from the San Francisco Chronicle

The debate over the fence the United States is building along its southern border has focused largely on the project’s cost, feasibility and how well it will curb illegal immigration. But one of its most lasting impacts may well be on the animals and vegetation that make this politically fraught landscape their home.

Some wildlife researchers have grown so concerned about the consequences of bisecting hundreds of miles of rugged habitat that they have talked of engaging in civil disobedience to block the fence’s construction.

“This wall is so asinine, and so wrong; I am one of a dozen scientists ready to lay our bodies down in front of tractors,” Healy Hamilton, who directs the Center for Biodiversity Research and Information at the California Academy of Sciences, told colleagues at a recent scientific retreat in Tucson. “This is one thing we might be able to stop.” “Make it 13!” said Allison Jones, a conservation biologist at the Wild Utah Project, an advocacy group.

Fears for many species

Hamilton and Jones have yet to throw themselves before bulldozers, but their call to arms reflects the researchers’ growing fear that the wall will imperil species that, in Hamilton’s words, “walk, fly or crawl across that border.”

The scientists cite examples such as the 70 remaining Sonoran pronghorns in Arizona’s Cabeza Prieta National Wildlife Refuge, deerlike animals that are the fastest land mammals in North America. They are the only remaining population on U.S. soil, and the five surveillance towers that the administration plans to build in the area will be in the middle of the pronghorns’ range, producing noise and human activity that would disturb the sensitive species.

On April 4, Benjamin Tuggle, a regional director of the U.S. Fish and Wildlife Service, told customs and border protection officials that an interagency team of scientists concluded last month that the construction would inhibit breeding and, “over time, may ultimately lead to the eventual extinction of the species.” The Sonoran pronghorns are not alone: Rare species such as jaguars, ocelots and long-nose bats are also likely to face problems with the new barriers, scientists said.

However, the Bush administration recently waived more than 30 environmental and land-management laws to meet its deadline for building at least 360 miles of the border fence. Two advocacy groups, the Sierra Club and Defenders of Wildlife, have gone to court to challenge the constitutionality of the authority that Congress gave the administration to set aside federally required environmental reviews.

Amy Kudwa, spokeswoman for the Department of Homeland Security, said that despite the waivers, the agency has prepared draft environmental assessments or impact statements for much of the fence – which will be composed of metal, concrete or wire along different stretches – and that officials will continue to explore ways to mitigate its effect on vulnerable wildlife.

“Just because we’re using this waiver authority doesn’t mean we’ve not been mindful of our obligation to be stewards of the environment,” she said in an interview. “For a number of miles, we’ve determined that it would have only insignificant impact.”

Kudwa could not specify which areas would feel the greatest effects from the barrier, but she said Homeland Security is negotiating to give the Fish and Wildlife Service $800,000 to mitigate the wall’s impact on the Sonoran pronghorn and the long-nose bat in the Cabeza Prieta refuge, even though Homeland Security has waived its obligation to comply with Endangered Species Act requirements there.

Brian Segee, a Defenders of Wildlife staff lawyer, said the waiver decision will affect plants and animals in areas ranging from the Lower Rio Grande Valley National Wildlife Refuge in Texas to Arizona’s San Pedro Riparian National Conservation Area.

“We’re going forward blindly now, and we’re going to be learning about the consequences for years to come,” Segee said in an interview.

The legal and scientific battle over the fence – which will continue despite the administration’s waivers – highlights the reality that prized wildlife species are not respecters of international borders.

Diverse terrain

While popularly perceived as a barren desert, the landscape that straddles the border includes some of the world’s most diverse terrain, such as Arizona’s Sky Island area, which features isolated mountains surrounded by grassland or desert. Dotted with evergreen trees at higher altitudes, the region attracts jaguars as well as the Sonoran pronghorn and bighorn sheep that regularly crisscross between the United States and Mexico.

Farther to the east, the Lower Rio Grande Valley is home to one of the last free-flowing rivers in the United States, as well as more than 300 butterfly species, more than 500 bird species and the ocelot, an endangered wild cat. Even though 95 percent of the brush habitat in the four counties encompassing the Lower Rio Grande Valley refuge has been eroded, it still boasts 17 federally endangered or threatened species – more than the state of Louisiana.

“The significance of this area, biologically, is extraordinary,” said Evan Hirsche, president of the National Wildlife Refuge Association. He said the administration completed a draft environmental impact statement about the fence in three months, a process that would normally take two to three years.

Scientists are continuing to debate what will happen. A cadre of Mexican scientists is working with U.S. researchers to try to assess the populations that mix across the border even as fence construction is moving forward.

Rurik List, an associate researcher at the Institute of Ecology of the Universidad Nacional Autonoma de Mexico, said that aside from the Great Wall of China, “never before has something of this scale been constructed.

So nobody knows what will happen.”