A tiny endangered springsnail found only along Arizona’s border is at the center of a new lawsuit.

A wetlands restoration project in eastern Arizona, which has bolstered six ponds, is helping a frog species get through ...

"There's potential that whatever turtles we salvage from Quitobaquito may not be able to go back there for a long time." ...

ORACLE, AZ — Four dozen Sonoyta pupfish are now swimming beneath the towering glass pyramids of the University of Arizona’s Biosphere 2 after a multi-year effort to conserve the critically endangered ...

A Tucson-based environmental group is accusing the Trump administration of moving at a snail's pace in determining whether a ...

State and federal bills removing Mexican gray wolves from the endangered species list could harm both the animal and ranchers ...

Cinco, the endangered jaguar, is still roaming Arizona's Sky Islands, and the proof is on a trail video camera.

Wildlife officials are planning an emergency rescue for an endangered species that could see its only U.S. habitat wiped out ...

The spots gave it away. Just like a human fingerprint, the rosette pattern on each jaguar is unique so researchers knew they had a new animal on their hands after reviewing images captured by a remote ...

The rare Sonoyta pupfish were introduced into a desert river habitat inside the huge Biosphere 2 structure near Tucson. The dish are native to Quitobaquito Springs near the Arizona-Mexico border, but ...