Blue Ghost Fireflies: Light Show in Tennessee

There’s a lottery for a chance to witness a unique spectacle.

Photo Above: Fireflies light up the night in synchronous display at Rocky Fork State Park in Unicoi County, Tennessee.
Photo Courtesy of Ryan Rice.

Of the 2,200 known firefly species in the world, there is one that is unique to a small region of the Blue Ridge Mountains along the Tennessee-North Carolina border. They are known as blue ghost fireflies. At only around ¼-inch long, they are one of the smallest fireflies in the world. 

They emit a dim white/blue light, and unlike other fireflies they do not flash. They stay lit up for around a minute at a time, slowly swaying back and forth. The females stay in their wingless larval form and light up from the leaves and foliage on the forest floor while the males fly low within a few feet of the ground seeking mates. 

Rocky Fork State Park in Unicoi County, Tennessee, holds an annual lottery in early May to attend viewings of these rare fireflies for three days in late May. The blue ghost fireflies spend the first couple years of their life in larval form and once they mature to adulthood, they are only active for around three weeks in late spring to early summer. During this three-week period they put on an amazing spectacle that is unique in the world of fireflies.

The story above first appeared in our May / June 2025 issue.