How well are Mediterranean ecosystems protected in Chile? Insights from gaps in the conservation of Chilean vertebrates P.A. Marquet, M. Tognelli, I. Barria, M. Escobar, C. Garin & P. Soublette Center for Advanced Studies in Ecology and Biodiversity & Departamento de Ecología,Pontificia Universidad Católica de Chile, Casilla 114-D, Santiago, Chile Keywords: Mediterranean-type ecosystems, gap analysis, Chile, vertebrates ABSTRACT: In order to prevent the loss of biodiversity as the result of global environmental changes, it is essential to increase the amount of land within the Protected Area networks currently in place. This is particularly important in Latin American countries, for which this option is proba- bly the safest one considering current demographic trends and short terms threats of a growing and expanding economic activity. The Chilean Protected Area systems was one of the pioneers in Latin America, dating back to 1907, however, as is the case in most countries within the region, most ar- eas were established based on available opportunities rather than following well defined targets and long-term conservation planning strategies. In this contribution, we present the result of Gap Analysis of Chilean terrestrial vertebrates within Chilean Mediterranean area including mammals, birds, amphibians, reptiles, and freshwater fishes in reference to an updated and refined GIS cover of Chilean Protected Areas. In general we found a large number of gap species, especially among species endemic to the Mediterranean area. 1 INTRODUCTION Most ecosystems on earth are in different states of degradation as a consequence of the direct and indirect effect of humans (Vitousek 1994, Hannah et al. 1995, Leemans and Zuidema 1995, Brad- shaw and Marquet 2003). This degradation is manifested in many ways, including substantial modifications in the composition, structure, and functioning of ecosystems linked to local and global extinction of species (e.g., the biodiversity crisis, Wilson 1992 Pimm et al. 1995), alteration of biogeochemical cycles, land transformation, and overexploitation of resources. The impact of humans is so strong and pervasive that current estimates suggest that between one-third to one half of the earth’s land surface has been transformed by human action (Vitousek et al. 1997). Mediter- ranean type ecosystems are subjected to strong threats derived from human activities and harbor a large proportion earth biodiversity and (Cowling et al. 1996, Rundel et al. 1998). Particularly, the Chilean mediterranean ecosystem is recognized as a biodiversity Hotspot (Arroyo et al. 1999, Myers et al. 2000) because of it large diversity of animal and plant species a large fraction of which are endemic. In the context of this global change in the environment the best and least expensive strategy to preserve biodiversity is through the creation of Protected Areas (PA) wherein native species can be protected in the their natural ecosystems. A recent assessment of the global coverage of PAs indi- cates that 11.5% of the land surface is currently protected (Chape et al. 2003). However, there are concerns regarding how this proportion is distributed across the globe and how well it covers bio- 1