The Trump border wall is proving a disaster for at-risk animal species

In southeastern Arizona, it is already oppressively hot early in the morning. The thermometer rises to 38 degrees Celsius (100 degrees Fahrenheit) during the day. The soil looks parched, yet various types of cactus grow here, along with shrubs and trees. The Sonoran Desert, which stretches across several states in the U.S. and Mexico, is a protected landscape. The desert is also home to a number of animals. But even from a distance, a steel structure is visible that runs through this unique area like a scar. This is part of the famous wall, the «Trump wall» that stretches along 113 kilometers (70 miles) here and closes the border to the county’s southern neighbor Mexico.

Joe Biden recently announced the construction of another 20 miles of wall in Texas. The U.S. president has said he does not consider the project to be sensible. But the funds were allocated in 2019, and cannot be used for anything other than building the wall in Texas. Like here in Arizona, the fence is intended to prevent migrants from entering the U.S. illegally. But in all places along the border, the fence has a completely different effect – it cuts through animal habitats, and threatens the survival of endangered species.

On a Monday morning at the end of September, we are standing right next to the border fence in the Sonoran Desert. «If a bear were standing in this spot, it would have to hike eight miles east or 62 miles west to find an opening. It might manage eight miles, but 62 miles is not feasible for him,» says Eamon Harrity. The biologist works for the Sky Island Alliance, an organization that documents the environmental problems here in the border region. Since 2020, with an increase in pace since 2022, it has been collecting data on the movements of various animals along the fence using more than 100 wildlife cameras.

Only 11 openings for animals over 113 kilometers

The Sonoran Desert is rich in biodiversity. Protected animals such as jaguars, pronghorn antelopes and Mexican wolves live here, but many other mammals can also be found, including black bears, lynx and mountain lions. A simple rule applies to all these animals: In order to find water and food in the barren landscape, they have to wander, often across long distances. The larger the area they can roam, the better the chance of finding these vital resources.

The wall has been a virtually insurmountable obstacle in their habitat since 2020. Along the 113 kilometers of this section of wall in Arizona, just 11 openings for animals have been made, all the size of a sheet of notebook paper. The results of this planning can be seen in the tens of thousands of pictures and videos that the Sky Island Alliance has taken in recent years. While some smaller animals manage to crawl through one of the openings, many others run unsuccessfully alongside the steel pillars. Bears, deer, mountain lions and jaguars have no chance of getting to the other side.

The consequences for the animals are clear, as environmentalists point out. «If you cut the area in half, you also cut their chances of survival,» says Erick Meza, who works as borderlands coordinator for the nature conservation organization Sierra Club in Tucson, a good 240 kilometers from the San Bernardino Valley.

The fragmentation of habitat is not only a problem for foraging, Meza notes. It also has an effect on the animals’ reproduction. «In the separated habitats, the selection of potential partners is smaller,» Meza says. Species such as wolves and jaguars in particular, which tend to be solitary, are thus likely to find it increasingly difficult to produce offspring.

Fear of terrorism trumps environment

Conservationists had feared early on that the wall would have consequences for the environment. When the fence was erected in 2018, organizations such as the Sierra Club immediately initiated legal proceedings. They complained that the construction, which took place partly in nature reserves, violated various environmental and species protection laws.

But these objections had little chance, as the Trump administration indicated that the fence was offering protection from terrorists. In 2005, following the attacks of Sept. 11, 2001, policymakers decided that existing laws could be set aside if national security issues so required. According to Trump, there was a risk of terrorists entering the U.S. via the border with Mexico.

As a result, the courts have dismissed all lawsuits filed by environmentalists against the wall project. A total of 48 federal laws were ignored for the construction, including laws to protect water and air quality and regulations protecting Native Americans. Something similar is now happening under President Biden. In order to allow the wall to continue to be built in Texas, 26 nature and environmental protection laws were waived in October, including the Endangered Species Act that protects at-risk species.

«There weren’t even any environmental impact assessments performed,» says the Sky Island Alliance’s Harrity, looking back on the construction in Arizona. The only concession, according to Harrity, were the 11 notebook-paper-sized openings, too small for larger animals, that were welded into the steel girders.

Hilltops blasted away

However, the division of their habitat is only one of several problems that the wall’s construction created for the animals. The entire region has changed as a result of the construction work. The border fence south of Tucson stretches in a perfectly straight line. Entire hilltops were blasted away to make way for it. Builders also created the infrastructure needed to bring heavy construction equipment into the border region, running it through a previously largely untouched landscape. A two-lane road now parallels the wall, today used mainly by Border Patrol officers cruising in their SUVs.

«The animals in the area now have not only a physical barrier, but also a human barrier of vehicles, noise and light,» says Harrity. To make the Border Patrol’s work easier, large sections of the wall are brightly lit. Harrity notes that this may particularly affect the many migratory birds that fly past at night, trying to orient themselves by the starry sky. Although the effects have not yet been studied, the Sierra Club’s Meza says he is certain that the «stadium floodlights,» as he calls them, «disturb the behavior of wild animals.»

In addition to visible changes, the construction of the wall has also created problems that reach deep into the earth’s interior. «The water used for the concrete mix for the fence foundation was pumped from the few natural springs. These held water that had been stored there since the ice age,» says Elizabeth Wilder, a professor at the School of Geography, Development and Environment at the University of Arizona in Tucson.

More than 400,000 liters of crystal-clear drinking water were pumped out with each tanker load. As a result of this massive use, the groundwater level here has fallen. Where water previously came to the surface naturally in small ponds, solar pumps now have to be used to preserve the few wetlands in the region. This is not a good development with regard to the animals’ search for water.

The various problems add up to a «catastrophe for the animal world,» as Wilder puts it. For endangered species in particular, such as the jaguar or the Mexican wolf – only a few dozen of which live on each side of the border – Wilder’s prognosis is not good. «If we don’t take action, it won’t be decades before these animals disappear,» she says.

Action? Even to environmentalists, it is clear that the wall will not be pulled down. Their demand therefore seems rather modest: They want new and larger openings to be cut into the fence, so that more animals can cross the artificial border. However, the question of whether the current holes will be enlarged is ultimately up to the local Border Patrol. To convince them, the environmentalists are keeping their cameras rolling – image by image, they want to draw attention to the animals’ dangerous impasse.

The reporting for this article was supported by Riff freie Medien GmbH.

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