June 27, 2012
14 Fun Facts About Fireflies
Photinus pyralis, a species of firefly found in the eastern United States (via Terry Priest / wikimedia commons)
What’s more magical than a firefly light show on a warm summer night? Just remember that if you catch fireflies, you can keep them in a jar (with a lid punched to let in air and a moistened paper towel on the bottom) for only a day or two before you need to set them free.
(1) There are more than 2,000 species of fireflies, a type of beetle. Despite their name, only some species produce adults that glow. Fireflies in the western United States, for example, lack the ability to produce light.
(2) Males that do glow use their flash to attract females. Each species has its own pattern of light flashing.
(3) In some places at some times, fireflies synchronize their flashing.
(4) Firefly light can be yellow, green or orange.
(5) Firefly larvae may glow, even some that live underground or under water. They use the light to communicate to predators that they aren’t tasty (they produce unpalatable, defensive steroids for protection).
(6) Larvae are carnivorous and particularly enjoy snails. Adult fireflies usually live off of nectar and pollen, but some don’t feed at all.
(7) A few firefly species are also carnivorous as adults. They don’t eat snails, though—they eat fireflies of other genera.
(8) Fireflies are among the many species that are bioluminescent, meaning that they can produce their own light.
(9) A chemical reaction within the firefly’s light organ produces the light—oxygen combines with calcium, adenosine triphosphate (ATP—the energy-carrying molecule of all cells) and a chemical called luciferin, when an enzyme called luciferase is present.
(10) The light is the most efficient light in the world. Nearly 100 One hundred percent of the energy in the chemical reaction is emitted as light.
(11) Luciferase has proven to be a useful chemical in scientific research, food safety testing and forensic tests. It can be used to detect levels of ATP in cells, for example.
(12) When luciferase was first discovered, the only way to obtain the chemical was from fireflies themselves. Today, synthetic luciferase is available, but some companies still harvest fireflies, which may be contributing to their decline.
(13) Other factors that may be contributing to firefly decline include light pollution and habitat destruction—if a field where fireflies live is paved over, the fireflies don’t migrate to another field, they just disappear forever.
(14) Observing fireflies in your backyard can help scientists learn more about these insects and why they’re disappearing.
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We live in a small town in Ontario Canada and when we moved there 10 years ago I was amazed to discover that our backyard “sparkles” with hundreds of fireflies. We have a large lot with lots of bushy plantsthat they seem to love.(peonies, wild flocks)#6 above was interesting as we also have tons of snails due to the peonies and hosta plants.
I remember seeing hundreds of fireflies while walking in Cavendish National Park in Prince Edward Island, Canada. It was an amazing experience, and I’ll have to check it out again this summer to see if it’s changed.
Good on you for attributing that image correctly.
a lovely place to observe fireflies is the pathway along the reflecting pool between the WW2 Memorial and Lincoln Monument in Washington DC. We are from CA and have no glowing fireflies so my kids were quite excited to walk along that path just after sunset…HUNDREDS of fireflies, blinking and glowing! It was SO lovely!!!
This was aninteresting article. For more information Contact Tom Turpin, Entymologist- Purdue Univesity – and a dear friend.
In my country Malaysia,the Kuala Selangor Fireflies is one of the largest colonies of fireflies in the world as the entire area glows with little illuminating fireflies,the rare species that synchronize in unison. As the local Nature Guide https://www.facebook.com/kaynis.chong, taking groups to watch the fireflies dance at night, it is really an amazing memorable experience and sight!
There used to be a lot of them on the Upper West Side of Manhattan, in Riverside Park and the nearby areas. You don’t have to go out to the country to find fireflies.
As a youngster, I caught fireflies for a chemical company. Two out of three years, we caught over 40,000. I enlisted family and neighbors. With a graduated pay scale, once reacing 20,000, we got a penny each. Not bad for an hour and half work for a kid. The fireflies would be put into a paint can along with special moisture absorbing chemicals and the can would be mailed to the chemical company weekly.
Back then, the chemicals could not be synthesized and there was not knowledge on how to raise fireflies (– maybe still lacking on the knowledge). There were plenty of fireflies around 40 years ago, and where I live in SC, there are still a lot.
Some more intersting facts…
a) Fireflies always crawl upwards.
b) Put a jar of fireflies into the refrigerator overnight and they will go to sleep — long enough for you to count them in the morning. (Ccount quickly because they will soon wake up!)
c) A jar of fireflies smells a lot like a cucumber, which may be why I don’t like cucumbers today.
While enjoying a small neighborhood fireworks display,I was watching from a tree-lined field.After each ‘bomb bursting in air’, hundreds of lightning bugs flashed from the trees. It was as if they were competing with the fireworks. Totally delightful!!!
I had guests from Sweden and they were enthralled with the fireflies in my backyard. They said they never saw them in Sweden.
The past two summers we had noticed a sharp decline in the number of fireflies in our yard. We had very mild weather in March this year and starting seeing fireflies then and again in April. Cold weather in May had us wondering how the fireflies would be affected. Now in July we are seeing many more, but still not up the numbers we used to see years ago. Still we’re glad to see the population rebounding somewhat.
Until I moved from Georgia, I saw bouchous of fireflys, “lightning bugs” as they are called in the South, and since a child, have loved to run and catch the flyers, gently, then let them go. Great for eye, hand coordination.
12 years ago I moved to South Carolina, and to my despair found NO lighters! Not one have I seen. I believe it is because I am surrounded by farms, but I lived on a farm in Ga. and there were plenty. We didn’t spray of course. Whatever the reason, I am desperatly trying to find a source of replenishment for the “boogers”. Any ideas? I LOVE, LOVE, LOVE Smithsonian and hope to revisit some day.
I saw lightning bugs in my yard right here in NYC next to Central Park at dusk. I just smiled and stood there enjoying the unusual sight.
One of my favorite memories from my childhood is visiting Aunt Mary in Overton County, TN. She had a huge tree in her front yard. On one warm, soft, magic night I looked up and there were seemingly thousands of fireflys blinking all through it. It’s been 50 years and I remember like it was last night.
I must disagree with fact #1. I live in Colorado, where I have observed fireflies that glow. Specifically in the San Luis valley. This is the only place in Colorado where I have seen them.