U.S.-Mexico Border Wall: Wildlife To Bear The Brunt

The recent federal government shutdown, the longest in United States history, was a result of the ongoing feud between Donald Trump and Congress over funding for a border wall. On February 15th, Trump declared a national state of emergency as he demanded increased militarization of the border and further expansion of the border wall with Mexico. The border stretches 1954 miles (3,145 km) from the Gulf of Mexico in Texas to the Pacific Ocean in California. Trump plans to build a wall which spans the entire border. Construction of a new segment of the wall set to begin in February will cause significant damage in protected areas, including a section of the Lower Rio Grande Valley National Wildlife Refuge, as well as Bentsen-Rio Grande State Park and the National Butterfly Center.

Environmental protection has been disregarded in the name of national security. Trump persists that a militarized border will deter undocumented migrants and effectively reduce illegal immigration, as well as curb drug trafficking. He denounced illegal immigration from the southern border as “an invasion of our country.” Trump has fabricated a national emergency as there is no evidence of an imminent threat of “invasion.” In fact, the number of arrests of illegal border crossers is at a 45-year low. The wall is largely symbolic; it is a tool to further Trump’s xenophobic, anti-immigration discourse and is aimed at instigating racial hysteria for political gain. Critics argue that a barrier is likely to have little impact on illegal immigration while it costs taxpayers $18 billion and has ramifications for communities and wildlife populations along the border.

Less apparent are the ecological and environmental impacts of the border wall due to the lack of political and media attention. However, the effects are well known within the scientific community after a study published in BioScience last July was endorsed by over 2,900 scientists globally. The study found that a continuous wall threatens biodiversity and undermines binational conservation progress. The consensus within the scientific community is that construction of a border wall could cause an ecological disaster. In addition, the State of California and many environmental organizations, including Defenders of WildlifeEarthjustice, the Sierra Club firmly oppose the construction of the wall. They call upon politicians to consider the environment and wildlife when making decisions on national security.

Along existing fencing (700 miles [1,125 km] constructed during the George W. Bush administration), wildlife habitats have been eliminated, fragmented and degraded. This has reduced connectivity for plants and wildlife, impeding crucial water access and migratory routes of already endangered species. This has led to the isolation and decline of some rare species, including jaguars.

An expansion of the border wall will further threaten fragile, biologically diverse landscapes, including national parks and wildlife refuges. It is set to traverse six eco-regions, ranging from desert scrub, temperate forests, grasslands, freshwater wetlands and salt marshes. As a large-scale development project, construction of the wall and infrastructure, such as roads, lights and operating bases will likely degrade habitats causing geological issues, such as soil erosion and sedimentation, as well as destroy vegetation. Animal behaviour and movement will be disrupted, and populations will decline due to habitat loss and fragmentation, which reduces habitat connectivity. Furthermore, the wall will alter hydrological processes and water flow. The proposed wall will bisect the Rio Grande, the Tijuana and Colorado Rivers. Barriers could potentially act as dams and alter the natural flow of rivers, by blocking water access or exacerbating the risk of flooding. 

In regards to wildlife, analysis reveals that a continuous border wall would disconnect 1,506 native animals and plants from their geographic range. These include 62 “critically endangered” species, as listed by the International Union for Conservation of Nature (IUCN) Red List. Species include the Mexican grey wolf, Sonoran pronghorn and the ocelot and black bear both found within Texas’ Lower Rio Grande Valley. The wall will prevent wildlife from accessing food, water, mates and other resources. It will also disrupt wildlife corridors and migratory routes, which will alter annual or seasonal migration. Cutting off wildlife populations limits genetic diversity due to reduced gene flow and inbreeding, which furthers the risk of extinction. Conservationists are particularly concerned about the endangered Mexican grey wolf. In 2016, only 113 were recorded in the U.S. and about three dozen in Mexico. The wall will impede the movement across the border of wolves which help re-establish and grow populations in their range in the US. Wolves are a keystone species and are apex predators, meaning they play an important role in maintaining healthy, stable ecosystems. A barrier between their small, fragmented populations jeopardizes any chance of recovery.

The U.S. and Mexico have a long history of collaborative conservation on the borderlands. The border wall would devalue decades of coordinated conservation efforts and scientific research. Over the years, large swathes of land have been designated as protected areas (within 50 miles [80km] of the border lie 11 million acres of protected land) and millions of dollars invested to conserve biodiversity. Whereas, barrier construction will divert much-needed funding away from conservation projects.

Trump’s administration has failed to evaluate the environmental impacts associated with a border wall. The proposed barrier construction is exempt from 48 federal environmental laws, including the Endangered Species Act (ESA), National Environmental Policy Act (NEPA), the Clean Air Act and the Clean Water Act. Congress has the authority to waive environmental protection in the name of national security due to the enactment of the REAL ID Act in 2005. This grants the Department of Homeland Security (DHS) the authority to waive environmental laws that inhibit the wall’s construction. These waivers could dismiss decades of protective laws and compromise conservation efforts and scientific research.

To mitigate environmental harm, the U.S. Congress is urged to ensure the DHS implement and follow scientific frameworks and legal regulations, including the protection laws cited earlier. The government’s decision-making process should involve an in-depth environmental impact analysis. The government should also consider the development of less-damaging alternatives to border security, with barriers designed to maximize wildlife permeability. In addition, environmental monitoring should be carried out post-construction. A publication in Frontiers in Ecology and the Environment states that “Negative impacts could be lessened by limiting the extent of physical barriers and associated roads, designing barriers to permit animal passage and substituting less biologically harmful methods, such as electronic sensors, for physical barriers.” The scientific community urges the U.S. government to acknowledge and prioritize the conservation of the ecological, economic, political, and cultural value of the U.S.-Mexico borderlands. They demand that national security be pursued in a manner that preserves natural heritage. Protected borderlands are worthy of continued investment, rather than division and destruction.

Jenna Homewood