TUMACÁCORI, Ariz. — The Santa Cruz River is not like most American rivers. If some of its admirers get their wish, it might also become a wildlife refuge unlike any other. Much of its 184-mile length ...

Pick a sunny day. Drive down Mule Pass just outside of Bisbee. Go through the tunnel. Find the trail that starts under a tree. Trek up Mount Ballard 7,000 feet, and look carefully. There, in the ...

Surrounding Rodrigo Sierra Corona in the foothills between the Santa Rita and Patagonia mountain ranges—two of Arizona’s famed Sky Islands that support isolated, high-elevation habitats—were dry ...

A genetically distinct population of Yarrow's spiny lizard in Arizona's Mule Mountains is facing local extinction due to climate change. Conservationists have petitioned to list the lizard as a ...