Synchronous Fireflies Event in the Great Smoky Mountains

By Pamela Blauvelt

We spent a magical night among the fairies in one of the most beautiful spots on Earth.  What’s even better is that those twinkling lights were thousands and thousands of bugs!  We spent a night in absolute darkness in the forest with a bunch of strangers to get a glimpse of some bugs.  Crazy, maybe.  Worth it, absolutely.

This past June, Mary Vongas of ChemTec Pest Control, NJ and Eva Spencer and Pamela Blauvelt with Griffin Pest Solutions, Michigan were the lucky trio who got to spend a girl’s trip out at the synchronous firefly event in the Great Smoky Mountains.  This annual event is on most entomologist’s (and pest management professional’s) bucket-list, the show is a beautiful example of just how unusual insect dating and mating rituals can get.

Located in a small section of our most visited national park, the Great Smoky Mountains, the annual synchronous firefly event is the 2-week mating season for the Photinus carilonus, America’s only species of firefly capable of synchronizing their lighting display.  Their mating season usually begins by late May and ends in early June, although this varies with temperature, weather, and rainfall. 

The males of these tiny, flying fireflies, sometimes regionally known as lightning bugs, light up or “flash” their abdomens at females to attract a mate.  It’s this lighting pattern that makes the fireflies at the event so famous.

Instead of the random, flash-at-will pattern common in most all other firefly species, the male Photinus carilonus has been flash mobbing potential girlfriends for thousands of years.  The males time or synchronize their flashes together as a mass, all going off together for a few twinkling seconds, then all going dark for a few moments.  This pattern repeats all through the dusk and early night hours.  Throughout the woods and across the park, from a height ranging from 2 feet off the ground to 8 to 10 feet above the forest floor, these fireflies spread out, twinkling like moving strands of Christmas lights, threaded through the trees, brush, and even over rivers and ponds.

The females stay on or close to the ground during this display, responding with a quick double-flash as a response to the males.

Scattered throughout this display, you’ll also get glimpses of the 18 other firefly species located within the park, one of note, a deadly copycat species that mimics the synchronous firefly’s flashes to lure in a mate only to consume them.

Watching this display with the other visitors, young and old, from as close as Pigeon Forge to as far away as Osaka, Japan, in the dark in the coolness of an early summer night, is truly a back-to-nature experience and well worth the multiple years spent entering (and losing) the lottery for a coveted spot on the shuttle buses.

Every year, around late April, the National Parks Service announces the dates for the lottery to the synchronous firefly event.  In 2018, the park received 22,000 applications for the coveted 1,800 parking passes. Each parking pass is good for one vehicle with up to six firefly enthusiasts.  Lottery winners and their scheduled view dates are announced during the second week of May. Costs are minimal, $2.00 per shuttle passenger and a $20 reservation fee.  Applying for the lottery is free. When the day of your pass arrives, you pull into the Sugarland Visitor Center before 7 pm and get in line for a shuttle.  The park is good about giving you advance notice of what to bring and how to prepare for the night.

We spoke with many steadfast lottery applicants who waited more than five years to be selected. If you’re one of the lucky lottery winners, our best advice is to share the experience with family and friends, meet a few new friends on the way, and when the show starts, just sit back, relax, and take in the magic.