Biodiversity Hotspots New Zealand

About… New Zealand is an archipelago in the southern Pacific, 2000km south east of Australia Mainly mountainous but has a variety of different landscapes including alluvial plains and forest. Annual rainfall ranges from 12,000 mm (one of the highest rainfall rates in the world) on the western slopes of the Southern Alps, to less than 300 mm in the rain-shadow areas east of the Southern Alps. About 75 percent of the hotspot's land area is above 200 meters in altitude Tectonically Active One of the most diverse places on earth with 1,865 endemic plant species

Why is New Zealand so Diverse? Animal and plant life evolved in isolation for 80 million years, before people arrived, it had the longest period of isolation of any non-polar landmass on earth. Climate is variable, which has affected biodiversity distribution; Kermadec islands are subtropical, whereas Chatham islands are cloudy and humid with cold winters. The different types of climate and habitat means that a huge variety of life can be supported.

New Zealand has extraordinary levels of endemic species. Many of its mammals, amphibians, or reptiles are found nowhere else in the world. Unlike other land masses new Zealand had very few mammals. There are only two endemic land mammals and both are bats. For 65 million years, birds dominated the land. Flightless birds and giant insects (such as the weta) filled roles small mammals filled elsewhere. As a result of evolving with few predators, native species developed strange characteristics such as flightlessness, gigantism and some species became long-lived and slow breeding. For 65 million years, birds dominated the land. Flightless birds and giant insects (such as the weta) filled roles small mammals filled elsewhere.

Endemic Animals

Endemic plants

Human Threats –Habitat Destruction The biggest threats to biodiversity are habitat destruction and invasive species. New Zealand’s temperate forests have been greatly depleted. Native forest has been logged and cleared for pasture. The hotspot originally extended up to and area of 270,197km squared, but has now been reduced to 59,443 km. Forest covered 85% of the island before humans settled, it is now 23%. It has happened in three ways 1)Whole ecosystems have been converted into farmland, exotic forests and settlements. 2)They have been partially removed, creating ‘islands’ surrounded by farmland. 3)Ecosystems have been degraded by the loss of species and disruption of their ecological processes.

Human Threats – Invasive Species Mammals began to arrive in numbers about 1000 years ago in the form of human settlers who bought with them mammal predators such as rats and possums. Without these natural predators, the native species had evolved to be slow, flightless and unprotected, they were easy targets and quickly under threat. For many of the invasive species introduced there were no natural native predators which allowed them to thrive and compete. Invasive species pose the most serious threat to the flora and fauna of New Zealand’s islands, and the hotspot has suffered 50 bird extinctions since the island’s colonization by humans 700 years ago.

Human Impact Many of New Zealand’s native species are now endangered: 63 Endemic Threatened Birds 3 Endemic Threatened Mammals 4 Endemic Threatened Amphibians 23 Extinct Species since 1500

Protecting biodiversity The Department of Conservation manages eight million hectares of land, about 30% of New Zealand's land area. DOC is responsible for preserving and protecting these areas, including managing threats from invasive pests and diseases. To stop the threat of animal pests on native species methods such as introducing natural predators. Ground control -using traps, bait stations or culling -is the most widely used method. The 2008 New Zealand Biodiversity Strategy has been put in place to encourage conservation. They have established marine Protected Areas (MPAs) which ban fishing and allow marine areas to recover from human activity.

Biosecurity Biosecurity is about keeping New Zealand free of unwanted organisms and for controlling, managing or eradicating them should they arrive in the country. This helps to protect and preserve New Zealand’s biodiversity. The Government released New Zealand's first Biosecurity Strategy in August 2003 to deal with the mounting pressures on the biosecurity system. The strategy raises public awareness and understanding of biosecurity.