Synchronous Fireflies in Great Smoky Mountains June 2024
Synchronous Fireflies in Great Smoky Mountains June 2024. These aren’t your average backyard lightening bugs; these particular bioluminescent beetles (Photinus carolinus) perform an extraordinarily silent symphony of lights in the warm, dark forest evoking images of Shakespeare’s A Midsummer Night’s Dream. It’s truly a sublime experience.
They’ll be here for a week or two in early June 2024. However, the event has become so popular, bringing over 12,000 visitors to Elkmont, that some advance planning is definitely required. Utilizing scientific data on daily temperatures, park scientists have announced that peak viewing time will be June 4 to June 11, 2024. Here are a few tips to help with your planning:
- You can camp at Elkmont and have direct access to the trails where you can view the nightly light show. Campground reservations can be made up to six months in advance at www.recreation.gov. If you want to backpack, backcountry reservations are required and can be made at nps.gov up to 30 days in advance.
- Non-campers have limited to no access to the Elkmont area during the viewing period; however, nightly trolley Shuttles from Sugarlands Visitor Center.
- The Shuttle Operating Dates will be from June 1 to June 10, 2023.
- Visit www.recreation.gov during the specified time period to enter the Lottery. Parking passes may also be obtained by calling 877-444-6777, but National Park officials highly encourage the use of the online process.
- Remember to bring a chair or blanket, rain gear, and a flashlight because it’ll be dark. Keep your flashlight covered with either blue or red cellophane, usually available at the check-in table. Visitors are not allowed to walk the Elkmont entrance road due to safety concerns. For up-to-date info from the National Park Service, please visit GSMNP Firefly Event.
Why synchrony?
Scientists studying the synchronous firefly have determined that the males flash in unison as a way for the female to be certain she is responding to one of her kind. There are other firefly species flashing at night, and some of them are predatory, so she must be able to recognize males of her species.
The flash pattern of Photinus carolinus is a series of 5-8 flashes, followed by a pause of about 8 seconds, and then this pattern is repeated. Initially the flashing appears random, but the period of darkness is synchronized. As more males start joining in, the flashing will also begin to synchronize and entire sections of the forest will be pulsating with light.
Timing of the Display
The mating season of Photinus carolinus lasts for approximately 2-3 weeks each year. The dates that they begin to display varies from year to year based on temperature and soil moisture. We use daily temperatures and predicted temperatures to set the dates of the public viewing event, but any natural phenomenon is highly variable and difficult to predict exactly.