More than 25% of all bird species have restricted-ranges and occur together in Endemic Bird Areas, including 66% of those considered globally threatened.
Many bird species are confined to small areas of the world’s surface and occur together in ‘centres of endemism’. The unique biodiversity concentrated in these small areas is especially susceptible to the destructive effects of humans. In 1987, BirdLife International started a pioneering project to identify these priority areas for biodiversity conservation, using restricted-range landbirds as indicators. Restricted-range species were defined as those landbirds with a global breeding range of less than 50,000 km2 in historical times (i.e. after 1800, when most ornithological recording began). In total, 2,623 bird species (>25% of the total) were identified as restricted-range species, largely occurring in 218 ‘Endemic Bird Areas’ (ICBP 1992, Stattersfield et al. 1998). In 2008, 815 of these species were classified as globally threatened (66% of all threatened birds) (BirdLife International 2008) (see figure).
Compiled 2004, updated 2008
BirdLife International (2008) Many bird species have very small ranges and occur together in Endemic Bird Areas. Presented as part of the BirdLife State of the world's birds website. Available from: http://birdlife.org/datazone/sowb/casestudy/76. Checked: 31/08/2016
|Key message: Many bird species have small ranges or concentrate at a few key sites|