Volunteers help boost barn owl numbers in Butler County
Volunteers placed more than 500 boxes to be homes for barn owls around Butler County and in other counties in the past 10 years as part of an effort to boost the creatures' numbers.
“Barn owls are a species of concern in Pennsylvania. We are concerned about their numbers dropping,” said Heather Jerry, director of recreation in Marshall and a longtime volunteer for the Moraine Preservation Fund, a volunteer group that works to maintain Moraine State Park and on general environmental projects.
The barn owl is the most widespread land bird in the world and lives in every continent except Antarctica. Its decline in Western Pennsylvania and elsewhere is partially linked to the disappearance of the grasslands where it flourishes.
Listed as a species of special concern by the Pennsylvania Game Commission and as endangered by the state of Ohio, barn owls are particularly effective at limiting the populations of rodents such as voles, mice and shrews.
The effort to revive the owl's population in Pennsylvania has involved hundreds of volunteers over more than a decade, Jerry said. “We are proud of what we accomplished. There is much more awareness of barn owls than there was,” she said.
Barn owls are cavity nesters, meaning they build nests, lay eggs and raise young inside sheltered chambers. The barn owl boxes the fund's volunteers built provide a shelter for them. The boxes are not especially easy to hang or mount, said Mark Browning, a zoologist and onetime trainer with the Pittsburgh Zoo & PPG Aquarium.
“It takes two to four people to put up a wooden box,” he said. The boxes are bulky and require climbing and lifting.
Browning developed and patented a lighter plastic barn owl box and is the owner of the North Side-based Barn Owl Box Company, which sells the boxes.
In addition to the installation of barn owl boxes, the preservation fund and the zoo in 2005 fitted 16 young birds with satellite transmitters, released them from three western Pennsylvania locations and tracked them for nine months.
The study examined movements of the owls and their accompanying habitat usage, occupation of winter territory and spring movement.
“As far as we knew, this had never been done with barn owls,” Browning said.
Browning said the project led him to believe that barn owl boxes are an essential part of restoring the bird.
“Breed-and-release is not the best method to re-establish an animal like the barn owl. These birds fly away and have a tendency not to come back,” said Browning, who is conducting a study of barn owls in Lodi, Calif., a wine region.
The preservation fund also ran projects to restore various bat species and the osprey, a raptor.
Pennsylvania's Game Commission officials are collecting information on barn owl sightings.
When the data are compiled, biologists will be able to determine where conservation initiatives should be directed. The effort may include erecting nest boxes and documenting productivity, according to the commission.
Rick Wills is a staff writer for Trib Total Media. He can be reached at 412-320-7944 or at firstname.lastname@example.org.