Trek to the Pennsylvania wilds this summer to admire rare synchronous fireflies

“It’s like natural fireworks.”

Fireflies streak across the sky, as if in competition with the stars above.

Fireflies streak across the sky, as if in competition with the stars above.

Courtesy of the Pennsylvania Firefly Festival / Photo by Ian Toole
Rossilynne Culgan

Updated 11:15 a.m. May 18

A few hours northeast of Pittsburgh, deep in the darkness of the Allegheny National Forest exists a place where the glow of fireflies takes center stage for a magical, bioluminescent performance.

There, more than 15 species of firefly swarm the skies, including the highly sought-after “synchronous firefly,” which blinks in unison, seeming to punctuate silent sentences that humans can’t translate.

“It looks like a huge wave of light coming through the forest. One will start and then the other ones will join in. Sometimes they seem to be answering each other across a path or across a creek,” said Peggy Butler, secretary of the Pennsylvania Firefly Festival. “When people see it, they’re just in awe. It’s like natural fireworks popping off.”

Fireflies crowd along the banks of Kelletville Creek.

Fireflies crowd along the banks of Kelletville Creek.

Courtesy of the Pennsylvania Firefly Festival / Photo by Justin Jones

If you’re up for a drive and a bit of adventure, you can spend an evening among the fascinating creatures at one of the Pennsylvania Firefly Festival’s events this summer. There are few options for firefly spectators on June 8, 9, 15 or 16, leading up to the grand finale Firefly Festival on June 23. Book in advance for a guided creek excursion or a special viewing of synchronous lightning bugs. General admission is just $5, but tickets are limited and are going fast.

This is the sixth year for the Pennsylvania Firefly Festival, which began almost by accident. In 2012, scientists from Firefly International Research & Education spent the night at Peggy and Ken Butler’s Black Caddis Ranch investigating a tip that the extraordinary synchronous firefly found in the Great Smoky Mountains might exist in the Tionesta area. Through research and DNA analysis, they confirmed their hunch — and told the Butlers to brace for the impact of increased tourism.

The Butlers pulled together a group of volunteers to form the Pennsylvania Firefly Festival, and it immediately drew hundreds to admire Pennsylvania’s state insect. The annual festival attracts people from Pittsburgh, of course, and from as far away as Asia and Europe.

While increased tourism is welcome, it also means volunteers must manage the crowds to protect the fireflies, which are “fragile” creatures, Butler said.

Fireflies start to appear around mid-to-late June, and the synchronous pattern is specific to males.

“The whole purpose of this season and the displays of the males is to attract the females and to mate,” Butler said, adding that there are about 300 males to every one female. “Competition is very high and very heated. That’s why you get these amazing displays from these tiny creatures.”

The exact reason for their simultaneous flash remains a mystery, according to the National Park Service. Perhaps, the park service suggests, males want to be the first to flash, or maybe they blink together to give the females an opportunity to make comparisons.

Synchronous fireflies blink in unison.

Synchronous fireflies blink in unison.

Courtesy of the Pennsylvania Firefly Festival

If you go, expect a late night and be prepared that there’s no refund if rainy weather dampens the fireflies’ performance, Butler said. And, she warns, keep in mind this truly is a trek in the wilderness — bring extra water, dress properly, fill your car’s gas tank in advance, and make plans to stay overnight.

“You have to be out there in the dark, and for city dwellers that’s kind of hard sometimes,” Butler said.

While it is an excursion, it’s also a time to learn about how to help these fascinating creatures, which call Pittsburgh home, too, not just the national forest.

“The major significance of fireflies is as an indicator species. They indicate that the environment is healthy — free from pesticides, light pollution, water pollution,” Butler said. “If you don’t see fireflies in your yard or your neighborhood, there’s a reason — you need to pay attention to that. They should be there.”

Correction: Ken Butler’s name has been corrected.