A lone male jaguar, nicknamed El Jefe, once roamed the mountains of southern Arizona; he was last recorded in March of 2016. Soon afterward, in December, another lone male was photographed in the Huachuca mountains. Any female attempting to join them and reestablish the species in the United States has to cross many obstacles on her way from Mexico. In all likelihood, she would come from central Sonora, and travel north-northwest along isolated mountain ranges, until reaching the infamous Border Wall, a series of infrastructures already dividing Mexico and the U.S. She might still be able cross the wall through some of the gaps left in remote areas, but before she reaches that testament to fearmongering, she could give up the journey as she comes across the increasingly wider Highway 2, which splits the Sky Islands region in the northern Mexican states of Sonora and Chihuahua.
Highway 2 runs somewhat parallel to the international border along one of the most biodiverse regions of North America. From the town of Ímuris in Sonora to the small community of Janos in Chihuahua, this highway creates a rift in a landscape that must remain open to provide connectivity for jaguars and other wildlife including the recently reintroduced Mexican wolves in Chihuahua.
Preliminary results from research conducted by Sky Island Alliance, Cuenca los Ojos and Wildlands Network indicates that as many as 2,000 vertebrates are killed each year in the Sky Islands stretch of Highway 2, adding deeper insight to individual reports of large carnivores killed recently, including bears and cougars.
We are using this research to inform transportation authorities in Mexico City regarding actions necessary to mitigate the effects of the recent expansions and to reduce the risks of wildlife-vehicle collisions. We think 2,000 animals killed each year by cars is something well worth worrying about… so is a 200-pound mule deer buck smashing through your windshield when you’re doing 60 miles an hour.
Unknown Risks and Known Solutions
While there are no concrete figures for Mexico, it is estimated that, in the United States, wildlife-vehicle collisions are responsible for 200 human deaths, 26,000 injured motorists and 8.38 billion dollars in losses, every year. The number is likely smaller in Mexico, given that the overall size, abundance and distribution of large fauna are lower, yet why should anyone die in such a collision if there are tested ways to avoid them.
We recently presented transportation authorities in Mexico City with the first results of our research, along with existing data on jaguar corridors and insights from local landowners. We included specific recommendations for infrastructure necessary to mitigate the effects of the recent expansions and to reduce the risks of wildlife-vehicle collisions. Our first maps identify places along Highway 2 where collisions with wildlife are more likely to occur, information which helps us locate the places where a quick and relatively cheap intervention can make this highway safer for everyone. A first step will be to place fencing along the highway that can serve as a sort of funnel, guiding wildlife to specific bridges and culverts already in place that can serve a dual purpose by also allowing the flow of fauna.
Later on, infrastructure may include some of the first, if not the first, wildlife bridges in Mexico. Along with underpasses, such bridges would keep corridors open for many animals, certainly some of the many black bears in the area, potentially some female jaguars bound for the U.S. to start a family in Arizona, maybe even a wandering pack of Mexican wolves.
These are all proven mitigation measures that have had positive effects in many parts of the world and are being implemented elsewhere in the borderlands region.
Pinpointing Specific Crossings
The corridors jaguars use, have been somewhat known to researchers for almost a decade but it was only in 2015 that a thorough computer model, based on verified jaguar records and known habitat preferences, was produced through a collective effort of the US Fish & Wildlife Service (USFWS), the Wildlife Conservation Society (WCS) and the Jaguar Recovery Team, which includes experts from both the U.S. and Mexico. This model shows the places likely to be used by jaguars along the western portion of Mexico and into Arizona as far north as Interstate-10.
The vast geographic extent of this model required a compromise in detail and although the general areas of intersections between corridors and highways are easily identifiable, the resolution is not sufficient to advise on specific locations for wildlife crossings. Now we are teaming up with Conservation Science Partners to create a finer resolution jaguar corridor model for the Sky Islands region following the logic of the one made by the USFWS and WCS. Officials in the Mexican federal transportation agency SCT (Secretariat of Communications and Transports) have expressed an interest in this product as it could inform future developments for many years to come.
Bridges: Physical and Metaphorical
Last September a binational collaboration coordinated by Wildlands Network, for safer highways and improved wildlife connectivity, brought together representatives from SCT and Arizona’s Regional Transportation Authority during a trip meant to give Mexico City officials a first-hand look at Tucson’s newest wildlife crossings on Oracle Road. Inspiration and know-how provided by participants in the project is now lighting the way for future wildlife crossings in Mexico.
Much of the interest shown by authorities in Mexico and the U.S. revolves around the allure of the jaguar, yet we are certain that wildlife crossings, when built, will serve many other species, including Mexican wolves, whose recovery depends on several, constantly moving parts. Safe corridors for wolf dispersal are indispensable if they are to reach their cousins in New Mexico and Arizona. Understanding how Highway 2 will affect them is next in line in our corridor modeling efforts.
And as the construction of a useless and destructive border wall fills the news Americans and Mexicans, particularly those of us living in bordering states, need to recognize that if they are to hand over richly diverse and biologically healthy countries to the next generations they need to support wildlife corridors that span across international borders; corridors that can keep lands and hope open for carnivore populations shared between Mexico and the United States. For that we will need to tear down the wall and build some wildlife crossings.
To help us bring this ambitious project to fruition, support our Borderlands Campaign and increase the odds for future females jaguars trying to reach Arizona’s lone males.