National Implementation Tools

Threat classification systems

Biodiversity management is strongly guided by threat classification systems developed by the International Union for the Conservation of Nature (IUCN) and the Department of Conservation which determine the threat status of species within New Zealand. Threat classification has significant management implications as more care is required to manage impacts on highly threatened species.

Classification of terrestrial environments derived from the Land Environments of New Zealand and the Land Cover Database, enable the loss of habitat types to be identified on a national, regional and local level. This enables the management response to be focused on those habitats of which a high proportion has been lost or which are naturally rare.

In 1963, the IUCN first conceived the Red List System, for formally identifying and classifying species at risk of extinction. The system has evolved considerably since that time, and now includes the results of an assessment of the conservation status of all mammals, birds, amphibians, sharks, reef-building corals, cycads and conifers. Assessments for all reptiles, fish and some groups of plants and invertebrates are also underway. 5124

Assessed species are placed into one of nine categories along a continuum: extinct, extinct in the wild, critically endangered, endangered, vulnerable, near threatened, least concern, data deficient or not evaluated. There are detailed criteria provided for each of the categories. New Zealand species are included in the Red Data List. The categorisation of any species can be obtained through a search on the Red List website at

There is also a New Zealand specific threat classification system which is managed by the Department of Conservation. This was established in 2002 as a result of concern that the criteria used by the IUCN were not necessarily appropriate to the New Zealand situation. Many New Zealand species were naturally restricted in their distribution which meant that their threat status was exaggerated under the IUCN system. 2514

The New Zealand system uses slightly different criteria to the Red List. Evaluated species are first placed into one of four categories; extinct, threatened, at risk, and not threatened. Those that are threatened or at risk are then placed into a further sub-category, depending on the seriousness of their situation. For example, species which are threatened are classified as nationally critical, nationally endangered or nationally vulnerable.

The status of species is reviewed on a three-year cycle. In the 2008-11 cycle, species listings were published in peer-reviewed journals to give them scientific credibility. But copyright issues meant that the lists could not be placed on the Department of Conservation’s website. This made it difficult for people to find out what the conservation status of a particular species was under the New Zealand threat classification system. The information can be obtained by contacting the Department of Conservation directly at In the future, the Department plans to release species threat classifications on its website prior to their formal publication in scientific journals.

Habitat Mapping

Maps of New Zealand’s habitats are currently limited to the Land Environments of New Zealand classification, which maps physical environments, and the Land Cover Database, which describes very broad vegetation classes based on analysis of satellite imagery. When combined, these two products can be used to provide analyses of broad changes in indigenous vegetation cover by environment. Older maps, by the former Forest Service, describe the distribution of native forest classes, but spatial and classification resolution of these maps is too coarse for many applications.

The Ministry for the Environment has prepared maps of land which falls within National Priority 1 for each region and district.

Last updated at 1:14PM on April 11, 2018