The Isthmus of Tehuantepec is a broad, plateau-like ridge that separates the Bay of Campeche (located in the Gulf of Mexico in the north from the the Gulf of Tehuantepec (part of the South Pacific Ocean). The isthmus has a width of 220 kilometers at its narrowest part between the two gulfs. The southeastern parts of the Mexican states of Veracruz and Oaxaca occupy territory in the isthmus, while the Mexican states of Chiapas and Tabasco lie to its east. The Isthmus of Tehuantepec lies just to the west of the Yucatan Peninsula, where many consider Central America to be geographically separated from North America.
Before the construction of the Panama Canal, the Isthmus of Tehuantepec was regarded as a potential site for construction of a canal that would connect the Atlantic to the Pacific. Since the days of the Spanish Conquistador Hernán Cortés in the early 16th Century, thoughts of constructing a canal across the isthmus were being considered. However, the realization of the difficulty to create a canal along the broad isthmus soon led to a shift in attention to the narrower Isthmus of Panama where the Panama Canal was indeed constructed, and then opened in 1914. In 1853, as per the Gadsden Purchase Treaty, the Isthmus of Tehuantepec was extensively used by the United States to transport mail and trade goods between the Gulf of Mexico and the Pacific. In the later years, the Mexican Government signed several contracts with contractors to start building an extensive railway system across the isthmus to connect the ports at either end of the land. Currently, this railway system and sea ports on both sides work in coordination with one another to facilitate the transport of goods and passengers across the isthmus.
The Isthmus of Tehuantepec houses some of the richest tropical forests of the world, with a high biodiversity of species therein. A significant portion of the Mexican population, including native communities primarily comprised of the indigenous Zapotec peoples, also inhabits this region. The women of this region, known as “Tehuanas", are famous for their confident personalities and able skills in trading. The isthmus also hosts a number of lagoons along its western, Pacific coast, and these have enormous potential for commercially lucrative fishing. Oil and petroleum reserves and some other mineral reserves have also been located in the isthmus, though they have yet to be exploited to an extensive degree.
Habitat and Biodiversity
The Isthmus of Tehuantepec experiences a hot and humid tropical climate. Average annual rainfall on the Atlantic (Gulf of Mexico) side of the isthmus in the east is around 3,960 millimeters, while the Pacific shores of Tehuantepec have a drier climate. The isthmus hosts the Selva Zoque, one of the most ecologically significant areas in Mexico, an a region hosting the greatest diversity of terrestrial species in the country. Around 3,500 species of vascular plants, including 300 orchid species and other valuable plant species like palmita, big-leaf mahogany, and tropical red cedar, are found in these forests. A great diversity of animals, including spider monkeys, jaguars, White-lipped peccaries, and over 600 species of birds, including the Harpy eagle, Grat curassow, and Ornate hawk-eagles, also inhabit the forests of the isthmus.
Environmental Threats and Territorial Disputes
Since the Isthmus of Tehuantepec was one of the least explored and exploited parts of Mexico up until now, preserving its native habitat was not a big issue. Currently, however, upcoming developmental projects in the region could threaten the future of the isthmus’s ecosystems. The Trans-Isthmus Project plans to build large scale petroleum facilities, shrimp farms, industrial parks, and mono-cropped tree plantations throughout the region. The indigenous inhabitants of the region, dependent on the natural resources of the isthmus for their livelihoods, are complaining that the project would lead to the loss of important mangroves, palm groves, and the traditional economic means associated with them. The future of the Isthmus of Tehuantepec thus depends on how well the government manages the developmental activities of the region while maintaining the balance of its biodiverse ecosystems.