The importance of conserving biodiversity outside of protected areas in mediterranean ecosystems.
Mediterranean-type ecosystems constitute one of the rarest terrestrial biomes and yet they are extraordinarily biodiverse. Home to over 250 million people, the five regions where these ecosystems are found have climate and coastal conditions that make them highly desirable human habitats. The current conservation landscape does not reflect the mediterranean biome's rarity and its importance for plant endemism. Habitat conversion will clearly outpace expansion of formal protected-area networks, and conservationists must augment this traditional strategy with new approaches to sustain the mediterranean biota. Using regional scale datasets, we determine the area of land in each of the five regions that is protected, converted (e.g., to urban or industrial), impacted (e.g., intensive, cultivated agriculture), or lands that we consider to have conservation potential. The latter are natural and semi-natural lands that are unprotected (e.g., private range lands) but sustain numerous native species and associated habitats. Chile has the greatest proportion of its land (75%) in this category and California-Mexico the least (48%). To illustrate the potential for achieving mediterranean biodiversity conservation on these lands, we use species-area curves generated from ecoregion scale data on native plant species richness and vertebrate species richness. For example, if biodiversity could be sustained on even 25% of existing unprotected, natural and semi-natural lands, we estimate that the habitat of more than 6,000 species could be represented. This analysis suggests that if unprotected natural and semi-natural lands are managed in a manner that allows for persistence of native species, we can realize significant additional biodiversity gains. Lasting biodiversity protection at the scale needed requires unprecedented collaboration among stakeholders to promote conservation both inside and outside of traditional protected areas, including on lands where people live and work.
The Nature Conservancy, San Francisco, California, United States of America. rcox@tnc.org
Robin L
RL
Cox
Emma C
EC
Underwood
D000818:Animals; D044822:Biodiversity; D003247:Conservation of Natural Resources; D016208:Databases, Factual; D017753:Ecosystem; D006801:Humans; D019083:Mediterranean Region
Conserv Biol. 2008 Dec;22(6):1380-1
19076870
PLoS One. 2009 Jul 29;4(7):e6392
19641600
Proc Natl Acad Sci U S A. 2008 Apr 29;105(17):6498-501
18413614
Proc Natl Acad Sci U S A. 2009 Sep 8;106(36):15368-73
19717457
PLoS One. 2008 Jan 30;3(1):e1515
18231601
Trends Ecol Evol. 2005 Aug;20(8):430-4
16701413
Trends Ecol Evol. 1996 Sep;11(9):362-6
21237880
Nature. 2000 Feb 24;403(6772):853-8
10706275
Conserv Biol. 2009 Feb;23(1):43-52
18950475
PLoS One. 2008 Jun 25;3(6):e2502
18648541
Conserv Biol. 2009 Oct;23(5):1080-9
19549219
Nature. 2006 Mar 16;440(7082):337-40
16541073