A walk at dusk on a balmy summer’s evening through Wertz’s Red Bridge at the Berks County Heritage Center has once again become a thrilling adventure.
The swooping and darting bats in the bridge are back.
After their populations in Pennsylvania and throughout North America were nearly wiped out by white-nose syndrome, a fungus infection that disrupted their winter hibernation, bats have begun a tentative comeback.
Thursday at 7 p.m., Albright College’s Dr. Karen Campbell will present her long-running program on the bats at the covered wooden bridge, sponsored by the Berks County Parks and Recreation Department.
A former professor and current provost at the college, Campbell has been studying the bats at the bridge in Bern Township since 1990 and witnessed their abrupt decline when millions of the nocturnal creatures perished across the continent from the syndrome.
“White-nose syndrome was first detected in New York state in 2006, and then in northern Pennsylvania in 2009,” Campbell said as she stood inside the bridge last week on a scouting mission for Thursday night’s program. “There were still bats at the bridge that summer, and I hoped they were safe, but of course, that didn’t last.”
‘Getting back up’
In the early 1990s, Campbell had found as many as 1,500 to 2,000 bats colonizing the 155-year-old structure.
In the summer of 2010, she saw fewer bats at the bridge and then none in 2011.
“It was just heartbreaking,” Campbell said.
In 2017, she noticed that a few bats had returned to the bridge, and the number has been steadily growing since.
“I did a really quick count today, and it’s hard to tell exactly, but there are at least a few hundred bats here,” Campbell said. “So the population is getting back up.”
Researchers believe that the bats have developed some resistance to the fungus, as bats in Europe, where the disease originated, had done. Also, bats may be gaining more weight before hibernation to help them survive the interruptions in their torpor the fungus causes.
Place to roost
Campbell reached into a rafter and cradled in her hand a little brown bat, the main bat species at the bridge, and gave it a quick examination.
“This is a female bat that had given birth this year,” she said. “You could tell because she had been lactating. It’s good to see that the bridge has turned into a maternal colony again.”
Campbell noted that she has permits from the Pennsylvania Game Commission and the U.S. Fish and Wildlife Service that allow her to handle and band bats.
“The bridge provides a really good roost,” she said. “The bridge has been here for a long time, and bats are very faithful to where they roost. I have banded bats here and then caught them 20 years later.”
The big brown bat, a close relative of the little brown bat, can live to be 32 years old, Campbell said.
“A female bat that’s born here will come back here to give birth to her young,” she said. “They have only one young a year, but they’ll do it year after year after year.”
In her programs, Campbell tries to lessen people’s innate fear of bats.
“I like them to know that bats are mammals just like us, and so they share a lot of the same characteristics,” she said. “And that’s part of what makes them interesting to study. Because they are very social, they do a lot of things that kind of remind you of humans sometimes. And I think that makes them more personable to us. We get the sense of, ‘Oh yeah, we do that,’ so it makes them fun to study.”
Campbell’s program is one part of the ramping up of activities this summer and fall in the county parks since the pandemic.
There’ll be a full slate of activities going into the fall, said Daniel Roe, the historic resource supervisor with the Berks County Parks and Recreation Department.
“We’re bringing back some of the traditional programs that have been popular with our audiences in the years past, like Karen’s bat program,” he said. “But we’re also looking at this as an opportunity to try some new things upcoming here in the rest of this season and then rolling into the following year as well.”
One of the highlights will be a Museum Day activity Sept. 17 at the Gruber Wagon Works that’s held in conjunction with Smithsonian magazine. Admission will be free that day.
“We’re going to be demonstrating the running belts and line shaft system in the Gruber Wagon Works for the public between 10 a.m. and 4 p.m.,” Roe said. “We’re trying to add new activities to some of these events that we’ve done before.”
To keep up with all of the parks’ activities, visit the department’s Facebook page or website at www.co.berks.pa.us/Dept/Parks/Pages/default.aspx.
Oh, one more question for Dr. Campbell.
What do you do when a bat is flying around inside your house?
“You know what,” Campbell laughed, “a friend just texted me around midnight last night, ‘We have a bat in the house.’ ”
Contrary to folklore, bats are not blind, she said.
“But, inside when they’re echo-locating, it must be very deafening because their echoes are really loud and bouncing off of everything,” Campbell said. “So if you can help them switch to vision, that works.
“If you could turn the lights on outside and open the door and turn the lights off inside, it backlights the opening, and they’ll fly through it. That’s the trick.
“You just have to be brave enough to turn the lights off inside.”
Source: Berkshire mont