Above the town of Oro Valley is an open area designated as a wildlife corridor, allowing native animals to move with relative ease between the Catalina and the Tortolita Mountains.
The corridor has a serious roadblock that still needs to be addressed, where Oracle Road creates a dangerous obstacle for the animals. But, in many ways, it's a model for the kinds of wildlife linkages that need to be created and maintained in Arizona to keep our native species abundant and healthy.
To learn more about the linkages, I sat down with Melanie Emerson, the executive director of the locally based Sky Island Alliance, one of the organizations involved in maintaining and improving this corridor as well as other wildlife linkages around the region.
According to Emerson, the Catalina and Tortolita mountains are two of something like 40 mountain ranges covering a 70,000-square-mile area that stretches from northern Mexico through Arizona and New Mexico.
She had me picture the mountains as islands surrounded by a sea of grasslands and desert spaces. Wildlife, she said, especially larger animals like mountain lions, deer and bobcat, must be able to cross the flat lands – the seas – linking the mountain-islands. Male mountain lions, for instance, need a range of up to 600 square miles. To maintain genetic diversity, animals have to mate with others over a large area. Species survival depends on the ability to travel from mountain-island to mountain-island and to find healthy habitats when they arrive.
Ironically, as we make it easier for humans to live in the flat lands, we create nearly impassable barriers for native wildlife. Roadkill presents a stark reminder of the hazards these animals encounter crossing the ribbons of highways criss-crossing the landscape. Our homes and businesses create complex, confusing mazes of walls and fences for animals seeking passage.
The Sky Island Alliance partners with other nonprofits, governmental agencies and the scientific community to make the landscape friendlier to native species. It helps restore landscape. It decommissions unauthorized roads that cut through mountain areas, fragmenting the natural habitat. It works to restore riparian areas. Recently it participated in an assessment of wildlife linkages across Arizona. Emerson showed me a topographical map of the area covered with broad, double-sided arrows indicating the linkages. New highways and bridges can be built with wildlife corridors in mind, and passageways can be created over and under existing roadways to allow animals to cross the areas unharmed.
Cameras the organization set up in northern Mexico captured a nighttime photo of an ocelot, the first sighting in 40 years.
The Sky Island Alliance considers the corridor above Oro Valley extremely significant, as much for the process that created it as for the wildlife passage it provides. According to Janice Przybyl, the organization's wildlife linkages program coordinator, "The North Oro Valley wildlife corridor set a precedent for the number of groups coming together to preserve a wildlife linkage." The cooperation is a model for what needs to happen throughout the Sky Island region.
Constant monitoring is vital to understanding and improving the movement of wildlife in the corridor. To help with this, the Sky Island Alliance recruits and trains "citizen scientists" who are assigned specific strips of land, usually close to where they live, which they monitor for signs such as footprints, scat (feces) and scratches. The volunteers are given measuring tools and information sheets to fill out so their reporting can be used to create scientifically accurate maps of the wildlife traffic in the area.
The organization is always looking for more eyes on the ground. A new program called critters@ has been created to allow registered users to "report sightings of wildlife, both roadkill and live sightings. . . . [Users] will log-in, report, locate wildlife sightings on an interactive map and upload photographs."
Dave Safier is a regular contributor to Blog for Arizona.