Going to Bat for Bats Saves Money, Species

WHAT eats tons of mosquitoes, hangs around in old mines, and can save farmers billions of dollars?

Bats! They are the focus of a public-private partnership to keep the pest-eating and crop-protecting animals from becoming endangered.

The North American Bats and Mines Project, announced recently by the Department of the Interior and Bat Conservation International (BCI), is surprisingly simple: Instead of closing abandoned mines by blasting them shut or filling them in, entrances to mines would be covered with metal ''bat gates''; bats can fly in, but humans stay out. In many cases, the gates are cheaper than blasting or filling -- not to mention the economic and social costs averted by keeping bats off the endangered-species list.

The project is aimed at preserving the United States' 43 bat species, six of which already are endangered. Another 19 species are candidates for listing, says Merlin Tuttle, who founded Austin, Texas-based BCI in 1982 and came up with the bat-gate idea. Bats have increasingly moved into abandoned mines as other habitats like forest have become more scarce. Humans' general distrust of bats has not helped these animals, which do far more good than most people realize, Mr. Tuttle explains. Bats help control insect populations that otherwise could lead to costly crop spraying or losses.

Even the loss of a small bat population can have far-reaching consequences. Just 150 big brown bats eat enough cucumber beetles to protect farmers from 18 million of the beetles' crop-eating larvae. These insects may cost farmers billions annually. Besides eating pests, bats also play a critical role in pollinating plants and dispersing seeds.

The steel-grid bat gates cost $3,000 to $7,000 each. The US has 500,000 abandoned mines, an undetermined number of which are suitable for bat dwellings. BCI will spend $50,000 on the project this year; the Bureau of Land Management has contributed another $50,000.

Bat gates and other preventative approaches to conservation are looming larger as the Endangered Species Act (ESA) faces reauthorization by a regulation-weary Congress this year.

More than 900 animal species have been listed as endangered (some 3,700 more await research) since the ESA's inception in 1973. Six species have recovered and are off the list, including American alligators and Arctic peregrine falcons. Recovering an endangered species can cost millions, often with little hope of a species becoming viable again.

Even economic alternatives such as bat gates are not always met with enthusiasm. When Tuttle learned of plans to fill an abandoned mine inhabited by a million bats in Iron Mountain, Mich., he contacted the Michigan Department of Natural Resources (MDNR) and proposed using bat gates. But attempts by Tuttle and MDNR to sell the idea to local officials were rebuffed. ''Everybody we called found a convenient excuse not to return calls,'' Tuttle says. So he presented programs on bats at two local elementary schools and invited children to bring parents to a program at the town library.

''We put out 20 chairs, and 300 people came,'' he says. ''We saved the city a bunch of money.'' Citizens volunteered labor, and local corporations donated materials to install the bat gate.

''Most people fear bats,'' says Walt Summers, district conservationist of the US Department of Agriculture's Natural Resource Conservation Service in Kingston, Mich. But ''fearing bats and accepting bats are two different things.'' Although most people have not warmed up to the furry creatures, Mr. Summers says that because of the Iron Mountain project, people have become more understanding. Rather than kill the animals that like to hang on rafters outside storefronts, he sees people trying to remove them unharmed.

Summers is now seeking funds to catalog mines in the area and find candidates for gates. ''The Michigan Department of Natural Resources had not taken bats as a serious issue,'' he says. ''We stumbled into something that people became very concerned about.''