The San Pedro River has its origin in Mexico 10 miles south of the border and is one of only a few rivers that flow north from below the international boundary into the United States. The river lies six miles east of Sierra Vista.

Approximately 40 miles of the San Pedro from the border northward was designated as a national conservation area in 1988, primarily to protect the desert riparian ecosystem. Water isn’t the only thing that comes from south of the border. Birds, including grey hawks, are among the travelers.

“There’s something in the neighborhood of 100 species of breeding birds that use the San Pedro River and 250 or so migratory species,” says Robert Weissler, executive director of the nonprofit Friends of the San Pedro River. “And so we want to make sure that those populations continue into the future.”

The area also boasts a variety of flora, says Heather L. Swanson, Bureau of Land Management natural resource specialist.

“We have mixed grasslands, we have mesquite bosques, and then we have the cottonwood willow gallery, and all of those are very important for diversity of a variety of species," Swanson says.

More than 80 species of mammals, 40 reptilian and amphibious species and two native fish species also populate the region.