Biodiversity hotspot

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A biodiversity hotspot is a biogeographic region with a significant reservoir of biodiversity that is under threat from humans.

Norman Myers wrote about the concept in two articles in “The Environmentalist” (1988),[1] & 1990[2] revised after thorough analysis by Myers and others in “Hotspots: Earth’s Biologically Richest and Most Endangered Terrestrial Ecoregions”.[3]

To qualify as a biodiversity hotspot on Myers 2000 edition of the hotspot-map, a region must meet two strict criteria: it must contain at least 0.5% or 1,500 species of vascular plants as endemics, and it has to have lost at least 70% of its primary vegetation.[4] Around the world, 25 areas qualify under this definition, with nine other possible candidates. These sites support nearly 60% of the world's plant, bird, mammal, reptile, and amphibian species, with a very high share of endemic species.

Hotspot conservation initiatives[edit]

Only a small percentage of the total land area within biodiversity hotspots is now protected. Several international organizations are working in many ways to conserve biodiversity hotspots.

  • Critical Ecosystem Partnership Fund (CEPF) is a global program that provides funding and technical assistance to nongovernmental organizations and participation to protect the Earth's richest regions of plant and animal diversity including: biodiversity hotspots, high-biodiversity wilderness areas and important marine regions. CI works in more than 40 countries on four continents, with headquarters near Washington, D.C.[5]
  • The World Wildlife Fund has derived a system called the “Global 200 Ecoregions”, the aim of which is to select priority Ecoregions for conservation within each of 14 terrestrial, 3 freshwater, and 4 marine habitat types. They are chosen for their species richness, endemism, taxonomic uniqueness, unusual ecological or evolutionary phenomena, and global rarity. All biodiversity hotspots contain at least one Global 200 Ecoregion.
  • Birdlife International has identified 218 “Endemic Bird Areas” (EBAs) each of which hold two or more bird species found nowhere else. Birdlife International has identified more than 11,000 Important Bird Areas[6] all over the world.
  • Alliance for Zero Extinction is an initiative of a large number of scientific organizations and conservation groups who co-operate to focus on the most threatened endemic species of the world. They have identified 595 sites, including a large number of Birdlife’ s Important Bird Areas.
  • The National Geographic Society has prepared a world map[7] of the hotspots and ArcView shapefile and metadata for the Biodiversity Hotspots[8] including details of the individual endangered fauna in each hotspot, which is available from Conservation International.[9]

Distribution by region[edit]

Biodiversity hotspots. Original proposal in green, and added regions in blue.

North and Central America

The Caribbean

South America

Europe

Africa

Central Asia

South Asia

South East Asia and Asia-Pacific

East Asia

West Asia

Critiques of hotspots[edit]

The high profile of the biodiversity hotspots approach has resulted in considerable criticism. Papers such as Kareiva & Marvier (2003)[10] have argued that the biodiversity hotspots:

  • Do not adequately represent other forms of species richness (e.g. total species richness or threatened species richness).
  • Do not adequately represent taxa other than vascular plants (e.g. vertebrates, or fungi).
  • Do not protect smaller scale richness hotspots.
  • Do not make allowances for changing land use patterns. Hotspots represent regions that have experienced considerable habitat loss, but this does not mean they are experiencing ongoing habitat loss. On the other hand, regions that are relatively intact (e.g. the Amazon Basin) have experienced relatively little land loss, but are currently losing habitat at tremendous rates.
  • Do not protect ecosystem services
  • Do not consider phylogenetic diversity.

A recent series of papers has pointed out that biodiversity hotspots (and many other priority region sets) do not address the concept of cost.[11] The purpose of biodiversity hotspots is not simply to identify regions that are of high biodiversity value, but to prioritize conservation spending. The regions identified include some in the developed world (e.g. the California Floristic Province), alongside others in the developing world (e.g. Madagascar). The cost of land is likely to vary between these regions by an order of magnitude or more, but the biodiversity hotspot designations do not consider the conservation importance of this difference.

See also[edit]

References[edit]

  1. ^ Myers, N. The Environmentalist 8 187-208 (1988)
  2. ^ Myers, N. The Environmentalist 10 243-256 (1990)
  3. ^ Russell A. Mittermeier, Norman Myers and Cristina Goettsch Mittermeier, Hotspots: Earth's Biologically Richest and Most Endangered Terrestrial Ecoregions, Conservation International, 2000 ISBN 978-968-6397-58-1
  4. ^ Myers, N. et al. Nature (journal) 403, 853–858 (2000)
  5. ^ About Conservation International, retrieved 10/1/2007 CI's Mission
  6. ^ [1][dead link]
  7. ^ "Conservation International". The Biodiversity Hotspots. 2010-10-07. Retrieved 2012-06-22. 
  8. ^ "Conservation International". The Biodiversity Hotspots. 2010-10-07. Retrieved 2012-06-22. 
  9. ^ "Resources". Biodiversityhotspots.org. 2010-10-07. Retrieved 2012-06-22. 
  10. ^ Kareiva, P. and M. Marvier (2003) Conserving Biodiversity Coldspots, American Scientist, 91, 344-351.
  11. ^ Possingham, H. and K. Wilson (2005) Turning up the heat on hotspots, Nature, 436, 919-920.
General references
  • Myers, N., R. A. Mittermeier, C. G. Mittermeier, G. A. B. da Fonseca, and J. Kent. 2000. Biodiversity hotspots for conservation priorities. Nature 403:853-858

External links[edit]

Further reading[edit]