With Halloween just around the next dark corner, John E. Hutchison Jr. might not mind being called a "bat man" who is a bit batty about his pet project -- building a bat-roosting habitat at Moraine State Park in Butler County.

Mr. Hutchison, of Saxonburg, an engineer and real estate developer, is working with some volunteers with the Moraine Preservation Fund to create a "BATitat" at the park, an especially fitting undertaking in October when thoughts turn to goblins, ghouls and bats.

The Moraine Preservation Fund is a nonprofit group that supports the park in a variety of ways: developing wildlife restoration projects, such as the osprey and barn owl reintroduction programs; creating the native plant and butterfly trail; staffing wildlife education classes; operating a gift shop and nature center at the park's boat launch; manning the Nautical Nature, a 45-passenger enclosed pontoon boat that offers interpretive tours on Lake Arthur in the park; and, now, creating a bat condo, so to speak.

BATitat volunteers have been working this month to ready a roosting station capable of housing a maternity colony of up to 6,000 female bats and their young.

The purpose of the bat-roosting habitat project is twofold: to protect the region's bat population and to reduce the nuisance of bat colonies taking up residence where they're not wanted, such as in your attic, said Cal Butchkoski, a wildlife biologist with the Wildlife Diversity section of the Pennsylvania Game Commission.

The only mammal that flies, a bat should be a welcomed neighbor if for no other reason than its appetite for pesky insects, such as mosquitoes and tent caterpillar moths. "The Little Brown [the most common bat species found in this area] can eat a couple thousands insects per hour," Mr. Butchkoski said.

Despite that, many consider bats to be pests. "People aren't too tolerant of bats in their attics," Mr. Butchkoski said. And residential roosting by bats is happening more often as development spreads. Large trees that made for perfect nesting grounds have been cut down. Old churches with steeples that allowed bats to roost high in the cold morning and descend to cooler areas as temperatures rose have been demolished.

Female bats have been forced to look for new homes, and residential attics can provide a comfy environment for a maternal bat that needs to conserve her body's energy for gestating and nursing pups.

"We're seeing more and more cases of larger concentrations of bats in fewer buildings -- thousands of bats in an attic. That can be pretty burdensome to a homeowner," Mr. Butchkoski said.

He helped design what he affably calls a "bat condo" -- a manmade roosting station -- by replicating the internal conditions of a church steeple that was home to thousands of maternal bats.

Project BATitat will convert an old, 18-foot osprey nesting tower in the park into a scientifically designed condominium for bats. The tower is near the Department of Conservation and Natural Resources Regional Office on Old Route 422 within the park. The habitat will follow specifications from the state game commission's Bureau of Wildlife Management.

It is made of wood and is 8 feet by 8 feet and 8.5 feet high. It will sit 18 feet in the air on a 15-foot-square deck.

"It is designed so they can get in easily, then move up and down" from hotter areas of the box to cooler areas of the box, Mr. Butchkoski said.

It's all about temperature, Mr. Butchkoski explained. "When the females come out of hibernation, they are looking for warm areas so they don't need to use a lot of energy to keep their body temperatures up. The energy can be focused on the gestation then the production of milk for the pups."

So, maternal bats will congregate in large groups following hibernation to give birth and then rear the young. While a few males will be found in roosting groups, most will hang singly in trees or under shutters. "[Males] don't congregate," he said.

Demolition of the old osprey tower was completed in late September, Mr. Hutchison said. Moraine park officials were glad to get rid of a dilapidated structure that was used successfully in the 1990s to introduce osprey to the park, he said.

The new bat habitat is expected to be ready by spring, just in time for the bats' abandonment of their winter hibernation homes in favor of summer roosts, where their young will be born in June and July.

HP Starr Lumber has provided building materials, and Boy Scout Troop 33 from Prospect is assisting volunteers from the Moraine Preservation Fund. The project has become the Eagle Scout project of troop member Mike Kozar, 15, of Butler County.

The preservation group is selling Project BATitat T-shirts to help fund the project. The cost -- after saving money by recycling some wood from the old osprey structure -- is estimated at $2,500, Mr. Hutchison said.

The importance of bats to the environment is underrated, said Mr. Hutchison, an Eagle Scout who has a passion of environmental conservation and preservation.

Nine species of bats are found in Pennsylvania, four of which are rare. All belong to the family Vespertilionidae, also known as evening bats.

Their populations are in decline worldwide. Of the 45 species found in the United States, six are federally endangered or threatened, and another 20 are listed as species of special concern by the U.S. Fish and Wildlife Service.

Pesticides and the resulting reduction in insect population have, in turn, impacted bat colonies as has the loss of natural habitat due to suburban development and industry.

That's where the helping hands of the Moraine Preservation Fund come in. "It may not be a natural home, but it's a home that they'll like … ."

BATitat T-shirts will be sold at the Owlet gift shop in the McDanel's boat launch area on the north shore of Moraine State Park. For more information on the preservation fund, go to www.morainepreservationfund.com.

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