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Sian Ka'an Biosphere Reserve

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Sian Ka'an Biosphere Reserve

Located along the Caribbean coast in the State of Quintana Roo, Sian Ka’an was Mexico’s first Biosphere Reserve. As one of the largest protected areas in Mexico, it is an assembly of ecosystems, with equal parts lowland tropical forests, wetlands (marshes, flooded savannahs and mangrove forests), and coastal and marine habitats (lagoons, bays, and coral reefs).

did you know?

Sian Ka'an contains several unusual topographical features, including cenotes, (natural sinkholes) which often host wildlife endemic to a single cenote, and petenes, (hardwood hammocks) which support islands of rainforest among flooded savannah.

wetlands, Sian Ka'an

Wetland habitats stretch throughout Sian Ka'an
© Connie Gelb/TNC


site profile

total area protected:
1.5 million acres
map of site

Mexico Mangroves, Quintana Roo Wetlands, Yucatan Moist Forests, Central Caribbean Marine Region

partner organization:
Amigos de Sian Ka'an (ASK)

Ecological Importance

With nine vegetation types, Sian Ka’an is estimated to have over 1,200 species of vascular plants. Its wetlands are home to manatees and two species of endangered crocodiles, while the beaches are prime breeding areas for green, loggerhead, hawksbill, and leatherback sea turtles. The tropical forests provide habitat for several endangered and threatened species including jaguar, puma, ocelot, tapir, howler monkey, spider monkey, and king vulture. More than 330 species of birds are found here, including a large number of migratory songbirds.

The reserve’s boundaries extend to the Caribbean and encompass 68 miles of the Mesoamerican Reef, the second largest barrier reef in the world. Sian Ka’an’s mangrove and reef systems are some of the most productive in the world. Because of these unique values, Sian Ka’an was recognized as a UNESCO World Heritage Site and a Biosphere Reserve.


The explosion of tourism in Cancun from a sleepy fishing village to the largest resort destination in Mexico, has spread southward along the Quintana Roo coast, and poses several threats to Sian Ka’an. Unregulated tourism development, over fishing, forest fires, and uncontrolled resource extraction are some of the primary activities that threaten the reserve. Continued development along the coast has increased water pollution and altered the area’s hydrology, compromising the integrity of estuary, mangrove, and reef communities.

A Strategy of Success

When Parks in Peril (PiP) was initiated in 1991, Sian Ka’an had no on-site staff and an unclear understanding of local conservation needs. The goal of PiP at Sian Ka’an was to increase the protection of the reserve and install adequate infrastructure and long-term protection programs.

With PiP funding, partner organization Amigos de Sian Ka’an (ASK) had early successes in restricting zoning in and around the reserve and was able to mitigate the threat of increased tourism. ASK created “Kaanolopy,” a computerized GIS system used to track and manage development along the coast. ASK also conducted a study which determined the impacts of unregulated tourism and then established regulations for tourism development in the northern area of the reserve.

ASK conducted research that has been instrumental in securing the legal protection of over 2 million acres on the Caribbean coast, including Sian Ka’an. The organization also succeeded in gaining protected area status for the Arrecifes de Sian Ka’an, a coral reef system with an area of over 86,000 acres. In the marine area, the use of net fishing has been reduced by at least 95 percent and sport fishermen now use catch-and-release methods.

Upon site consolidation at Sian Ka’an in 1998, the reserve had adequate on-site staff and infrastructure; research and monitoring programs were in place and well as established community outreach and environmental education programs. PiP has also supported ASK as they have become Mexico’s leading authority on landscape-scale zoning, ecoregional planning, and coastal management.  With this recognition, ASK was invited by the government to permanently assist in addressing the threat of growing tourism development around Sian Ka’an.

Read more about Sian Ka'an...

Amigos de Sian Ka'an (ASK)
The Nature Conservancy in Sian Ka'an

Read more about projects in Mexico...

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

Calakmul Biosphere Reserve
Ría Celestun & Ría Lagartos Biosphere Reserves
Ajos Bavispe Biosphere Reserve
El Triunfo Biosphere Reserve
Loreto Bay/Isla Espíritu Santo Reserves
El Ocote Biosphere Reserve

La Encrucijada Biosphere Reserve

Mexico Partner Organizations

The Nature Conservancy in Mexico