Special Information

The high abundances of red knot observed at the salt mine motivated different researchers to visit the site (October 2006) with the intention of conducting the first banding effort of this species in Mexico. At the end of October 2006, the researchers met at concentration area Salitrales 1A: six from outside Mexico (N. Clark, H. Sitters, R. Robinson and J. Clark from England, and B. Harrington and N. Atkins from the United States) and 10 from Mexico (all within the Bird Program at the Autonomous University of Baja California Sur, under the direction of Roberto Carmona). They captured and banded 194 red knots, presumably of the subspecies C. c. roselaari, and adults predominantly (83%). The observed results confirmed that the Guerrero Negro salt mine is a site of major importance for this species in Mexico. Also, the re-observation of banded birds has begun to give researchers a description of this subspecies’ migratory routes. For example, recent data confirm the presence of banded birds not only at the salt mine but also on the coasts of Washington and Alaska. It is expected that this banding effort will be repeated in October 2007, fundamentally with participation from the same researchers. Other ornithological studies carried out at the Guerrero Negro salt mine exist, of which the following stand out:
  • Danemann and Carmona (2000) determined the species of birds that reproduce within the salt mine installations are: Falco peregrinus, Sternulla antillarum browni, Passerculus sandwichensis, Pandion haliaetus, Charadrius alexandrinus, Haematopus palliatus, Hydroprogne caspia, Thalasseus maximus, Gelochelidon nilotica and Rynchops niger. The first three are protected by the Mexican Government (under categories of special protection, in danger of extinction, and threatened, respectively). For the last two species listed, this is the first register of their reproduction in Baja California Sur.

  • Carmona and Danemann (2000) determined the temporal abundances of four species of Pelecaniformes (Pelecanus erythrorhynchos, P. occidentalis, Phalacrocorax auritus and Ph. penicillatus) at the salt mine. The most abundant species was Ph. auritus, followed by P. erytrhorhynchos and P. occidentals; Ph. penicillatus was observed only occasionally. This work demonstrates that the salt mine is an important point for the post-reproductive dispersion of these species.

  • Peralta et al. (2002) studied the ecological attributes of 13 species of resident waterbirds at the salt mine. The most abundant species was Phalacrocorax auritus, and the species most widely distributed was Larus occidentalis. Peralta found evidence of a negative relationship between the richness and abundance of these species and salinity.

  • Peralta et al. (2004) studied the depredation of the western gull (Larus occidentalis) on the eared grebe (Podiceps nigricollis) within the salt mine. Some 35 successful attacks were registered—the first ever of such recordings for grebes.

  • Cuéllar-Brito (in revision) studied the attributes of the eared grebe’s (Podiceps nigricollis) migratory use of the salt mine, and registered up to 16,000 wintering grebes there. The sex ratio was 1:1, and adults outnumbered sub-adults and juveniles. Depredation on grebes by gulls was also observed (in fact, 6% of the population was depredated), but the gull species involved was always the herring gull (Larus argentatus).
Site Facts

Country,State,
Province/Region:
Mexico, State of Baja California Sur
Municipality of Mulegé

Relative Location:
The site is located in the western half of the Baja California Peninsula, Mexico. It is within the Sebastián Vizcaino Bay, borders the Ojo de Liebre Lagoon, and is part of the El Vizcaíno Biosphere Reserve.

Latitude/Longitude:
27º 42’ 30" N; 113º 56’ 30" W

Category:
International

Basis for Designation:
The site is utilized by at least 100,000 shorebirds over the course of a year

Size:
20,102 hectares (49,673 acres)

Joined:
September 19, 2000

Site Owner/Steward:
The property belongs to the Benito Juárez and Gustavo Díaz Ordaz Ejidos, however through a Temporary Occupation Agreement it is being utilized by the company Exportadora de Sal, S.A. de C.V, via a Mining Concession granted by the Federal Government

Site Partners:
Autonomous University of Baja California Sur, El Vizcaíno Biosphere Reserve, Exportadora de Sal, S. A. de C. V., and Pronatura Noroeste.

Human Population within 100 km:
Guerrero Negro (12,000 inhabitants)

Contact:
Roberto Carmona, Autonomous University of Baja California Sur, beauty@uabcs.mx ;

Nallely Arce, Autonomous University of Baja California Sur, nallely_arce@hotmail.com;

Martín Domínguez, Exportadora de Sal, mdominguez@essa.com;

Martín García Aguilar, Exportadora de Sal, amgaguilar@hotmail.com;

Benito Bermúdez, El Vizcaíno Biosphere Reserve, bermudez@conanp.gob.mx;

Gustavo Danemann, Pronatura Noroeste, gdanemann@pronatura-noroeste.org