U.S.-Mexico Border Wall

A Wall Has No Place in the Sky Islands

The wall being constructed at the U.S.-Mexico border has cut through the heart of the Sky Islands, causing enormous environmental destruction — endangering springs, damaging waterways like the San Pedro River, and stopping wildlife in their tracks. It’s also harming public lands, Indigenous lands and culture, local communities, human rights, and civil liberties.  

This goes against everything we stand for at Sky Island Alliance, with our mission to protect and connect the region’s landscapes, people, and wildlife for the benefit of all. Read on to learn more about what we’re doing to protect our borderlands from this threat.


Advocacy | Habitat Recovery | Research | Tour the Border


Here’s what we’re doing to protect our Sky Islands from the border wall: 

  1. Studying borderlands wildlife and ecosystems and sharing that vital information with the public and policymakers; 
  2. Advocating for new border policies to reinstate laws and stop wall building; and 
  3. Working to restore wildlife pathways and waterways across the border.  

Explore this page to learn more about the U.S.-Mexico border wall, law waivers that have enabled its construction, local impacts, and how you can join our crucial work. 

Photo by Frank Staub/Lighthawk.


The federal government has been developing U.S.-Mexico border wall infrastructure since the early 1990s. In 2005 Congress passed the Real ID Act, which allows the Department of Homeland Security to waive any local, state, or federal laws to build border infrastructure. To date at least 84 environmental laws have been ignored — along with other laws and statutes, including ones protecting Native cultural resources. 

On Jan. 20, 2021, after years of accelerating wall construction under the Trump administration, President Biden issued a proclamation pausing all activity until funding and contracts were reviewed — but some wall construction has continued in Texas. 

The Biden administration returned funds to the Department of Defense that had been illegally diverted to build border wall in Arizona. Despite the incredible need for restoration at the border, no money for it has been approved by Congress, and the details of U.S. Customs and Border Protection’s pending remediation plan remain unclear. While long-term habitat restoration at the border isn’t yet happening, Homeland Security has authorized CBP to begin short-term remediation projects in Arizona. The situation is ongoing and still developing. 

Latest News 

July 11, 2022: The Department of Homeland Security published an update on its border remediation plan. Unfortunately there was no honest accounting of the severe damage the wall continues to cause or the urgent need for restoration of surrounding lands. Instead the agency has decided to use money from 2020 to continue funding stadium lights, cameras, and detection technology in areas where physical barriers were previously constructed. This puts approximately 455 miles of the southwestern border at severe risk of light pollution and poses a major threat to migratory birds and other wildlife. In Arizona alone this plan will affect such treasured areas as Organ Pipe Cactus National Monument, San Bernardino National Wildlife Refuge, Guadalupe Canyon, San Pedro Riparian National Conservation Area, and Cabeza Prieta National Wildlife Refuge. The agency also noted that, “due to higher-than-expected remediation costs,” it will end the environmental planning process in Texas’ Laredo Sector.

May 10, 2022: Along with 103 diverse organizations, Sky Island Alliance signed a letter to Congress, urging it to oppose border wall funding in its Department of Homeland Security appropriations for FY2023. We specifically asked that any existing border wall funds be rescinded and that money set aside in the future be used to begin the process of healing the borderlands. Local communities and wildlife have suffered from careless border wall construction, and it’s up to Congress to rectify this mistake.

Read our full list of border wall updates here.

    April 6, 2022: CBP provided some info about its Border Barrier Remediation Plan for Tucson Sector via webinar on April 4, 2022. Much remains unshared with the public. However agency representatives confirmed that 25 gaps in the wall in southeast Arizona will be closed. While locations weren’t specified, they did say wall closures would occur only in small gaps (<150 feet in width) where planned gates weren’t completed during the last phase of construction. This means that the Santa Cruz River isn’t one of these gaps and should remain unwalled under the current plan. The remediation work will be paid for with congressional funds from 2020. CBP is reaching out to constructors to solicit bids now (via requests that aren’t yet public), and construction work is likely to begin in a few months.   

    March 30, 2022: CBP is hosting a webinar on April 4, 2022, at 6 p.m. PT to provide an update on how feedback will be incorporated into the first remediation contracts for the Tucson sector. The webinar is open to the public. To register, send an email with your name and affiliation to TucsonComments@cbp.dhs.gov with the subject “Tucson Remediation Plan Webinar.” Login info will also be posted on this page the day of the webinar. 

    March 24, 2022: Customs and Border Protection shared a summary of stakeholder feedback received on the Border Barrier Remediation Plan for Tucson Sector. 810 comments were received and overwhelmingly expressed concern over the long-term harms the border wall and remediation plan would have on native plants, wildlife, and habitat.  

    March 9, 2022: In a major blow to stopping border wall construction, today the U.S. House Appropriations Committee introduced new legislation that does not rescind existing border wall funding from 2018/2019 and does not include border-mitigation funding. While this doesn’t necessarily mean that more border wall will be built this year, the risk of new wall construction remains very high because Homeland Security retains the authority to rescind federal laws and statutes at the border. The existing law waivers must be repealed immediately to protect life and land in the borderlands. 

