Trump administration to build border wall across wildlife corridor at San Rafael Valley

• The Trump administration plans to build nearly 25 miles of steel-posted border wall through Arizona's San Rafael Valley.
• The San Rafael Valley is considered part of a critical wildlife migration route, especially for endangered species like the jaguar and ocelot. Existing barriers allow the animals to pass through.
• Environmental groups oppose extending the wall through the San Rafael Valley, but challenging it will be difficult because laws allow the government to waive environmental regulations.

The Trump administration intends to build 24.7 miles of border wall across the southern San Rafael Valley, a remote area south of Sonoita, Arizona, that is a vital migration corridor for jaguars and other wildlife, officials have confirmed.

The Sierra Club received word of the move in one of the monthly updates on border construction activities it receives from the government. The updates are part of a settlement from the 2019 lawsuit it filed against the previous Trump administration, which had declared a national emergency allowing it to redirect funds toward wall construction.

Officials with the Homeland Security and Justice departments confirmed in writing on April 11 that the valley, which is bounded by a line of vehicle barriers, will now be targeted for construction of a pedestrian-blocking steel wall, said Erick Meza, borderlands coordinator for the Sierra Club.

U.S. Customs and Border Protection confirmed the San Rafael Valley plan to The Arizona Republic on April 14.

“I was hoping that San Rafael Valley was not going to be part of this,” Meza said, “that there was not going to be enough money to do it.”

Homeland Security officials said they have a $500 million fund left over from the previous emergency declaration, Meza said.

The San Rafael is one of two stretches of border where former Arizona Gov. Doug Ducey hired contractors who began erecting barriers by stacking shipping containers in 2022. Environmentalists protested the resulting makeshift wall extending west from Coronado National Memorial.

Ultimately, facing federal legal action from the Biden administration, the governor backed down and agreed to remove the containers.

Valley is a connection to jaguar, ocelot populations

The valley spans from the gap between the Huachuca Mountains in Cochise County on the east and the Patagonia Mountains in Santa Cruz County on the west. It is farther from Mexico’s Highway 2 than other border stretches that the government previously walled off, and it is thought to be the corridor that the most recently sighted jaguar in the U.S. traversed en route to the Huachucas.

It is also some 30 miles north of a small ocelot population, and a solo ocelot that may have come from there has roamed the Huachucas in recent years.

Neither cat species is known to have a breeding population north of the border, as all individuals confirmed since the 1990s have been males.

“If we’re ever going to see jaguars in Arizona, that place needs to have wildlife corridors open,” Meza said.

On Friday, President Donald Trump signed a national security memorandum authorizing the U.S. military to operate within and along the Roosevelt Reservation, a narrow band of federal land along the border typically patrolled by border agents. The move could massively increase activities in the region aimed at deterring or detaining unauthorized border crossers.

“Our southern border is under attack from a variety of threats,” Trump said in his memo. “The complexity of the current situation requires that our military take a more direct role in securing our southern border than in the recent past.”

'This isn't border security, It's ecocide'

Borderlands environmental groups have generally argued that the president’s fixation on a wall is misguided, and say surveillance technology already on the ground, in the air and on Border Patrol vehicles is a more efficient deterrent to border crossers in remote zones like the San Rafael. They consider chest-high vehicle barriers — horizontal steel rails welded onto X-shaped supports — sufficient to block major human incursions while allowing jaguars, bears, deer and other animals to move freely.

"Trump is poised to rip a 25-mile border wall as high as a three-story building through some of the last remaining wild places in Arizona's borderlands,” Russ McSpadden of the Center for Biological Diversity said in an email statement. "It'll sever a vital corridor for endangered jaguars and ocelots. This isn't border security, it's ecocide." 

The Sierra Club will consider its options in opposing a wall across the San Rafael, Meza said, though a Patriot Act exemption of environmental and Endangered Species Act rules on the border has made stopping construction difficult in the past.

“Ideally we wouldn’t have a wall, and we’re going to try to continue to figure out a legal way to slow them down or stop them,” Meza said. “At minimum, (we’ll) try to make sure small and large openings would be involved.”

Openings just 8 ½ inches by 11 inches at the base of other wall segments have been found to allow animals as large as coyotes and mountain lions to pass, though not bears and likely not jaguars. In other places, such as the San Bernardino National Wildlife Refuge in southeast Arizona, the government has agreed to keep flood gates open and under close observation, leaving a few places where larger animals can pass.

So far, Meza said, the government has not confirmed any plans to wall off two other sensitive stretches of border: the Pajarito Mountains west of Nogales or the Tohono O’odham Indian Reservation.

Brandon Loomis covers environmental and climate issues for The Arizona Republic and azcentral.com. Reach him at brandon.loomis@arizonarepublic.com.

Environmental coverage on azcentral.com and in The Arizona Republic is supported by a grant from the Nina Mason Pulliam Charitable Trust.

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