Somewhere among the rocky pinnacles of southern Arizona’s Chiricahua mountains roams the last known jaguar in the US. The dark-spotted big cat, a male known as “Sombra” to wildlife researchers, wanders between three mountain ranges, hunting for deer and piglike javelinas and, perhaps, searching for a mate. The last known female jaguar north of the Mexican border was shot by a hunter in 1963, so Sombra’s chances of producing offspring to continue the US population are near zero. This month, conservationists called on the federal government to stop big cats like Sombra from going extinct in the US by reintroducing jaguars to the region and increasing protections for the animals’ habitat. The non-profit Center for Biological Diversity petitioned the US Fish and Wildlife Service to create an experimental population of jaguars in the Gila national forest, a sprawling, rugged 3m-acre wilderness in New Mexico dotted with pinyon pines. They also called for protections for millions of acres of wildlands in New Mexico and Arizona, including the tracts where Sombra currently lives. “Jaguars evolved in North America eons ago and lived here until people killed them off for their beautiful pelts and to eliminate a threat to livestock,” says the petition. “Over 50 years since the jaguar was placed on the endangered species list, we should not be facing the realistic prospect that this sole jaguar in Arizona will be the last.” Researchers believe the cats, known for their reclusive nature, once populated a huge swath of North America, stretching from the Carolinas to California. Now, a small, struggling population lives in northern Mexico near the border and the sleek, long-tailed cats have been known to wander north into the US. But this population has little genetic diversity and faces its own risks of extinction, the researchers say. Meanwhile, the jaguars’ ability to venture into the US is hemmed in by barriers, including highways and the US border wall. Michael Robinson, the conservation advocate who drafted the petition for the center, said jaguars could be drawn from healthier wild populations in South America or in southern Mexico, or from captive cats at zoos or rescue centers for the reintroduction. In Argentina, a “rewilding program” is under way, in which the cubs of captive jaguars are raised in a huge wildland enclosure designed to cut them off from any human contact. They learn to hunt before a gate is opened remotely to allow the cats to return to the wild. Whatever approach is chosen would involve years of study, negotiation and planning, Robinson said. The petition argues that the federal government, which funded a team of hunters to exterminate jaguars and other big predators that operated at least into the 1960s, has the responsibility to save native animals now facing extinction. “The bottom line is that the Endangered Species Act makes it a federal responsibility to recover endangered species,” said Robinson. “We are pointing out that they haven’t done so. They don’t have a plan to save the jaguar and it’s time to take a different approach.” A ‘turning point’ for Washington Not much is known about the daily lives of the jaguars in the US, because through most of American history, the focus has been on shooting them, not studying them. Robinson said ranchers would round them up with packs of dogs. He also explained that in 1915, the federal government appropriated $125,000 to fund a team of hunters, charged with the task of “destroying wolves, coyotes, and other animals injurious to agriculture and animal husbandry”. Several jaguars have been killed even since they were given protection in 1972. In 2009, the Arizona state game and fish department killed a male jaguar named “Macho B”, after he was wounded in a trap that was allegedly set by an agency contractor. At the time, Macho B was the last known jaguar in the US. Sombra was first spotted on research cameras in 2016. Researchers believe he was born in Mexico and wandered north. His name, which means shadow in Spanish, was given to him by a group of Tucson middle school students. Since 1964, at least nine distinct jaguars have been spotted on US lands in the only way researchers ever see them in the wild: by using trip cameras with night vision and motion detector technology. But all are believed to have been male. A spokesperson for the US Fish and Wildlife Service, which has been sued by conservation groups in the past to get it to take more steps to ensure the jaguars’ survival, said the agency cannot comment on petitions while they are under review. But, responding to a 2021 study concluding New Mexico and Arizona would offer suitable habitat for a reintroduction of jaguars, an agency representative told National Geographic that an analysis of jaguars and their habitat was “ongoing”. Robinson said he hoped Joe Biden’s wildlife-friendly appointments, including the secretary of the interior, Deb Haaland, the first Native American to hold the post, will come to represent a “turning point” in how the US government treats predator populations. However, opposition from cattle ranchers will probably be fierce. The New Mexico Cattle Growers’ Association did not return calls from the Guardian. But it has vehemently opposed plans to restore Mexican gray wolf populations in the south-west, calling them a “death warrant” for rural populations in the region. A spokesperson, speaking to the Albuquerque Journal, called an earlier proposal to save the jaguars’ habitat “ridiculous”. A 2021 study led by ecologist Eric Sanderson of the Wildlife Conservation Society (WCS) showed that an expanded territory for the jaguars in the south-west, similar to the one proposed in the petition, could accommodate 90 to 150 jaguars. That’s a large enough population to be sustainable. The study concluded that restoring the jaguars would have little effect on human or livestock populations. It cited a 2001 book which found no evidence of anyone ever being killed by a jaguar in the US. “Reports of unprovoked attacks by jaguars are extremely rare,” that book said. “And most of these take place prior to 1850 so they are now nearly impossible to verify.” Jaguars, which the federal government has described as “cryptic and difficult to detect”, have been known to occasionally attack livestock. But the study cited evidence collected from Mexican jaguar populations, suggesting that livestock mortalities would be expected to be very few. “Such losses may be minimized by proactively deploying mitigation strategies”, such as employing range riders to scare off predators from cattle in specific hotspots and compensating ranchers for lost animals, the report said. It also concluded a reintroduced jaguar population could provide ecotourism benefits, similar to the reintroduction of wolves in Yellowstone national park, which was estimated to generate $5m a year in ecotourism revenues. “The fact that we spent something like 400 years trying to get rid of carnivores in the United States makes it a big idea for us to try and bring them back,” Sanderson said. “Ultimately, it’s about what it means to be an American and what it means to be an American in nature. To me, it’s not complete and it’s not right without jaguars.”