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Ajos-Bavispe National Forest

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Ajos Bavispe National Forest & Wildlife Refuge

Ajos-Bavispe is one of Mexico's oldest protected areas. Decreed almost 70 years ago, the reserve was created to preserve eight mountain tops, or "sky islands." These sky islands are high elevation communities of high biodiversity, separated from each other by desert or grassland valleys. Decades ago, the Mexican federal government recognized the importance of preserving these mountain tops as key to ensuring the health of the watersheds for three of the most important rivers in the state of Sonora -- the Sonora River, the Bavispe-Yaqui River and the San Pedro River. These rivers provide drinking water for a growing population and are key to the agricultural productivity of the region. Due to the ruggedness and inaccessibility of the mountains, the reserve's sky islands remain refuges for biodiversity, including many endemic species.

did you know?

Ajos-Bavispe is a fire-maintained system. Similar ecosystems in the U.S. have undergone significant ecological changes due to fire suppression, but at Ajos, the natural fire regime remains largely intact. In fact, the reserve serves as an example of desired future conditions for restoration projects at similar sites in the U.S.

Sierra los Ajos

Sierra Los Ajos in the San Pedro River basin
© Adriel Heisey


site profile

total area protected:
456,382 acres
map of site

Sierra Madre Occidental Pine-Oak Forest

partner organization:
Comisión de Ecología  y Desarrollo Sustentable del Estado de Sonora (CEDES) 









Ecological Importance

The healthy pine, pine-oak, and oak forests and chaparral of Ajos-Bavispe are prime habitat for a diversity of species including 1,234 species of vascular plants, 208 species of birds and 156 species of butterflies. Among the important species are black bear, peregrine falcon, golden eagle, porcupine and rare and threatened species such as the Mexican spotted owl, leopard frogs, thick-billed parrot, and horned lizard.


Due to its ruggedness, the reserve has remained largely protected. The most significant threats to the refuge are natural fire regime change through fire suppression programs, illegal cattle ranching and associated introduction of invasive species, road construction, and illegal timber harvesting and wildlife poaching.

A Strategy of Success

Although Ajos-Bavispe was designated a reserve in 1939, it did received the attention it deserved until 1998 and for six decades the area was impacted by logging, mining, cattle grazing and hunting. When PiP began funding, the program focused site consolidation efforts on improving basic operations of the park, including the hiring and training of staff, improving and building infrastructure, purchasing equipment, and strategic conservation planning. With these improvements Ajos-Bavispe has improved its threat score from “medium” to “low.”

The PiP partner organization, BIDA, is drafting an integrated fire management plan for the reserve one of the first in Mexico. The plan will be used to educate public agencies and local people on the important role of fire in maintaining the health of the watersheds and the forests and surrounding grasslands as well as to prevent catastrophic fires, such as those recently experienced in the U.S. in similar fire-maintained ecosystems.

Working with The Nature Conservancy in the U.S., PiP helped IMADES develop key programs for private lands and freshwater conservation techniques to promote watershed-management bi-nationally.

Read more about Ajos-Bavispe...

Comisión de Ecología y Desarrollo Sustentable del Estado de Sonora (CEDES) 

Read more about projects in Mexico...

El Pinacate/Gran Desierto del Altar Biosphere Reserve
Cuatro Ciénegas National Wildlife Reserve

Loreto Bay/Isla Espiritu Santo Migratory Flora and Fauna Reserve
Ría Celestún & Ría Lagartos Biosphere Reserves
La Encrucijada Biosphere Reserve
El Triunfo Biosphere Reserve
Sian Ka'an Biosphere Reserve
El Ocote Biosphere Reserve

Calakmul Biosphere Reserve

Mexico Partner Organizations

The Nature Conservancy in Mexico