    Levee repairs are underway the week of Feb. 28, 2022 in Texas that include the installation of border wall segments on the western edge of the National Butterfly Center in the Lower Rio Grande Valley Wildlife Conservation Corridor. Attacks by political extremist groups have forced the temporary closure of the National Butterfly Center, a conservation organization standing up for human rights and wildlife protection in Texas. We stand in solidarity with the people and communities under direct threat by continued border wall construction. Photo by Marianna Wright/National Butterfly Center.

    March 8, 2022: New wall is under construction in Texas, as “levee repairs” are underway along the Rio Grande River today that include the installation of steel-bollard border wall. CBP has also requested public comment on their proposal to build 86 miles of new wall in Texas along the Lower Rio Grande Valley. Funding for this construction will come from congressional appropriations from 2018 and 2019. If this wall is built, both the human and wildlife communities will suffer along the Rio Grande River, where the wall will block natural floodplains in Starr and Hidalgo counties and pose devastating flood risks. Because the congressional funding for the border wall and waiving of at least 84 different federal laws and statutes continued under the Biden administration, this new wall construction is likely. This wall will greatly increase the likelihood of ocelot extirpation in Texas, as their habitat will be severely fragmented. Sky Island Alliance cosigned a letter of opposition for this wall construction proposal with more than 30 other conservation, human rights, and borderland groups. 

    Feb. 3, 2022: The feedback period for CBP’s Border Barrier Remediation Plan closed. For more details on what it entailed and the input we submitted, visit our Action Alert page. 

    Jan. 4, 2022: CBP released a new Border Barrier Remediation Plan for the Tucson sector (Pima, Cochise, and Santa Cruz counties). Proposed actions in the plan include closing gaps in the border wall. CBP requests the public to submit feedback on the plan by Feb. 3, 2022. 

    Dec. 20, 2021: Homeland Security gave CBP the green light to complete projects along the U.S.-Mexico border that are necessary to “address life, safety, environmental, and other remediation requirements” in the Tucson, Yuma, El Paso, and Del Rio sectors. (Permission to complete these projects in the El Centro, Rio Grande Valley, and San Diego sectors was also given to CBP in July 2021.) These projects appear to be funded. 

    Oct. 8, 2021: Homeland Security announced the cancellation of border barrier contracts located in CBP’s Laredo and Rio Grande Valley sectors. 

    July 2021: The House version of the Homeland Security appropriations bill directed $75 million from DHS to the U.S. Fish and Wildlife Service for mitigation activities around the border wall and barriers. We’re hopeful these funds will be used to start restoration projects in 2022. 

    April 30, 2021: The Department of Defense announced it would cancel all contracts and border barrier projects that were paid for by funds taken from reserve originally intended for military use. This included Arizona’s open projects. 

    Feb. 23, 2021: Sky Island Alliance and 70 other groups sent a document titled Stopping the Border Wall: Criteria and Priority Areas for Conservation and Restoration to the White House. The document called for the Biden administration to cancel border wall contracts, restore lands damaged by construction, remove sections of built wall, and restore equal protection under the law along the U.S-Mexico border. 

    Jan. 20, 2021: The Biden administration issued a proclamation that paused all border barrier construction until the wall’s contracts and funding sources could be reviewed. 


    How the Wall Harms the Sky Islands 

    At least 84 federal and state laws and regulations, including the Endangered Species Act and the National Environmental Protection Act, were waived to advance border wall construction in California, Arizona, New Mexico, and Texas.  

    Oak trees bulldozed near the border to make room for construction equipment.

    Here are just a few ways the wall is doing specific harm: 

    • It has reduced the number of wildlife migration corridors, separating animals from food, habitat, and their core populations in the U.S. and Mexico. The wall especially hurts large mammals, low-flying birds, and endangered species like jaguars, ocelots, and Mexican gray wolves. 
    • At least 60 new roads were graded for border patrol and for access to construction sites. In the process a lot of water was wasted to keep dust down. Cacti, trees, and other plants were bulldozed and removed. And vehicle traffic created noise and light pollution that disturbed wildlife. 
    • Water was pumped from underground aquifers and springs to mix with concrete for the wall, and sections were built across waterways like the San Pedro River, which dammed certain places or reduced flow. This harm to our rivers and aquifers is especially devastating during times of drought. 
    • New border lighting disrupted nocturnal species that rely on the cover of darkness to travel and hunt. Through our Border Wildlife Study, we’ve found that a majority of all mammal sightings occurred between sunset and sunrise, and half of the mammal species we’ve photographed have only been seen at night. 
    • Indigenous communities and Tribal lands have been harmed by the border wall. Barrier construction has disturbed or destroyed graves and cultural sites and infringes on Native sovereignty. Sacred lands and springs were torn apart by road grading and wall construction without meaningful consultation. Learn more about why the Tohono O’odham Nation opposes the wall. 

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