Rocky Fork home to both synchronous and blue ghost fireflies

Mackenzie Moore • Jun 21, 2018 at 12:00 AM

FLAG POND — Deep in the wilderness of Rocky Fork State Park lies the habitat of thousands of fireflies. The mating season peak just ended, giving observers a night of fireflies that was anything but dim.

Viewers watched as fireflies both in the air and on the ground flashed concurrently.

“It’s an evolutionary behavior,” Tim Pharis, a park ranger at Rocky Fork State Park, said. “This is all theoretically speaking, but they flash at the same time and then go blank for six seconds. The darkness is more synchronous than the flashing.

“In that darkness, the female responds with two blinks from the ground, sort of to say, ‘Hey, here I am.’ The peak of this behavior lasts around eight days.”

The synchronous fireflies stay hidden in a few isolated areas within the park, generally with cool climates and close to creeks.

“We had one area they were concentrated in, and it looked like something you’d see in a movie,” Marie Rice, the president of Friends of Rocky Fork State Park, said. “I don’t know how to explain it. I really didn’t realize there were that many species of fireflies.

“As far as I know, I think that Rocky Fork is the only state park that we found both the synchronous and blue ghost fireflies.”

Rocky Fork State Park dazzled groups the first two weeks in June with a synchronous firefly show that sold out within minutes.

Friends of Rocky Fork State Park, an organization that strives to preserve, protect and promote the park, hosted its first firefly display to the public, but not everyone could attend.

The group advertised a pre-sale of 200 tickets spanning the course of seven nights — and sold out in less than 10 minutes.

“We posted the ticket sales in advance,” Rice said. “Not really like a lottery like the Smoky Mountains does, but it was more on a first-come-first-serve basis. We ended up selling out within 10 minutes, and I wasn’t expecting such a turnout.”

For those who missed the chance to witness the display, Rice and the organization haven’t ruled out hosting more firefly events for next year, but one thing remains in the board members’ minds that trumps arranging another peak at a natural spectacle.

“We’re mostly concerned about destroying their habitat or eliminating or damaging the fireflies,” Rice said. “We don’t want to get to where we’re harming them. We ask ourselves what the best way is to approach the display so the general public can see the fireflies but not encroach on their territory.”

The Great Smoky Mountains National Park long has been known for being home to a similar spectacle near Elkmont. The annual synchronous displays are so popular that the park must conduct a lottery for visitors to watch, and they must be shuttled to the area where the fireflies are most visible.

And in Pennsylvania, synchronous fireflies light up portions of the Allegheny National Forest, about 100 miles from Pittsburgh, where there is an annual Pennsylvania Firefly Festival. Last year, more than 500 people converged on a local couple’s property for the festival, according to The Associated Press. Campgrounds stay booked for peak firefly season.

Why do these “lightning bugs” blink in synch?

“It’s still a mystery,” Sara Lewis, a biology professor at Tufts University in Massachusetts who has researched fireflies for two decades, told The Associated Press. “Why some, and why not others? Why are they doing it? We still don’t know.”

“It might be the most burning question in firefly biology that we don’t have an answer to,” Lewis said. “Why should thousands of males who normally would be competing for females’ attention, why should they be cooperating?”

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