Jaguars are the only species of big cats found in the American continent. They range as far south as Argentina, and once ranged as far north as the Grand Canyon in the United States. Today, the northernmost breeding population is in the northwestern Mexican state of Sonora, just south of the Arizona border.
In the Americas, the jaguar has long been an icon and symbol of power and connection to the spirit world in mythology, philosophy, culture, and art. Jaguars are apex predators with diverse diets that include more than 85 different prey species. This gives them a specific but prominent role in each ecosystem where they are found.
The International Union for Conservation of Nature classifies jaguars as “Near Threatened”, with total population estimates ranging from 64,000 to 173,000. But evidence shows that local populations across the continent are declining at an alarming rate. The total range of jaguars has been reduced by more than half in the last 70 years, mainly due to hunting and habitat loss.
Could jaguars return to the southwestern United States? Some experts believe it is possible. Jaguars from populations in southern Mexico could recolonize their former territories in Arizona and New Mexico, or humans could reintroduce them there.
We study biodiversity and wildlife conservation in the US-Mexico border areas and have documented jaguar movements near the border. From our research, we know that there are only two main corridors on the western border that jaguars could use to enter the US.
In our view, maintaining these corridors is crucial to connecting fragmented habitats of jaguars and other mammals, such as black bears, cougars, ocelots, and Mexican wolves. Increased connectivity, linking small patches of habitat into larger networks, is a key strategy for conserving large animals that are widely distributed and for maintaining functional ecological communities.
Jaguars in North America
The arid environment of the southwestern United States has naturally limited the range of jaguars in North America. Once these cats were top predators in the forested ecosystems of the southwestern US, hunting and predator control programs decimated their populations in the 19th and early 20th centuries. The last female jaguar in the US was killed in Arizona in 1949.
In 1996, an outdoor guide and hunter photographed a male jaguar in the Peloncillo Mountains of southeastern Arizona. Since that date other jaguars have been identified, but no females or cubs have been reported.
In contrast, jaguars are known to be present in the northeastern corner of the state of Sonora in Mexico. Here, the Cajon Bonito Creek, which flows from the western slopes of the San Luis Range on the Continental Divide, supports jaguars and other large animals, including black bears, American beavers and ocelots.
El Bonito, a jaguar that lives on the border between Mexico and the United States, using the Cajon Bonito area in northeastern Sonora.
For two decades, the land surrounding the creek has been under a restoration program run by Cuenca Los Ojos, a nonprofit organization that works to protect and restore land on both sides of the border. They are now part of a voluntary program of protected areas under the Natural Protected Areas system of Mexico.
To the east, the Janos Biosphere Reserve includes habitat for jaguars. To the north and south, a combination of dedicated conservation ranches and protected natural areas provides the habitat connectivity jaguars need to move between Mexico and the US.
Crossing the frontier
In 2021 we filmed a young jaguar we named El Bonito roaming the US-Mexico border. Each individual jaguar has a unique pattern of spots on its skin; when we acquired video of both flanks of the cat, we realized that we were actually seeing two jaguars in our study area.
We nicknamed the second jaguar Valerio. Lately he has been seen more frequently than El Bonito in the Cajon Bonito creek area.
After El Bonito, a second male jaguar appeared in our camera traps in the border areas between Sonora and Arizona. We nicknamed him Valerio.
Male jaguars have to disperse as they become adults to find available territories and potential mates. Females tend to occupy areas close to where they were born, a common pattern among mammals. The size of a female jaguar’s territory depends on the abundance of prey and the availability of shelter. Male jaguars will travel through various female home ranges to increase their mating opportunities, so male home ranges can measure approximately 15 to 400 square miles (35 to 1,000 square kilometers).
Bonito and Valerio were juveniles when we first recorded them. We filmed Valerio for the first time at our study site in January 2021. Since then, both cats have been using the creek as a corridor. Recent videos show Valerio rubbing his cheek on a fallen tree, suggesting that he is establishing territory in this border area.
At our study site, we have recorded both jaguars just 3 kilometers (2 miles) south of the US-Mexico border. North of this site is Guadalupe Canyon, a natural corridor in the Peloncillo Mountains that reaches the US at the Arizona-New Mexico border.
In 2021, the border wall was built in Guadalupe Canyon, with a stop on the line between Arizona and New Mexico. The New Mexico portion of the Peloncillo and San Luis mountain ranges remains open.
Government agencies and conservation organizations from the US and Mexico are working together to restore Western species from the brink of extinction. Growing populations of Mexican wolves, black-footed ferrets, California condors and bison offer hope that recovery is possible for jaguars, too.
According to a 2021 study, the jaguar population in Mexico has increased over the past decade and is now estimated at 4,800. As the number of jaguars in Sonora increases, so do the chances that females could reach the border and potentially mate with the male jaguars we have documented there.
Habitat loss and illegal killings remain the main threats to jaguars in northern Mexico. The creation of protected natural areas that could support breeding populations and offer routes for northward expansion would help accelerate the natural recolonization of jaguars in the US Multiple institutions and scientific research projects have highlighted the need to keep open natural corridors to maintain habitat for diverse plant and animal communities
In addition to jaguars, our camera traps have identified 28 other mammal species, including ocelots, cougars, and black bears. All of these animals have at least some need for connected landscapes if they are to survive long-term.
In our view, enabling jaguars to naturally recolonize suitable habitats in the US is a unique opportunity to encourage animal movement in border areas. Keeping these landscapes connected will benefit all species in this ecologically unique region that serves as a source and pathway for wildlife.
This article was originally published on The conversation by Ganesh Marin at the University of Arizona and John Koprowski at the University of Wyoming. Read the original article here.