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Synchronous Fireflies in Pennsylvania are Rare and Unusual

By Bruce Parkhurst

Imagine being in the Allegheny National Forest on a warm June evening around 10 p.m. The campfire has burned low and the upward-floating sparks are subsiding, when suddenly you catch sight of a pulsing flash deep in the woods.

Bruce Parkhurst

As your eyes adjust to the darkness, you see more tiny lights flashing and their momentum gathers. Flash, flash, flash. Then the lights go out and it’s pitch dark again.

Moments later, there’s a sudden burst of lights, as if all of them are controlled by a single switch, and again the rhythmic pattern of flash-flash-flash-darkness.

You’ve just witnessed the annual mating dance of the synchronous firefly known as Photinus carolinus.

The discovery of synchronous fireflies in western Pennsylvania caught the interest of a team of scientists from the Firefly International Research & Education (FIRE) Team, who arrived on the scene in 2012 to confirm the sightings. The five-member FIRE Team, led by Dr. Lynn Faust, collaborated previously on studies of firefly populations in the Great Smoky Mountains National Park, one of the few known locations for synchronous fireflies outside of Southeast Asia.

This short video contains footage of synchronous fireflies in the Great Smoky Mountains:

This time during their 12-day search in Pennsylvania, they found a “robust and widespread” population of Photinus carolinus in Forest and Warren counties, plus more than 15 different firefly species, including the firefly Photuris pennsylvanica, which has served as the official insect of the commonwealth since 1974.

What started in 2011 as the astute nighttime observation of a camper with an appreciation for the wild and natural beauty of the Allegheny National Forest has sparked the local community to organize an annual festival celebrating the beetle. The Second Annual Pennsylvania Firefly Festival (PAFF) will take place on Saturday, June 28, 2014, from noon to midnight, in Kellettville, Forest County, PA.

If this sparks your interest, why not get involved? The inaugural 2013 PAFF attracted an intrepid group of interns, graduate students, and the staff of Allegany State Park in neighboring New York to assist with education outreach.

This year, PAFF extends its call for volunteers as word spreads about the rare and unusual synchronous fireflies and other species. PAFF welcomes science-minded individuals to help with the science education side of the event. This includes talking with kids about fireflies during the day, leading hands-on activities such as insect catch-and-releases, or giving fireside talks to groups whom local residents will lead on walks to observe the two most dramatic flashing species — Photinus carolinus and another in the genus Photuris known as a Chinese lantern.

Opportunities to serve as educational exhibitors are also open to all at no cost, which is perfect for those who know the value of grassroots science education. Plus, there will be live music, food, and a beautiful place to spend the day.

For more information about the festival or about participating as an exhibitor or volunteer, please visit the website, or find us on Facebook. We also welcome and train monitors to log firefly activity as we participate in the Boston Museum of Science firefly data project.

We welcome anyone who would like to join in the effort to give a memorable experience to visitors, and to help bring attention to these remarkable beetles. Please contact Bruce Parkhurst at, or Peggy Butler at for more information.

Read more at:

Allegheny National Forest 2012 Firefly Survey, Forest and Warren Counties, PA

VIDEO: Synchronous Firefly Display Brings Visitors to Elkmont


Bruce Parkhurst lives at the edge of the Allegheny National Forest, manages the local farmers market in Tionesta, serves on the board of the PA Firefly Festival, and is on the advisory board of the Penn State University Agricultural Extension. She holds a master’s degree in Remote Sensing & Geographical Information Systems (GIS) from the Center for Energy & Environmental Studies at Boston University, and a B.A. in French, also from Boston University. She has always loved fireflies.


  1. I just discovered that I have synchronous fireflies on my land just outside Ebensburg, PA! What an amazing display!

    • They are reported to be in Portersville, PA. I saw swarms of them coming back from my first Firefly Festival in Kelletteville, Forest County PA. It was definitely them, they were blowing up along the shoulder of 79 south by Portersville exit. I guess they aren’t as rare as they are said to be, but still awesome! And Philly ain’t got em!!

      • Hello Mike!

        A great place to register your observations is at the Boston Museum of Science (MOS) Firefly Watch. Our PA Firefly Festival group takes part in the study, and registered a lot of attendees at the MOS site during the festival. I’m sure they’d appreciate your observations.

        Thanks for your interest. Who isn’t enchanted by fireflies?

    • Hello Rod R!

      Your obersvations are appreciated – entomologists suggest that the synchronous firefly Photinus carolinus can be found throughout the Allegheny National Forest area, and there is certainly anecdotal evidence aplenty.

      Their display seemed especially intense this year. After the winter we had, no wonder we aren’t all flashing synchronously!

      You might consider registering at the Boston Museum Firefly Watch project, where citizen observation data can be logged. You can find them at

      Their lives as adults are short but the fireflies make the most of it. We could all learn from this little beetle.

  2. We live just north of Huntingdon PA have been here 12 years and last year we got to see them right across from our house so when June rolled around this year we started to watch for them and sure enough last few nights week of 20th through 25 they have been out , the most spectacular thing to watch hope there out again tonight

  3. My wife and I were camping in Bucks County PA close to the Delaware River. While enjoying a campfire and the Steelers preseason game against the Saints on 8/19/2016, my wife noticed hundreds of fireflies lighting up only a few yards from us. They moved as a group to our right and then back to the left. It was amazing.

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