Fireflies can be found all over the world. But these lightning bugs thrive in warm and humid areas. You can often see fireflies in forests and open fields where there’s water nearby, like a swamp, pond or river.
Seeing fireflies take flight at dusk or dawn is such a magical, enchanting sight. There are over 2,000 species of fireflies and knowing where they live and when to look for them can help you spot these bioluminescent insects.
Fireflies can be found in various climates all over the world, from North and South America to Europe and Asia. Fireflies can also be found in more arid regions, but they typically follow the rainy seasons and congregate around standing water sources. The most diverse firefly populations can be found in tropical Asia and Central and South America, where the climate is wet and humid.
Fun Fact: Almost no firefly species live west of Kansas in the U.S. and we’re not entirely sure why, since there are plenty of warm, humid habitats suitable for them in the western states.
Where do they Live?
Fireflies, which are actually soft-winged beetles, tend to be found near standing water and can live in forests or wooded areas as well as open fields. You might also find fireflies in areas with long grass or bushes where they will sleep during the day. Fireflies tend to stick to areas that retain water, so even drier areas can host them as long as there is a water source, like a pond, swamp or lake.
It’s believed that fireflies thrive in wet or damp areas because of the presence of other insects, which they feed on. Female fireflies will lay eggs in the ground. When they hatch, the larvae, also known as glow worms, will feed on ground insects until maturity. Their prey include worms and slugs, which the larvae inject with a numbing fluid before feeding.
How do Fireflies Glow?
Fireflies produce an enzyme called luciferin inside dedicated light organs in their abdomens. Oxygen is taken in and light is produced with almost no heat, creating their signature bioluminescence. The glow that fireflies produce is intermittent, so it looks like they are twinkling in the night sky. And if you pay attention you can identify fireflies by their flashing patterns.
Why do Fireflies Glow?
This flashing behavior does not occur randomly and flashing patterns are unique to each species. Entymologists believe that fireflies may be able to regulate the amount of oxygen being sent to their light organs and this may be how they turn their glow on and off, but we’re still note entirely sure. What is believed though, is that flashing serves several purposes, including finding a mate and warning off predators.
For Mating
While there are a few species of day-flying fireflies that don’t produce light at all, many species use their bioluminescence to signal potential mates. The male firefly will take flight and begin his light display, while female fireflies will watch from the ground. If a female firefly sees a signal specific to her species that she likes, she will respond by displaying the same light pattern.
This usually signals the start of their mating ritual and the fireflies will continue to signal to each other as the male makes his way to the female. Think of it as a the mating version of Marco Polo. For those species of firefly that don’t light up, pheromones take the place of flashing to attract a mate.
For Warning off Predators
Fireflies also glow to warn predators not to eat them. The enzymes they produce, not only glow, but taste bad, which makes them less appetizing to other predators. And it’s not just the adults that produce a foul-tasting glow — larvae also glow, supporting the belief that their bioluminescence also serves as a defense mechanism. Some fireflies are also poisonous to lizards, birds and frogs — and you shouldn’t try eating them either.
What do Fireflies Eat?
Firefly larvae are carnivorous and since they live on the ground for one or two years until maturation, they usually feed on earthworms, slugs, and snails and might also eat the larvae of other small insects. This makes firefly larvae great for your garden, but as adults, their diets change.
Adult fireflies feed on the nectar and pollen of plants and some may not eat at all, since their lifespan is only a few weeks as adults. But while they’re here, if they do feed, they’re great pollinators. Adults have a lifespan of 3 to 4 weeks, just long enough to mate lay eggs.
Where to see Fireflies
Unfortunately, if you live in the city, even in a state that has a warm or humid climate, you’ll need to venture out a bit to see them. Light pollution in the city makes it more difficult for firefly mating rituals because bright city lights can prevent female fireflies from seeing the males’ signals.
Instead, look for more rural areas that have wide, open fields and no light pollution and set up a blanket to sit on while you wait. You might also be able to see them in national parks. Because these areas are secluded they can be darker, making it easier to see them.
If you live in a suburban area with a known firefly population, you might be lucky enough to see these glowing insects in your backyard. If you want to attract fireflies to your property, though, you should make it as firefly-friendly as possible.
Try avoiding pesticides, turning off lights at night, and installing a water feature with adequate vegetation. Since you don’t want your garden to be overgrown, you can designate one small patch as the fireflies’ habitat by keeping the grass long and avoiding cutting down the trees in that area.
Summer nights can instantly turn magical if you’re lucky enough to spot them, especially as they twinkle against the darkness of the night sky. Now that you know where they live, and how they behave, you’re in a much better position to enjoy them while they’re here.