Mexico's Maya Train and the dangers of habitat fragmentation

I cannot, in good faith, offer an informed opinion on the magnitude and severity of the environmental, cultural, and social impacts that may be expected from the construction of the ambitious, government-sponsored touristic undertaking known as “ The Maya Train ” in southern Mexico . Simply because precise information on the project has not yet been released and, above all, no environmental or social impact assessments have been conducted—even though both are required by Mexican law.

Here’s what little has been made public: construction of the train is planned to begin in late 2019 and be finished by 2022 , the railway tracks would run over one thousand miles, and the project’s total investment would be about 6 to 8 billion dollars ( Mexico's Institute for Competitiveness, a think-tank, estimated that without proper planning the cost might actually be 4 to 10 times more than that ). The train is intended to boost the tourism industry in many of the most culturally and biologically diverse, and sensitive areas in Mexico across the states of Chiapas , Campeche , Quintana Roo , and Yucatán .

The amazing Maya archaeological sites like Palenque , Calakmul , Tulum , Xelha , and Coba , as well as Chichén Itzá , Huxmal , and Izamal —many of which are registered as UNESCO Cultural Heritage sites —are on the train's planned route, with the hopes of attracting high numbers of tourists from Mexico and abroad. Likewise, this region is home to some of world's most biologically-diverse protected areas, including UNESCO Natural Heritage sites and biosphere reserves that provide safe heavens to a host of endemic and endangered species, such as Sian Ka´an and the mixed cultural/ natural site of Calakmul and its Ancient Maya City and protected forest, the largest chunk of tropical forest protected in Mexico today.

Despite the lack of public information about the project, what I can offer are some thoughts on the looming environmental impacts the project might cause. There are numerous experiences from around the world (including Mexico) that illustrate the impacts of habitat destruction and fragmentation from activities such as deforestation and urban and tourism development. It is worth examining some of the lessons learned.

Fragmentation

is the process whereby a large, continuous area of habitat is reduced and broken up into smaller pieces. This results in a mosaic of two or more isolated patches. Building barriers is what fragments habitats and reduces the ability of individuals of a species to move and find food, mates, migrate, and settle in new territories. Such barriers can be roads, railways, canals, various kinds of fences or walls, pipelines, or any obstacle that hinders the free movements of individuals, including umbrella species such as jaguars that, if protected, also brings protection for many other species that share their habitat. Fragmentation results in smaller pieces of land that, while they still may be “protected” (on paper), are in fact small islands of the original habitat, each surrounded by an inhospitable territory dominated by humans.

Habitat fragmentation

can precipitate the decline and extinction of once-broadly distributed animal populations by splitting them into two or more subpopulations, each located in a restricted area and with a reduced number of mating partners. It also aggravates the “edge effect”—the degraded environmental and biological conditions at the edges of a habitat. Fragmentation severely increases the edge effect, as it divides a previously larger population into smaller ones that are more prone to extinction. The vulnerability of those areas to invasive species and disease epidemics also increases.

For example, more wind, lower humidity, and higher temperatures at the edge of a forest increase the possibility of wildfires. Fires can spread to fragmented habitats from nearby human settlements, from agricultural lands, or from farmers using badly-planned crop rotation. Accidental wildfires can also increase due to vehicular traffic, careless tourists, or local inhabitants. There are many examples around the world, including from Mexico , in which millions of hectares of tropical forest, and the animals therein, were devastated by fires caused by humans, frequently during droughts. Fragmentation of tropical forests and wildfires caused by people greatly exacerbate environmental, economic, and social catastrophes.

Simply a wall, or another human-made barrier , can threaten the very existence of species and populations. Many species of reptiles, amphibians, mammals, and birds that inhabit tropical forests are unable to cross even small tracks through an open area, because of the dangers of being eaten or because they avoid too sunny, hot, noisy, or dry environments. Animals crossing roads are also frequently hit and killed by automobiles. Moreover, when habitat fragmentation reduces animal movements, plants with fleshy fruits or sticky seeds that depend on animals for dispersal are unable to do so, and the fragmented habitats can lose the native plant species that would otherwise settle there.

Habitat fragmentation

caused by roads and other entry points may also attract legal and illegal hunters, who take advantage of the situation to exploit newly-available remote areas. Without proper regulations and enforcement, there will be no safe havens for animals, and their populations will inexorably dwindle. Finally, habitat fragmentation also places wild populations closer to domestic animals, increasing the chances that diseases pass into wild species, and vice versa. Once the level of transmission is augmented, the odds of spreading contagious diseases to domestic animals, plants, and people increase.

Development and preserving nature are not mutually exclusive. Both can, and must, coexist if we humans and the natural world are to survive. Well-informed planning, respect to indigenous peoples, ample involvement of society, transparency, the rule of law, and accountability are essential for people to thrive and live in harmony with nature .