Looks like this has be a concern for a few years now DE.......
Recently, an anonymous visitor posted the question, "Why haven't I seen any fireflies over the last few summers?" That got me thinking, and I realized that I haven't seen many fireflies, either. (You don't usually see fireflies in Minnesota until late June or early July, but I don't remember seeing any last year or the year before.) So what's the skinny?
Firefly: Have you seen any of these guys lately?
Firefly: Have you seen any of these guys lately?Courtesy AriCee
I thought about it a little bit.
Like many other insects', fireflies' life cycle includes egg, larval, and adult stages. Adults lay eggs on or just under the soil. Because they eat critters like worms, slugs, and snails, most larvae are found in rotting wood or leaf litter or on the edges of streams and ponds. Adults tend to favor the same habitats as the larvae, but we know a lot less about adult habits. Their mouths suggest that they eat other bugs, and scientists know that some fireflies eat other fireflies, but it's likely that they eat plant nectar and possibly other foods, too. You're likely to see adult fireflies over lawns and meadows and at the edges of woods or streams.
Firefly_larva: Crazy, huh? I know I've never seen these guys around! I'd have made a point of looking them up! (Photo courtesy Myriorama)Courtesy Myriorama
My backyard seems like it would be firefly heaven, and yet I'm not seeing them. What other factors could be at play?
I thought of three. And then I found a fourth possibility on this cool website. (Maybe you can think of others?)
Many areas have stepped up their mosquito control efforts due to concerns about West Nile virus. Is it possible that this has somehow impacted firefly populations? (I think this is an unlikely explanation, because why would we notice a reduction in fireflies but not other insects? And further, there certainly seem to be plenty of mosquitoes!)
Our temperatures have been wacky. Maybe fireflies require a specific temperature range to hatch, or to change from their larval stage to their pupal stage? Are we exceeding that comfort zone, or not staying in the proper range long enough?
Lack of habitat is always a possibility. Maybe they aren't finding enough to eat or the right places to lay their eggs?
Since fireflies communicate with blinking light, perhaps they prefer to inhabit areas away from city centers with all the ambient light that goes along with them? (I think this is unlikely, too, since I've seen fireflies in the city before.)
Or maybe I'm just not looking in the right places at the right times. (Here are a few reported sightings from Minnesota…)
I'm going to do some investigating, talking to some folks at the Warner Nature Center and the University of Minnesota's Entomology Department. I'll post answers as I get them.
But I want to hear from you: have you seen fireflies? Where? Describe the place you saw them. What date? And what time of day?
LOT of comments,,,,,,,,,,,,,,,,,,,,,
http://www.sciencebuzz.org/blog/where-have-all-fireflies-gone

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