The Huatulco National Park and Biosphere Reserve is located in the physiographic province of the Sierra Madre del Sur, characterized by bays, cliffs and rocky escarpments.
The Huatulco National Park was founded in 1998, protecting 5,516 ha (13,630 acres) of marine territory and 6,375 ha (15,752 acres) of land which are officially set aside to be left undeveloped. In 2006 this area was listed as a UNESCO Biosphere Reserve. It is located in the Municipality of Santa María Huatulco.
The site presents rocky associations of various ages that make up the texture of the land in Huatulco. The relief of the biosphere reserve is mountainous in its southern portion, with valleys perpendicular to the coast. The terrestrial part is composed of rounded hills, isolated hills, dunes, escarpments, cliffs, mangroves, wetlands, savannah, lowland deciduous and riparian vegetation. In the marine part can be found bays, beaches, islands, kelp and coral communities.
In the lowlands of the park, there are 9,000 species of plants (about 50% of the species are reported throughout the country) in the forest and mangroves in the coastal belt. Vegetation is dominated by the low forest growth of caducifolia in 80% of the area with the unusual feature of 50 ft (15 m) high trees.
Fauna species have been identified as 264, which includes armadillos and white-tailed deer. There are approximately 700 counted bird species which include hummingbirds, pelicans and hawks. The reptile species are counted to be 470, which include Black Iguana, salamanders and snakes. Dolphins, whales and turtles are sighted species off the coastline, out of the identified 100 amphibian species.