Harsh desert conditions coupled with intense heat conspire in limiting human settlements along the coast of the Baja California Peninsula in the Gulf of California, resulting in a haven for natural diversity which is plentiful and breathtaking. Right after the rainy season, in December 2019, a team of 86 researchers from a variety of disciplines went to the field to comprehensively detail the biodiversity and conservation status of a unique location: the bay of San Basilio. 

The bay of San Basilio is immediately remarkable to any visitor for its stunning landscape and heterogeneity of landforms and habitats. This secret corner of the peninsula quietly boasts abundant natural resources and phenomenal biodiversity. The whole bay is alive, above and below the rich lands and waters of this coastal paradise. The marine elements include rocky reefs, and both sandy and rocky shores, which span an ecotone of taxonomic biodiversity. The land-sea fringe is home to mangroves, salt-marshes, dunes and estuaries. The influences of land and sea support the presence of a plethora of coastal species, and further inland a healthy arid scrub complex with seasonal lagoons and permanent freshwater pools is home to several rare and endangered species, and elevated numbers of species in general.  [Download the bilingual report here]

The team recorded 1,333 observations of different species belonging to 476 different taxa. Of these, around 80 species found in San Basilio area are currently protected or considered under threat by the NOM-059-SEMARNAT-2010 and the IUCN.  But this amazing richness remains threatened. Biodiversity at the coast is impacted by the presence of humans and free-roaming dogs. Tourism is putting considerable pressure on the coastal habitats. Overfishing, through both industrial harvest and unsustainable take of top predators (e.g., sharks and groupers) is adversely affecting the marine ecosystems. Cattle are reducing the inland terrestrial biodiversity and abundance. The findings from this expedition link the conservation challenges of marine and terrestrial biodiversity, with recommendations for the long-term conservation of the San Basilio region.