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These desolate islands are scattered off the south coast of New Zealand, in the southern Pacific Ocean. Scouring westerly winds sweep across the islands unremittingly, and sunlight is extremely variable. Due to the islands’ latitudes, days are shorter in winter and longer in summer. But in any season, sunlight rarely penetrates the thick cloud cover. Vegetation ranges from the sheltered dwarf forests on Campbell Island to the near-barren Bounty Islands, which are little more than lichen-encrusted rocks. These bleak islands have been divided between New Zealand (Auckland, Bounty, Antipodes, and Campbell Islands) and Australia (Macquarie Island), although there are no human inhabitants on any of them, other than the occasional meteorologist.
While the windy and chilly climate has discouraged human habitation, marine mammals and seabirds find these islands welcoming stopover and breeding sites. A wide variety of birds lives here, including mollymawks, shags, and several million erect-crested penguins. Marine mammals such as the New Zealand fur seal, Hooker’s sea lion, leopard seal, and southern elephant seal all come ashore to rest and breed.
Land birds, blown in from Australia or New Zealand, have also colonized these islands. Confined to the islands, the isolated populations of birds have gradually evolved into endemic subspecies. Two different species of brown teal, a flightless waterbird, can be found on the islands, feeding on kelp beds and along small creeks. The Auckland Islands harbor endemic subspecies of rail, tomtit, pipit, and snipe. Seabirds and marine mammals may be present in such abundance that their activity inhibits plant growth. Still, vegetation grows wherever possible on the shallow, peaty, acidic soils. Clumped, hardy tussock grasslands cover rolling summits, where giant megaherbs (herbs with large leaves) belonging to the carrot, daisy, gentian, and forget-me-not families can be found. Some of the plants have flowers that are sheltered from the wind by large, furled leaves. Others resemble small trees, gnarled and twisted by the battering winds and fierce salt spray.
Mammalian predators and grazers have been introduced on all the islands, creating problems for native species. And marine mammals that were once overhunted now face pressure from accidental entanglements in fishing nets. For more information on this ecoregion, go to the World Wildlife Fund Scientific Report. All text by World Wildlife Fund © 2001
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