Environment of New Zealand

The environment of New Zealand is characterised by unique flora and fauna and a variety of landforms contained within a small island nation. Historically having an isolated and endemic ecosystem far into modernity, the arrival of Polynesians about 1280 and then later European settlers began to have significant impacts on this system, with the intentional and unintentional introduction of new species and plants which often overwhelmed their natural competitors, leading to a significant loss of native ecology and biodiversity, especially in areas such as bird life.

Today, most parts of New Zealand are heavily modified by the effects of logging, agriculture and general human settlement, though large areas have also been placed under protection, combined in many cases with efforts to protect or regenerate native ecosystems (aided by the fact that especially the South Island of New Zealand has only a very low population density).

The biota of New Zealand is one of the most unusual on Earth, due to its long isolation from other continental landmasses. Its affinities are derived in part from Gondwana, from which it separated 82 million years ago, some modest affinities with New Caledonia and Lord Howe Island, both of which are part of the same continental plate as New Zealand and in part from Australia.

More recently a component has been introduced by humans. New Zealand's biodiversity exhibits high levels of endemism, both in its flora and fauna. Until recently the islands had no native terrestrial mammals except for bats (although terrestrial, "archaic" mammals did exist in New Zealand until 19 million years ago, in the form of the Saint Bathans mammal), the main component of the fauna being insects and birds. Its flora is dominated by Gondwanan plants, comprising historically of forests, most famously the giant kauri. New Zealand has developed a national Biodiversity Action Plan to address conservation of considerable numbers of threatened flora and fauna within New Zealand.

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