Originally Published in CNN
Ed Lavandera and Ashley Killough - December 23, 2020
The river's winding path is a migration gateway and critical habitation for hundreds of animal species. The National Audubon Society for Arizona
says 40% of bird species in North America spend part of their lives on the San Pedro River at some point.
But the US Border Patrol sees the river as a natural gateway of drug smuggling and illegal immigration into the United States.
In the waning days of the Trump administration, construction crews are rapidly building a 30-foot high steel bollard-style wall across the riverbed. Usually, the only sound you hear is the wind whipping through the golden leaves overhead. As you hike toward the spot these days, the clattering sound of construction crews takes over.
Environmentalists say the work disrupts the migration patterns that rely on the river.
Customs and Border Protection says border wall projects have gone through "Environmental Stewardship Plans" to analyze and minimize the environmental impact in the area where construction is happening. And that part of the environmental impact analysis includes studying how wildlife may be affected by the projects.
The work is part of a final sprint to complete as many miles of border wall as possible before President-elect Joe Biden takes office on January 20.
As of December 18, construction crews had completed 438 miles of border wall since January 2017, according to Customs and Border Protection. Last year, the Trump administration vowed to complete 450 miles by the end of 2020, just over a week from now. There are 37 border wall construction projects in motion along various points of the border with Mexico, according to the US Army Corps of Engineers.