Jaguars, the third-largest cats after lions and tigers and the biggest in the Western Hemisphere, used to live here. In the 1700s and 1800s people spotted them in Arizona, New Mexico, California and Texas. Sometimes the cats roamed as far east as North Carolina and as far north as Colorado.

As humans have encroached on their territory, the endangered cats' range has shifted south. Today it stretches from northern Argentina into Mexico's Sonoran Desert. But they cross into the American Southwest frequently enough for some conservationists to argue that they deserve critical habitat protection. Now, after years of legal wrangling, the U.S. Fish and Wildlife Service (FWS) has agreed. “We do plan on proposing to designate some critical habitat,” says Steve Spangle, field supervisor for FWS in Phoenix. “But we don't know yet where or how much.” The agency plans to announce its decision in July.

The question of whether or not jaguars deserve critical habitat reflects a broader debate in conservation circles. How does one prioritize spending among the many species that are slowly disappearing from the planet? Many experts believe the best way to help the species is to increase resources south of the border, where jaguars live and breed. But Michael Robinson of the Center for Biological Diversity, one of the groups that sued FWS to designate critical habitat, says the goal should be to help jaguars repopulate parts of the U.S. where they have gone extinct, especially since dozens were killed under a federal predator-extermination program that continued into the 1960s. It is important to look at a species' historical range and not just at “a snapshot in time,” Robinson contends.

Whatever critical habitat the government grants most likely will be small. In April an outline prepared by an advisory group to FWS focused on an area that includes the southeastern corner of Arizona and a tiny slice of New Mexico's southwestern corner, neglecting New Mexico's Gila National Forest and Arizona's Mogollon Rim, which Robinson says are prime jaguar habitat.

The subject “can be debated for a couple of more generations while the species goes extinct,” says Howard Quigley, a co-leader of the advisory group convened by FWS and executive director of the jaguar program at the wild cat conservation group Panthera. “But we need an area in which to focus now and get recovery actions under way.” At least it's a start.