At 9:30 p.m. on Saturday, 40 people stood in a circle, ankle-deep in snow in Sewickley Heights Park.

Snowdrifts reflected the dim light of the moon, lending the forest a crisp purple luminescence.

The group stood in silence, eyes lifted skyward, as Audubon Society volunteer Bob VanNewkirk played the whistling call of the screech owl through a speaker attached to his iPod.

The Owl Prowl, an annual event held by the Fern Hollow Nature Center, aims to educate the public about the owls of Western Pennsylvania and to instill an appreciation for birds of prey.

“It’s really hard to get away and go to a place where you’re completely immersed in nature,” said April Claus, the center’s naturalist. “For kids to get that experience is really important, because they never get it, not now.”

Before heading to the park, Saturday’s program began in the Nature Center with an interactive, kid-friendly presentation in which VanNewkirk discussed the adaptations that allow owls to survive in Pennsylvania — their camouflage coloring, incredible grip strength, sharp talons, and keen senses of hearing and sight.

VanNewkirk’s personal interest in owls began at age 11 when he attended a similar program, saw a screech owl and became enamored with the creature’s eyes.

“The more I saw and learned, the more I wanted to see and learn,” he said.

Now a member of the Three Rivers Birding Club, he leads outings at Beechwood Farms and in Sewickley Heights Park.

“I think we all grow up hearing stories about owls when we’re younger — about them being wise,” said Claus, nicknamed “the bird whisperer” for her ability to replicate the calls of screech and barred owls.

“I think it adds to the mystique that it’s night time, and people are interested in finding out what’s out there,” she said.

Wildbird Recovery, a nonprofit dedicated to the rehabilitation of distressed wildbirds, then brought out a live barred owl to give the audience a closer look at the features VanNewkirk had discussed. 

Due to previous injuries to the bird’s shoulder and beak, the owl is unable to be released and is now incorporated into educational programming.

“When you get to see a live bird of prey on someone’s glove, you can get quite close to it and can see its feathers, its body shape, its eyes, and you can learn an awful lot about it because of it’s proximity,” VanNewkirk said.

“It’s not something you see everyday. And it’s also really informative for the little guy,” said Daniel Gallagher, a Moon Township resident who attended the event with his 6-year-old son Michael.

Following the indoor presentation, Owl Prowl attendants zipped up for the chilly nighttime stroll through Sewickley Heights Park, during which Claus and VanNewkirk attempted to summon screech, barred, and great horned owls.

Standing in their circle in a clearing by the pond, several in the group heard the distant response of a screech owl -- the only live encounter to be had that night.

“That’s the nature of nature,” said Claus of the Sewickley owls, who retain their mystique, at least until next year.