Media & Education
BATS Magazine

Volume 20, Issue 2, Summer 2002

Bats & Mines

Saving the Last Sanctuaries for Millions of Bats

The old iron mine had been abandoned for decades. Its entry shaft, a gaping maw some 300 feet (91 meters) straight down, was a hazard the town of Iron Mountain, Michigan, didn't want to live with any longer. So plans were laid in 1992: Tons upon tons of dirt would be dumped to fill the hole that had been cut by hard-rock miners as much as a century before. Then they found bats.

A local caver, Steve Smith, wanted to explore the old mine before it was permanently sealed. What he and his friends found was seemingly endless thousands of bats clinging to the mine's walls and ceilings. Little brown and big brown bats (Myotis lucifugus and Eptesicus fuscus) had formed one of the largest hibernating bat populations in America, and they were about to be trapped inside the Millie Hill Mine. Smith called Bat Conservation International.

BCI Founder Merlin Tuttle contacted the Michigan Department of Natural Resources, which assigned biologist Bob Doepker to help. Unfortunately, neither the mining company nor community officials understood the importance of bats. Phone calls went unreturned as local leaders apparently hoped to hasten the project before anyone could interfere.

So Tuttle headed for Iron Mountain. Instead of causing embarrassment through the news media, he spoke at two elementary schools, where Zoie, BCI's flying fox mascot, enchanted the children. He invited them to a special program at the county library. Two nights later, despite sub-zero weather, more than 200 youngsters showed up with their unsuspecting parents, who included leading business people and city officials. After Tuttle's talk on the values and needs of bats, local companies donated materials, citizens volunteered their time and skills, and an enthusiastic partnership was formed to save the bats.

By the next summer, the mine entrance was stabilized and spanned by a special steel cage and gate that was hoisted onto a concrete foundation. People were protected while the bats were given free access. The Millie Hill effort preserved a safe haven for hundreds of thousands of hibernating bats, but its impact reached far beyond Iron Mountain.

The area's leading mining company, Cleveland Cliffs, was so pleased with the outcome that it offered to co-host a workshop on how to save mine-dwelling bats of the Great Lakes Region, and the door was opened for years of collaboration between BCI and the mining industry.

The success of education without confrontation and of nurturing collaborations among disparate partners became a model that set the stage for the founding of BCI's North American Bats and Mines Project in 1994. Wildlife biologist Dan Taylor was its first director.

Begun as a partnership with the U.S. Bureau of Land Management, the project coordinates efforts to protect mine-roosting bats throughout North America. BCI's Bats and Mines Project has grown into an extensive network of local, state, and federal agencies, as well as private entities (including some of America's largest mining companies), working together to manage abandoned mines as bat sanctuaries. Thousands now are safe, not only for humans but also for millions of bats.

The challenges facing the Bats and Mines Project were -- and remain -- critical. Without this almost unheard-of coalition of miners and conservationists, vast numbers of American bats would have been doomed when their last refuges were bulldozed or otherwise sealed during mine safety and reclamation efforts.

By the 1990s, more than 95 percent of the known population of little brown bats relied on old mines to survive winter, mines that mostly would have been sealed without the Bats and Mines Project and its partners. This species, though still ranked among North America's most abundant, could well have become a candidate for endangered listing. In the project's Great Lakes Initiative alone, hundreds of miles of copper-mining tunnels, favored by the largest remaining populations, were set aside as permanent sanctuaries for migrants from a huge region.

The Indiana bat (Myotis sodalis), a longtime endangered species, had already lost its key hibernation caves to commercialization before this project began. But after Illinois' Magazine Mine was protected in 1996, Indiana bats rebounded dramatically in this newly available home. In the first three years of protection, numbers zoomed from less than 100 to an astonishing 9,000. Due to its location, ideal temperatures, and sprawling passages, this one mine has the potential to someday shelter more Indiana bats than are currently known in all of North America combined.

The Bats and Mines Project is scoring similar successes in the American West. Dozens of mines have been set aside for the threatened Townsend's big-eared bat (Corynorhinus townsendii), reversing population declines at many locations. For example, gates were installed at the Mariscal Mine in Texas' Big Bend National Park to protect a now-growing nursery population that numbers in the thousands, the largest known anywhere.

Over the past century, countless mines of all sizes were worked and abandoned across the continent. Many of them have become havens of last resort and they now shelter a large proportion of America's remaining bats. BCI and its partners have saved millions of these bats, but many more remain at risk.

Surveys continue to identify mines favored by bats, and ongoing research is determining their needs. America's bats will need continuing help from the North American Bats and Mines Project for years to come.

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