Fireflies
For many, fireflies are forever linked with summer evenings in childhood memory. Also known as lightning bugs, these glowing insects are neither flies or bugs — they’re beetles (order Coleoptera). And there are many firefly species, including 56 species found in Florida.
The firefly is able to produce bioluminescence — its famous light — with chemicals in its body, luciferin and luciferase. The adults of most species use this light to attract mates. Each species has a different pattern of flashes. But some species do not emit light at all and instead use pheromones to attract mates.
Fireflies start as tiny predators
Female fireflies deposit their eggs in the ground, which is where larvae develop to adulthood. The larvae have three pairs of legs and are rather fearsome-looking creatures with tiny glowing spots on their underside. Researchers have found that all species’ larvae glow, even those who don’t emit light as adults. It’s at this stage that they’re often referred to as glowworms.
Since larvae can’t reproduce, scientists think the bioluminescence is used to warn off potential predators. The larvae of most firefly species are specialized predators and feed on snails, slugs and the larvae of other insects.
The main task of an adult firefly is to reproduce. Fireflies come out at dusk or nightfall in woods or wetlands during the summer. Different species of fireflies prefer different habitats; some spend most of their time in the upper branches of trees, while others live in shrubs, and still other prefer open, grassy areas. Some are coastal; the Florida intertidal firefly (found only in Florida and the Bahamas) inhabits mangroves, salt marshes and tidal mudflats.
How to attract fireflies
Some scientists think fireflies can be deterred by brightly lit urban areas, and that their populations may be decreasing because of mosquito spraying.
To provide habitat for fireflies in your landscape, keep pesticides to a minimum or eliminate altogether. Turn off all of the artificial outdoor lights around the house: flood lights, porch lights, garage lights, and such.
Provide a diversity of habitats to attract a diverse firefly population. Allow edges of your yard to grow up into shrubby areas, or plant vegetation that shades the soil and contributes to preserving soil moisture. Soil moisture encourages the snails, slugs and other insect larvae that firefly larvae eat.
Also on Gardening Solutions
- Beneficial Insects
- Designing a Habitat Garden
- Infographic: How to Attract Fireflies, for Homeowners
- Moonlight Gardens
More from UF/IFAS
- How to Create a Firefly Oasis–UF/IFAS Blogs Polk County
- Night Lights: Entomologist Marc Branham is building on UF’s reputation as a firefly research hotspot–UF Research’s Explore Magazine, Winter 2013
- Planning a Moonlight Garden–UF/IFAS Blogs Indian River County
- Tell Me About Light Pollution–Thompson Earth Systems Institute
- Where to Find Florida Fireflies–UF/IFAS Blogs Polk County
- Some Firefly Natural History (Excerpt)–UF/IFAS Entomology and Nematology (PDF)