Quenching Bats’ Thirst in the Parched Southwest

ater is the new gold in the southwestern United States. High temperatures, increased evaporation of surface water, and reduced snowfall have resulted in unprecedented water shortages in western reservoirs, according to a report from the Climate Office of the National Oceanic and Atmospheric Administration (NOAA). The report projects broad threats to drinking, agricultural, and tribal water supplies, noting that hydropower generation, fishing, and recreational activities are also at risk. These shortages also impact wildlife, including bats.

BCI Water for Wildlife Field Lead, Ethan Sandoval, speaks with boots-on-the-ground knowledge of the impact of diminishing water resources on North American bats.

“The U.S. Southwest has the highest diversity of bats but the lowest density of water resources,” Sandoval says. “With the increasing drought in the Southwest, effects on bats will only become more dire. Water restoration projects are absolutely and unquestionably necessary to maintain bat populations.”

BCI has built a well-respected team of landscape restoration specialists who are working on water restoration projects in Arizona and New Mexico—for now. Sandoval anticipates that BCI will soon be engaged in more projects across a wider geographic area.

“At BCI, we are uniquely positioned with our expertise and technology to assist federal and state partners in saving bats, of course, but improving water sources will also help save numerous other species,” Sandoval says.

BCI is working in areas that have experienced some habitat degradation, and Sandoval calls these preemp-tive projects.

“We’re trying to get ahead of need and avoid complete breakdowns of ecosystems,” he says.

Some of BCI’s recent restoration projects include:

BCI’s work at Mud Spring entails partnering with the BLM to build a pipe-rail fence around the springs, then cleaning out an area filled with invasive plant species to create a depression that pools the water to support bats and other biodiversity.

“At this point, we don’t expect to plant new vegetation but, instead, anticipate that native vegetation will recolonize to create a lush oasis,” he says.

In the mountains and a riparian corridor (a significant low-elevation riverside) near Patagonia, Arizona, BCI recently partnered with Borderlands Restoration Network to convert an old cattle tank into a wetlands pond. The Patagonia and Santa Rita mountains located in this area have the greatest bat biodiversity in the U.S.

BCI’s work required enlarging and deepening the old cattle tank, compacting native clay soil to prevent water loss, and adding logs and vegetation to create habitat and a natural-looking water source. Being attentive to how bats and other wildlife use the water resource is vital to its success, Sandoval says. The new pond supports migrating bats, including agave-pollinating lesser long-nosed bats (Leptonycteris yerbabuenae) with a stable water source. Project partners hope this human-crafted pond will also appeal to jaguars, a large cat species protected under the U.S. Endangered Species Act. Individual jaguars have been documented returning to their former range in southeastern Arizona from northern Mexico and are suspected of using this corridor.

Like BCI’s water restoration project at Mud Spring, the Zuni Mountain site has water flowing underneath the wetland surface. Sandoval points out how uncommon this is in the Southwest and says that these water features can be easily destroyed without intervention. BCI has built nearly two miles of fencing around the forest wetlands through funding from the New-Land Foundation and other donors, and the U.S. Forest Service plans to install additional fencing.

“A few years ago, I could never have imagined the projects we are taking on now,” says Sandoval. “But as we look ahead, we’re preparing for more work assuring resilient landscapes.”