The Environmental Cost of Development in a Biodiversity Hotspot

Global infrastructure development is reshaping tropical environments, yet its biodiversity consequences remain poorly quantified. We assess the ecological implications of Mexico's Interoceanic Corridor of the Isthmus of Tehuantepec (CIIT), a transcontinental megaproject linking transportation between the Atlantic and Pacific oceans across a global biodiversity hotspot. Despite its scale, no corridor-level environmental impact assessment exists, leaving major ecological risks unexamined. We estimate that several range-restricted species have more than 80% of their habitat overlapping the CIIT intervention area, with some likely to qualify as critically endangered or possibly extinct in the near future. Here, we reveal a critical governance gap and show that effective biodiversity conservation strategies are mandatory to preserve endemic biodiversity impacted by infrastructure development. We recommend the creation of an independent, multi-stakeholder task force to ensure compliance with environmental standards to increase transparency for reporting on environmental impacts, as well as targeted interventions to reduce negative impacts on biodiversity through the implementation of habitat and species safeguards. Addressing this is essential to align infrastructure development with national and global sustainability commitments.