Conservation Targets: Do They Help? By Michael E. Soulé & M. A. Sanjayan; Science, New Series, Vol. 279, No. 5359. (Mar. 27, 1998), pp. 2060-2061.
The most irreversible environmental problem of this era is the projected rapid loss of biodiversity, including the disappearance of up to half the world’s species. In response, many international commissions and nature conservation organizations have called for the near-term protection of at least 10 or 12% of the total land area in each nation or in each ecosystem. If successful, this campaign would double or triple the land area now designated as national parks or similar strict reserves. We are concerned, however, that these target percentages could become de facto ceilings of protection and imply that protecting 10% or so of the land is sufficient to prevent the predicted major extinction event.