Introduction

Six out of the seven sea turtle species known worldwide are found in Mexico: the loggerhead (Caretta caretta), the white, green or “prieta” (Chelonia mydas)¹, the hawksbill (Eretmochelys imbricata), Kemp's ridley (Lepidochelys kempii), olive ridley (Lepidochelys olivacea) and leatherback (Dermochelys coriacea; Dutton et al., 1996; Karl and Bowen, 1999; Chassin-Noria, 2002, Piñero et al., 2008). They nest on the Pacific, the Gulf of Mexico and the Caribbean coasts of Mexico; the Kemp’s ridley breeds exclusively in Mexican beaches.

Sea turtles carry out thousand-mile long migrations and take decades to reach sexual maturity. Because of this, they serve as indicators of the health of coastal and marine environments at local, regional or even global level. They are major components of marine ecosystems, help to maintain the health of seagrass beds, coral reefs, estuaries and sandy beaches, and are important control factors of a number of invertebrate populations (Eckert, et al., 2000; Bjorndal and Jackson, 2003).

For many centuries throughout the world, sea turtles have been exploited to obtain a range of products including meat, eggs, skin, and tortoise shell (in the case of the hawksbill turtle, Eretmochelys imbricata). However, overexploitation of their populations has threatened several of these species with extinction. The main human activities threatening these turtles are bycatch, nest plundering and the kill of females coming out to nest on beaches, in addition to the destruction, pollution or degradation of foraging sites and the destruction or transformation of nesting beaches by coastal development (INP, 2001; Hays, 2003; IATTC, 2007; PNUMA, 2004; Traffic, 2004).

Several mechanisms aimed to protect and restore populations of sea turtle species have been implemented both in Mexico and around the world. Their inclusion in the national list of species at risk, the establishment of beach camps to protect female turtles and their nests, as well as the designation of beaches as natural protected areas, are examples of the government’s efforts to protect and preserve these marine reptiles.

¹ It is debated whether Chelonia mydas (Gulf of Mexico and Caribbean) and C. agassizzi (Pacific) are separate species. Molecular evidence does not demonstrate such a differentiation, so the white and the “prieta” turtle are hereby considered to be one single species (C. mydas, Dutton et al., 1996; Karl and Bowen, 1999 and Chassin-Noria, 2002 in Piñero, 2008). For conservation purposes, the Mexican standard NOM-059-SEMARNAT-2001 considered C. agassizii as a valid separate species (DOF, 2008), contrary to CITES.

References

Bjorndal, K. A. y J. B. C. Jackson. Chapter 10 Roles of Sea Turtles in Marine Ecosystems: Reconstructing the Past. Págs. 259-273. En: Lutz P. L., J.A. Musick y J. Wyneken (Eds.). The biology of sea turtles vol. II. CRC Press LLC. USA. 2003. Disponible en:
http://books.google.com.mx/books?id=IBwouTV8VEwC&printsec=frontcover#v=
onepage&q=&f=false
Fecha de consulta: 30-10-2012.

Dutton D.L., S.K. Davis, T. Guerra y D Owens. Molecular phylogeny for marine turtles based on sequences of the ND4-Leucine tRNA and control regions of mitochondrial DNA. Molecular Phylogenetics and Evolution, 5, 511–521. 1996.

Eckert, K.L., K.A. Bjorndal, F.A. Abreu-Grobois y M Donnelly (Eds.). Técnicas de Investigación y Manejo para la Conservación de las Tortugas Marinas. Grupo Especialista en Tortugas Marinas (Traducción al español). UICN-CSE Publicación número 4. 2000.

Hays, G. C., A. C. Broderick, B. J. Godley, P. Luschi y W. J. Nichols. Satellite telemetry suggests high levels of fishing-induced mortality in marine turtles. Marine Ecology Progress Series 262: 305–309. 2003.

IATTC 75Th Meeting 2007. Disponible en: http://www.iattc.org/ Fecha de consulta: 30-10-2012.

INP. Sustentabilidad y Pesca Responsable en México. Evaluación y Manejo 1999-2000. México. 2001.

Karl S.A. y B.W. Bowen. Evolutionary significant units versus geopolitical taxonomy: molecular systematics of an endangered sea turtle (genus Chelonia). Conservation Biology, 13, 990–999. 1999.

Piñero, D. et al. La diversidad genética como instrumento para la conservación y el aprovechamiento de la biodiversidad: estudios en especies mexicanas. En: Capital natural de México, vol. I: Conocimiento actual de la biodiversidad. Conabio. México. 2008. Págs. 437-494.

PNUMA. Las tortugas del Caribe, próximas a extinción, alerta estudio. 2004. Disponible en:
http://www.pnuma.org/informacion/noticias/2004-11/29nov04e.doc. Fecha de consulta: 30-10-2012.

Traffic. Priority Species: Marine Turtles. 2004.