A set of ecoregions whose conservation would achieve the goal of saving a broad diversity of the Earth’s ecosystems and ecological processes. These ecoregions include those with exceptional levels of biodiversity, such as high species richness or endemism, or those with unusual ecological or evolutionary phenomena. ¹ The set of ecoregions aims to be globally representative of the world’s habitats in order to provide a blueprint for conservation which covers all global biodiversity, rather than focusing only on the biomes with the highest species diversity. A total of 238 Global 200 ecoregions have been identified of which 142 (60%) are terrestrial, 53 (22%) are freshwater, and 43 (18%) are marine. ²

The 200 ecoregions were ranked based on their current and future threats and conservation status. At the time of the study (1998), 47% of the terrestrial ecoregions were considered critical or endangered, and 29% were classified as vulnerable. Only 24% of these ecoregions were classified as intact or stable. ¹

Modelling studies investigating the effect of climate change on the Global 200 Ecoregions suggest that more than 80% may suffer extinctions as a result of global warming, with considerable variation between biomes and at different spatial scales. ³ In particular, local biome change is likely to be greatest at high latitudes and altitudes and smallest in lowland tropical ecoregions.

World Wide Fund for Nature (WWF)

1998. The identification of the Global 200 Ecoregions was a one-off process which is not being further updated at this time.

Global in extent, with 238 identified regional-scale areas (142 terrestrial, 53 freshwater and 43 marine). ²

Ecoregions are relatively large units of land containing a distinct assemblage of natural communities and species, with boundaries that approximate the original extent of natural communities prior to major land-use change. These were first classified according to realm (terrestrial, freshwater and marine),  biogeographic realm (e.g. Australasia, Oceania) and major habitat type. Within each biogeographical realm, a set of ecoregions with the greatest biological distinctiveness were chosen based on the following parameters: ¹

• Species richness
• Endemism
• Taxonomic uniqueness (e.g. unique genera of families, relict taxa or communities, primitive lineages)
• Unusual ecological or evolutionary phenomena (e.g. intact large vertebrate faunas or migrations, extraordinary adaptive radiations)
• Global rarity of major habitat type

Global 200 ecoregions are not formally recognised or managed areas, but rather a way of directing conservation efforts for better coverage of biodiversity. Nonetheless, the aim of directing conservation effort and investment toward these areas, as well as their broad scale, means that formal protection and management may be present for sites within these ecoregions.

Legal and compliance - The identification of an area as a Global 200 Ecoregion does not afford the area any legal protection. Legal protection and/or compliance requirements may exist within parts of these areas where there is overlap with other areas of biodiversity importance, such as legally protected areas.

Biodiversity importance - Global 200 ecoregions indicate areas of high biodiversity importance based on the criteria of high irreplaceability of species and habitats within large geographic regions. It is a regional-scale prioritisation approach to assist in conservation efforts world-wide. More detailed assessments are needed to locate the actual distribution of biodiversity within them for any site-scale decision making.

Socio-cultural values - The criteria for identification of Global 200 Ecoregions do not explicitly mention any socio-cultural aspects. However, like other global scale prioritisation approaches, due their large size, people are likely to be involved in use, protection and/or management within parts of these areas.