Sierra de La Laguna (10090)
Mexico, Central America

Site overview

KBA status: confirmed

Global KBA criteria: A1a, B1

Year of last assessment: 2024

National site name: Sierra de La Laguna

Central coordinates: Latitude: 23.3500, Longitude: -109.9167

System: terrestrial

Elevation (m): 450 to 2090

Area of KBA (km²): 1556.11636

Protected area coverage (%): 78.43

KBA classification: Global

Legacy site: Yes

Site details

Site description: The Sierra de La Laguna is within the Cape Region, located at the southern tip of the Baja California peninsula, Mexico between Los Cabos and La Paz. The Sierra de la Laguna is a mountain range that runs from north to south with a maximum altitude of 2,100 meters above sea level. Major habitats include sarcocaul shrubland, temperate forest and tropical dry forest. These habitat types occur along an altitudinal gradient: sarcocaul shrubland can be found at low elevations. At altitudes from 300 to 1,000 m the only deciduous lowland forest or dry tropical forest on the peninsula can be found, and above this are the holm oak forests and the pine-oak forest. The Sierra la Laguna Biosphere Reserve is divided into two zones: a core zone and a buffer zone. The core zone encompasses the areas of highest elevation in the reserve. The climate is temperate and pine-oak forests are abundant. The buffer zone makes up the lower elevations of the reserve, where the climate is arid and warm. The rainy season is mainly during the summer (August through October), with hurricanes providing one of the main sources of precipitation. Annual precipitation varies between 100-600 mm. There are differences in ambient temperature and humidity between the slopes, with the Pacific coast being more temperate than that of the Gulf of California, due to the influence of the cold California current in the Pacific.

Rationale for qualifying as KBA: The Sierra de La Laguna qualifies as a Key Biodiversity Area as it meets the thresholds of criteria A1a and B1 for Quercus brandegeei, described in the Global Standard for the Identification of KBAs. The site also harbors two bird species (Basilinna xantusii, Colaptes chrysoides) and one plant species (Mammillaria schumannii) as legacy species. Taxonomy, nomenclature and Red List category follow the IUCN 2024 Red List.

Manageability of the site: The Sierra de la Laguna is a UNESCO biosphere reserve. The Sistema Ripario de la Cuenca y Estero de San José del Cabo is a Ramsar Site, Wetland of International Importance. Up to 80% of the KBA is covered by these two protected areas. The authorities responsible for the management of these protected areas are the government of the State of Baja California Sur, the government of the Municipality of Los Cabos, the National Commission of Protected Natural Areas (CONANP), and he National Water Commission (CONAGUA).

Delineation rationale: This site's boundaries follow the edge of the Sierra de la Laguna mountain range and vegetation type (tropical deciduous forest).

