In the South of the Mexican state of Veracruz, between the Gulf of Mexico and the coastal plain, there is a small volcanic mountain ridge, the Sierra de Los Tuxtlas. It is made up of volcanoes reaching up to an altitude of 1700 metres (5577 feet). The mountains present a barrier for clouds coming from the Gulf of Mexico, causing the windward parts of the mountains to receive up to 4500mm (18in US) of precipitation per year, making it one of the most humid zones in Mexico. These geological and climatic factors are the cause of a wide variety of ecosystems (for instance: coastal dunes, mangroves, cloud forests, tropical rainforests) and of flora and fauna. More than 3000 species of plants have been found in the region, as well as more than 850 species of vertebrates, making up one third of all the species of Mexico. Many of these species are in danger of extinction. Some are endemic to this region alone, like the Tuxtla Quail Dove (Geotrygon carrikeri) and the Longtailed Sabrewing hummingbird (Campylopterus excellens).
Since the times of the Olmec civilization (1400-400 BC), humans have settled in Los Tuxtlas. The pre-hispanic use of land allowed the rainforest to regenerate itself regularly and did not negatively affect the biodiversity. The indigenous people were highly dependent on the rainforest, which provided them with about 200 edible plants and even more medicinal plants. Apart from that, the forests of the region provide many important environmental services, such as regulation of local climate and of hydrology, impeding inundations and soil erosion in the rainy season, and guarding water for the dry season. Today, the rainforests of Los Tuxtlas also have a great importance on a global scale: they capture carbon dioxide, thereby diminishing climate change.
In the 20th century, however, a new model of cattle ranching was promoted which brought about the destruction of the majority of the rainforest. Between 1972 and 1992, half of the forest cover rapidly disappeared. In 1998, parts of Los Tuxtlas were declared as a Biosphere Reserve. Since then, destruction of nature in the region has diminished, but it hasn’t stopped completely. Today less than 20 % of the region is covered with forests. Nevertheless, Los Tuxtlas still contains one of the most important oases of tropical rainforest in Mexico.