Submitted PHOTO Stephen Zellner stands near the bat house on his Butler Township home.
It wasn’t until Stephen Zellner moved into his Butler Township home about 20 years ago that he realized there was already a tenant.
Many of them, in fact — bats.
Zellner called his brother, a wildlife conservation officer in Blair County, who explained what to do.
First, he got a bat house, a small box where bats can roost. Then he rubbed some of the bat’s droppings on their new home before installing it nearby. He waited until night, when the bats flew out of the house, then plugged the hole in his attic with foam.
When the bats returned, they flew toward their old home, but found it blocked. Suddenly, one went into the bat house, then another, and another and soon they all followed.
“And that’s where they stayed,” Zellner said.
Since that night, Zellner has had summer visitors from a maternity colony of bats. They are big brown bats, he said, one of the six species that regularly hibernates in the state.
Sometimes, he stands on the sidewalk near his bat box, chatting with friends. Most people don’t know what the black box on his chimney is, and he picks the spot because he knows the bats’ typical flight patterns.
“People are ducking and diving. I’m laughing,” he said.
Some drop a few feet then start fluttering up. Others fall close to 20 feet, before swooping skyward into the night.
Zellner suspects that white-nose syndrome — the fungal disease devastating some bat species, including several in Pennsylvania — is the reason he has been seeing fewer bat visitors in recent years. In some years, he had close to 70 bats in the bat house. He saw a decrease, and for the past three years, he has consistently seen about 20 adult bats there.
This year, Zellner is planning to take part in some citizen science.
His brother told him about the Appalachian Bat Count, a statewide monitoring effort to collect bat maternity colony data. The program’s goals are to gather baseline information on summer colonies, evaluate the impact of white-nose syndrome on those colonies and see how long-term trends correlate with the spread of the disease.
As the bats fly out, Zellner will count them, then look inside to see if any more are still roosting.
The survey data is due back to the game commission by Aug. 31.
Zellner plans to install two more bat houses on the property for the animals he calls “my bats.”
“They are amazing little creatures,” he said.