No Georgia resident’s childhood is complete without a memory of catching fireflies. I remember as a child when the heat of the summer would first arrive, sending me and my friends outdoors at the sight of the small, twinkling beetles that lit up the evening. Excitedly, we would capture the small lightning bugs in our palms and watch them glow in search of a mate that waited below in the grass. Photinus pyralis, or the eastern firefly (also known as the Big Dipper), is the most common firefly in the Eastern US. Its yellow, J-shaped flash is all too familiar to many. Another well known is the Blue Ghost firefly that resides in the Southern Appalachian mountains, showing off its continuous blue-white radiance. It was believed during the Civil War that these lights were the ghosts of soldiers wandering in the mountains.

Big Dipper firefly licensed under CC BY-SA 2.0

Fireflies are unique in that they are bioluminescent, meaning that they can create their own light, much like an angular fish in the deep ocean. New research shows that they may be able to change their colors as well. They are also amazing insects because they hold a significance to many people that grew up loving their presence alongside the forests of Georgia. As I grew older, I thought my life getting busier prevented me from seeing these fireflies much as I used to. In actuality, their numbers have been declining in recent years.

Glow of Blue Ghost fireflies. Image by Spencer Black

Unfortunately, their populations are steadily decreasing, thanks in part to growing urban areas and light pollution. When night skies are lit up and forests are no longer dark in the evenings, it makes it incredibly difficult for fireflies to see each other’s glow, a sign that they are looking for mates. Combined with deforestation and certain land management practices, fireflies living in urbanized places like Atlanta can be hit the hardest as their habitats are disappearing.

Last summer, I interned with EcoReach, an environmental outreach program, and helped work on the Atlanta Firefly Project. The Atlanta Firefly Project was first founded by Kelly Ridenhour for her master’s thesis at UGA as she studied the effects of urban areas on these fireflies. After she graduated, EcoReach took over the next summer in 2022. The project’s main goal is recruiting volunteers in the Atlanta and Athens region to record data about the number of fireflies around their own residence. Combined with information about the amount of greenspace in the area, the use of insecticide, outdoor lighting at night, etc. we managed to find evidence on what can increase or decrease firefly abundance.

Fireflies in Georgia licensed under CC BY-SA 4.0

High rates of healthy vegetation is correlated with an increase of flash counts. Use of mosquito repellant, turning on outdoor lighting at night, irrigation, and removing leaf litter can all lead to a negative effect on firefly abundance, especially if these practices have been in place for years. Mosquito repellant can have chemicals that are also damaging to fireflies, turning on outdoor lighting during spring and summer evenings where these lightning bugs go out to mate can disorient them, and removing leaf litter takes away a habitat for their larvae. Being conscious of what can and cannot hurt fireflies is vital to keeping them around. Since cities are only growing, it’s increasingly important to mitigate these harmful effects. People who live in urban areas still deserve to see the magic of fireflies.

If you love to learn more about fireflies and how you can help in their conservation, you can visit the Atlanta Firefly Project’s website, atlantafireflyproject.org, or the Xerces Society’s at xerces.org for more information.

Atlanta Firefly Project Logo