El Pinacate and Gran Desierto de Altar Biosphere Reserve, World Heritage site, Mexico
Located in the Sonoran Desert in northwestern Mexico, El Pinacate and Gran Desierto de Altar Biosphere Reserve (EPGDABR) comprises two distinct parts and harbours a rich trove of biodiversity with many endemic species, including the Sonoran Pronghorn, which is only found in northwestern Sonora and in southwestern Arizona in the United States. To the east lie the dormant Pinacate shield of black and red lava flows and desert pavements, while the Gran Altar Desert stretches to the west with its shifting sand dunes that can reach up to 200 metres in height.
EPGDABR is large, at 714,566 hectares, and relatively undisturbed. Its landscape notably features linear, star and dome dunes, as well as several arid granite massifs, some as high as 650 metres. It also has ten enormous and deep perfectly circular Mar (steam blast) craters, which are believed to have been formed by a combination of eruptions and collapses, and which contribute to the dramatic beauty of the site.
In the west of El Pinacate, the Gran Altar Desert holds North America’s largest field of active sand dunes and its only active Erg (sand sea) dunes. The dunes originate from sediments carried by the nearby Colorado River Delta and other local sources. The dunes are also relatively undisturbed, and include spectacular star-shapes that occur both singly and in long ridges up to 48 kilometres in length. In addition to the impressive dunes and craters, the desert environment includes more than 400 cinder cones, lava flows and lava tubes. EPGDABR was inscribed as a World Heritage site in 2013.
Size and Location
El Pinacate and Gran Desierto de Altar Biosphere Reserve comprises 714,566 hectares, and is located in northwestern Mexico’s Sonoran Desert, close to the border of the states of New Mexico and California in the United States.
Flora and Fauna
The EPGDABR desert areas contain a surprisingly high degree of species diversity across many taxonomic groups of flora and fauna. This includes 44 mammals, more than 200 bird species, 40 reptiles, and over 540 species of vascular plants. Insect diversity is also high, but has not been fully documented. Several of the species are endemic, including two freshwater fish species. Flora includes the unique elephant tree (‘torote’ in Spanish). Native fauna of note are the Sonoran Pronghorn antelope, which is threatened by extinction, and the Lesser Long-nosed Bat.
As a newly inscribed World Heritage site, El Pinacate and Gran Desierto de Altar Biosphere Reserve is relatively undisturbed and shows good standards in terms of management, protection and integrity. Under the authority of Mexico’s Federal Agency for Protected Areas, it is guided by a long-term management plan, with support and active involvement of local governments, NGOs and indigenous peoples.
But with a World Heritage inscription often comes a rise in tourism. To maintain Outstanding Universal Value over time, management will need to be proactive about potential impacts of nearby tourism development and its knock-on effect on the ecological equilibrium. Impact from off-road vehicles has already been observed. Road traffic, littering, wildlife road kills are threats that are likely to increase due to existing or proposed road developments. Pressure to extend the existing road system could also facilitate the entry of alien invasive species.
The most critical long-term management issue is potential problems that can be created by increased water consumption by tourists. Other issues to address include mitigating the impacts from existing or proposed roads, maintaining and enhancing ecological connectivity to buffer against climate change impacts and controlling and eradicating invasive species. EPGDABR would likely benefit from transboundary cooperation with adjoining protected areas in the United States.
Future revisions of the management plan need to include mechanisms for indigenous peoples to be more effectively involved in the Reserve’s everyday management, as well as proposals for financial sustainability options and ways and means to enhance its Outstanding Universal Values and integrity.