Chasing after the blinking glow of fireflies on a warm, summer evening is a favorite childhood memory for many Hoosiers. Unfortunately we may be chasing after fewer and fewer of these magical insects this summer. Populations are dwindling all over the country and throughout the world.
Fireflies, also known as lightening bugs or glow worms, are winged beetles known for their use of bioluminescence in the twilight hours. Bioluminescence is a type of chemical reaction that allows fireflies to produce a cold light, meaning it emits little to no heat. The chemical reaction is usually produced in the light-emitting, lower abdomen. The light may be yellow, green or pale red depending on the thousands of different firefly species across temperate and tropical environments. Larvae of all species glow, and some also have glowing eggs. However, not all adult fireflies twinkle at dusk or dawn.
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Fireflies glow as a way to communicate with potential mates as well as predators. When attracting a mate, it all comes down to how it twinkles. Every species of firefly has its own distinct pattern of flashing their light-producing bottoms. Males and females of the same species will flash this pattern to let each other know of their presence.
When it comes to predators, fireflies glow as warning to stay away. Most species of fireflies are filled with a nasty tasting chemical. Those who have had a mouthful of this chemical quickly learn to associate the firefly’s attractive glow with a very bad taste.
Have You Noticed Fireflies Less?
So are fireflies disappearing? Scientists and researchers aren’t sure, but most believe that development and light pollution are driving them away. Most species of fireflies are born and thrive in the rotting wood and understory of forests near lakes and ponds. As they grow, they tend to stay near where they are born. As more forests and open fields continue to be developed, their habitat becomes threatened. Homes and businesses that are built around our waters also distract and deter fireflies from living in that area.
Scientists can't be certain, but light pollution - the excessive and obtrusive use of artificial light -seems to drive firefly populations down. As we learned before, fireflies use their bioluminescence to communicate with one another as a way to attract mates. If there is too much light surrounding their habitat, there is a chance that males and females won't be able to mate. Less mating means fewer fireflies which means fewer chances for future generations to know the joy of watching and chasing fireflies on a warm, summer evening.
How You Can Help
The Museum of Science in Boston, Massachusetts is asking the public for their help in recording the number of times they see fireflies during the summer season. With your help, the Museum of Science as well as their partners, Tufts University and Fitchburg State College, hope to learn about the geographic distribution and activity of fireflies. Learn more about the Firefly Watch and sign up to participate today.