Habitats

Summary of habitats in KBA: Vegetation description: In the lower parts of the Sierra La Laguna, on the alluvial plains and the arid mesas, some associations of xeric scrub develop, the most abundant variant of which is the sarcocaule scrub. Located from sea level to between 300 - 500 m altitude. A patch of this plant community occurs marginally in the west and southwest, within the buffer area of the Reserve. In the mid-altitude parts, on the mountainous massif, is the best expression of the dry tropical forest (or low deciduous forest) of the Peninsula, distributed from 450 to 1000 m and covering an approximate area of 58,701 ha. The vegetation consists of a tree stratum, deciduous during the dry season; an equally deciduous shrub and finally a grazing one, composed of both annual and semi-perennial species. In the highest regions of the Sierra there are oak forests (Bosque de Encino, BE) and oak-pine forests (Bosque de Pino Encino, BPE). The BE is located between 800 and 1,200 m. This forest still presents many tropical elements in strata below the upper canopy and occupies about 40,102 hectares of surface in the reserve. The BPE is established in the highest portions of the mountain range from 1,400 m to 2100 m and covers around 8,272 ha. In the deep ravines that characterize these mountain ranges, riparian vegetation also known as gallery forest develops, dominated by palm groves and species from mesic environments from approximately 900 m of altitude and towards the mouth through the stream beds through which water flows all or most of the year. (Breceda et al., 2002). Bosque de Pino Encino (BPE) / Oak Pine Forest: Pine-oak forest, established in the highest portions of the mountains (on the Pacific slope it appears at 1,400 m, while for the Gulf of California it is located at 1,500 m to 2,100 m and covers around 8,272 ha. León de la Luz (1988) points out that the forest is typified by the association of the following physiognomic dominants: black oak (Quercus devia), stone pine (Pinus lagunae), strawberry tree (Arbutus peninsularis) and sotol (Nolina beldingii). beldingii). The proportion of these species varies according to the physiognomic-floristic associations that have been differentiated. This association is basically composed of the four dominant species previously mentioned. Bosque de encino (BE) / Oak forest: Oak forest, located between 800 and 1,200 m. This forest still presents many tropical elements in strata below the upper canopy and occupies about 40,102 hectares of surface in the reserve. It is a community with little vegetation cover, which is not as rich from a floristic point of view as the pine-oak forest. The area included is characterized by its steep slopes and active erosion. This is the most fragile plant community of those that make up the mountain range. The oak is accompanied by several woody species from the low deciduous forest, which although at these altitudes find better humidity levels, are strongly limited by the low temperatures that affect here. In the last three years, temperatures of up to -8°C have been recorded. Bosque Tropical Seco o Selva Baja Caducifolia (SBC) / Tropical Dry Forest or Low Deciduous Forest: Low deciduous and sub-deciduous forest, it is distributed from 450 to 1000 m and covers an approximate area of 58,701 ha. The vegetation consists of a tree stratum, deciduous during the dry season (November-December and February-July); an equally deciduous shrub and finally a grazing one, composed of both annual and semi-perennial species. The latter presents great variability from one year to the next, since it is closely conditioned to the intensity of the rains. Compared to other similar communities, the low deciduous forest of Baja California Sur presents a relatively poor floristic composition with a great influence of species typical of the scrub, mainly cacti. Matorral Xerófilo – (Matorral Sarcocaule) / Xerophilous scrub: Shrublands (sarcocaule), located from sea level to between 300 - 500 m altitude. This type of vegetation houses many characteristic elements of the Sonoran Desert. In the reserve it occupies some small spaces, represented by two communities called: sarcocaule scrub and sarcocrasicaule scrub. Typically, the sarcocaule scrub occurs on surfaces of low elevation above sea level, occupying alluvial plains and low hills. A patch of this plant community occurs marginally in the west and southwest, within the buffer area of the Biosphere Reserve. Bosque de Galería o vegetación riparia / Gallery forest or riparian vegetation: Located along the channels of the main canyons and subsidiary ravines, from approximately 900 m of altitude and towards their mouth through the channels of streams through which water flows all or most of the year. An endemic oak, the Arroyo oak (Quercus brandegeei) occupies the lowest areas of this group, specifically at the level of the low deciduous forest. Herbaceous species are poorly represented and come indifferently from adjacent plant communities.

IUCN Habitat	Coverage %	Habitat detail
Other	5
Forest	20	Forest – Subtropical/tropical dry
Forest	70	Forest – Temperate
Wetlands(Inland)	5	Wetlands (inland) – Permanent rivers/streams/creeks (includes waterfalls)

Threats

Summary of threats to biodiversity at KBA: Within the Sierra la Laguna Biosphere Reserve there are just under a hundred ranches with mainly cattle. The effects of livestock farming on the vegetation of the low deciduous forest has resulted in the loss of diversity of herbaceous species.

Threat level 1	Threat level 2	Threat level 3	Timing
Human intrusions & disturbance	Recreational activities		Ongoing
Energy production & mining	Mining & quarrying		Ongoing
Invasive & other problematic species, genes & diseases	Invasive non-native/alien species/diseases	Named species	Ongoing
Climate change & severe weather	Habitat shifting & alteration		Ongoing
Climate change & severe weather	Droughts		Ongoing
Climate change & severe weather	Temperature extremes		Ongoing
Climate change & severe weather	Storms & flooding		Ongoing
Agriculture & aquaculture	Livestock farming & ranching	Small-holder grazing, ranching or farming	Ongoing

Additional information

References: Breceda Solís-Cámara, A., Quiñónez-Gómez, J. y J. Pérez-Navarro. 2012. Vegetación. En: A. Ortega-Rubio., M. Lagunas-Vázques y L. F. Beltrán-Morales (Editores). Evaluación de la Reserva de la Biosfera Sierra La Laguna, Baja California Sur: Avances y Retos. (pp. 41-53). Centro de Investigaciones Biológicas del Noroeste S.C. 422 pp. CONANP (COMISIÓN NACIONAL DE ÁREAS NATURALES PROTEGIDAS). 2003. Programa de Manejo Reserva de la Biósfera Sierra la Laguna. México. D. F.: Autor, 209 pp.