Introduction

Mexico is one of the most biologically rich countries in the world, in terms of ecosystems, species and genes. Harbouring approximately 12% of the planet's biodiversity, Mexico is one of the 12 mega-diverse countries of the world, along with Brazil, Colombia, Indonesia, Peru, India and Australia, among others (Conabio, 2006). Currently, over 100 thousand different species are known to inhabit the Mexican territory, about 32 000 of which are plants and fungi and the rest are a diverse assemblage of animals (Llorente-Bousquets and Ocegueda, 2008). Mexico ranks in the five richest countries in the world as to numbers of plant and amphibian species, first for reptile species and third for mammals (Espinosa et al., 2008).

Another distinctive feature of Mexican biodiversity is its high degree of endemism, i. e., the number of species that can only be found within its territory. Amphibians stand out in this regard, with about 48% of its species being endemic to Mexico, followed by reptiles (46%) and cacti (50%) (Llorente-Bousquets and Ocegueda, 2008).

This species richness supplies multiple goods and services to society: food and raw materials for manufacturing various products, energy generation and as a source of active ingredients for pharmaceuticals, among many others (UNDP, UNEP, WB and WRI, 2000; Groombridge and Jenkins, 2002; Ranganathan, 2008; Balvanera, Cotler et al., 2009). When species are assembled into diverse, highly complex ecosystems, they also provide a range of valuable environmental services such as water filtration and purification; protection of coastal zones; regulation of climate and the hydrological cycle; soil formation and conservation; waste dispersion and degradation; pollination of crop plants; and absorption of pollutants, among the most important ones (Ehrlich and Ehrlich, 1992; UNEP, 2007; CBD, 2005; UE, 2006).

As in many other countries, Mexico's biodiversity faces serious threats. To date, several dozens of plant and animal species have become extinct in the territory, while hundreds others are at risk. The conversion of natural ecosystems into productive systems (farms, rangeland and aquaculture farms); overexploitation of wild populations; illegal exploitation; soil, air and water pollution; and the introduction of exotic species are some of the activities that most severely impact biodiversity (Arriaga et al., 1998, 2000, Sánchez-Colón et al., 2009).

To preserve this vast natural wealth, a number of protection and recovery strategies have been implemented over the years. The National System of Protected Natural Areas, the Payment for Environmental Services schemes, the various Programs for Wildlife Conservation and Recovery of Priority Species, the establishment of Management Units for Wildlife Conservation (Uma, for its acronym in Spanish), and many regulatory, inspection and surveillance efforts are just some examples.

This section presents indicators that describe the major factors threatening the country’s plant and animal species, and some others that describe their current state as well as the measures taken to halt and reverse some of those impacts. Although these indicators address overall biodiversity, additional indicators for particularly important or critically imperiled species groups are also presented. This is the case of sea turtles and some cetacean species (e. g., gray and humpback whale and vaquita) that visit or inhabit the country’s waters.

References

Arriaga C., L., E. Vázquez-Domínguez, J. González-Cano, R. Jiménez R., E. Muñoz L. y V. Aguilar S. Regiones Prioritarias Marinas de México. Conabio. México. 1998.

Arriaga C., L., V. Aguilar S. y J. Alcocer D. Aguas continentales y diversidad biológica de México. Conabio. México. 2000.

Balvanera, P., H. Cotler et al. Estado y tendencias de los servicios ecosistémicos. En: Capital Natural de México, vol. II: Estado de conservación y tendencias de cambio. Conabio, México, 2009.

CBD. International day for biological diversity - 22 may. 2005. Disponible en: http://www.cbd.int/ibd/2005/ Fecha de consulta: 30-10-2012.

Conabio. Capital Natural y Bienestar Social. México. 2006.

Ehrlich A. H. y P. R. Ehrlich. Causes and consequences of the disappearance of bidiversity. En: Sarukhán, J. y R. Dirzo (Comps.). México ante los retos de la biodiversidad. Conabio. México. 1992.

Espinosa, D., S. Ocegueda et al. El conocimiento biogeográfico de las especies y su regionalización natural. En: Capital Natural de México, vol. I: Conocimiento actual de la biodiversidad. CONABIO, México. 2008.

Groombridge, B. y M. D. Jenkins. World Atlas of Biodiversity. UNEP WCMC. University of California Press. USA. 2002.

Llorente-Bousquets, J., y S. Ocegueda. Estado del conocimiento de la biota. En: Capital Natural de México, vol. I: Conocimiento actual de la biodiversidad. Conabio. México. 2008.

Ranganathan,J., K. Bennett, C. Raudsepp-Hearne, N. Lucas, F. Irwin, M. Zurek, N. Ash y P. West. Ecosystem Services: A Guide for Decision Makers. WRI. 2008.

Sánchez Colón, S., A. Flores Martínez, I.A. Cruz-Leyva y A. Velázquez. Estado y transformación de los ecosistemas terrestres por causas humanas. En: Capital Natural de México, vol. II: Estado de conservación y tendencias de cambio. Conabio, México. 2009.

UE. Plan de acción para en favor de la biodiversidad. 2006. Disponible en:
http://europa.eu/legislation_summaries/environment/nature_and_biodiversity/l28176_es.htm
Fecha de consulta: 30-10-2012.

UNDP, UNEP, WB y WRI. World Resources 2000-2001. Washington DC, 2000.

UNEP. Informe Anual del PNUMA. 2007. Disponible en:
http://www.unep.org/PDF/AnnualReport/2007/UNEP_AR_2007_SP.pdf Fecha de consulta: 30-10-2012.