Lago de San Juan de los Ahorcados. 02/02/09; Zacatecas; 1,099 ha; 24°01'N 102°18'W. This wetland is a shallow, natural retention, water body with scarce superficial currents. It has great biodiversity and a high level of endemism, including protected species such as Ferocactus pilosus, Hamatacantus uncinatus, Echinocactus platyacanhtus, Peniocereus greggi, Ariocarpus fissuratus, Lephophora williamsi and Coryphanta poselgeriana. The Aquila chrysaetos and other birds of prey nest in the higher parts of the site, and are protected along with other threatened species such as Crotalus molosus, C. atrox and C. scutulatus. This Ramsar Site is part of the Chihuahua Desert, the biggest desert of North America. It is a refuge for migratory birds and its main land uses are agriculture and livestock. Abusive exploitation of the water resource extracted for irrigation is considered to be the main threat to this site. There is a proposal in progress to declare this area a Protected Natural Area in order to regulate the negative impacts of such activities. Ramsar Site n°1920. Most recent RIS information: 2009.