Laguna Chalacatepec. 02/02/2008. Jalisco. 1,093 ha. 19°40'N 105°13'W. This coastal lagoon is representative of the transition regions where biotic elements of the Neartic and Neotropical biogeographic regions come together. Mangroves are the predominant vegetation, including the species Laguncularia racemosa, Rhizophora mangle, Conocarpus erectus y Avicennia germinans. Important populations of the American Crocodile (Crocodylus acutus) have been found in this site, as well as the presence of the Southern River Otter (Lutra annectens), a threatened species according to the Mexican normative. This lagoon is essential for the reproduction of resident waterfowl such as Nyctanassa violacea, Ardea alba, Egretta thula, y Phalacrocorax brasilianus, and is used by migratory waterfowl (Anas acuta, Fulica Americana y Dendrocygna aututumnali) as a staging point for eating and resting on their long-distance journeys. The main activities undertaken are local fishing, agriculture and extensive livestock in the surroundings.This site lies adjacent to the Marine Turtle Sanctuary El Playuón de Mismaloya, dedicated mainly to the conservation of marine turtles, activity that is becoming more and more popular as a touristic attraction, and helping to create awareness regarding the importance of the protection of natural resources.