. Macquarie Island, being colder (average annual temperature ), does not sustain any wooded plants, while the small Bounty Islands lack soils and their flora is largely restricted to algae and lichens on the rocks. The islands are home to a number of rare plants, including a unique genus, the Auckland Island Pleurophyllum, and the only subantarctic orchids, Corybas dienemus and Corybas sulcatus of Macquarie Island.