Closing the gap: creating ecologically representative protected area systems: a guide to conducting gap assessments of protected area systems for the Convention on Biological Diversity
Dudley, Nigel
,
Parish, Jeffrey
2006
The earth is currently facing the real possibility of permanently losing a vast number of wild plant and animal species in an "extinction crisis" that is unparalleled in history for its speed and severity. The CBD estimates extinction rate as 100-200 times higher than the historical natural level, with the greatest losses on islands and in freshwaters1, while the United Nations Environment Programme also identifies forest species as being particularly at risk2. The Millennium Ecosystem Assessment is more pessimistic and believes that extinction rate may be up to a thousand times above historical levels. Drawing on IUCN Red Data List material3, it estimates that for instance 12 per cent of bird species and 23 per cent of mammals are threatened with extinction. Just as significant, studies suggest that almost all species are currently declining in either range and/or population size and all ecosystems are declining4.
