It’s been a summertime tradition for generations.
You sit on the porch in the backyard, or maybe in a lawn chair, or maybe you just stand and wait as the night comes. You see one flash. Then another. And then another, before – voilÀ! – the night is awash in little yellow and orange flashes of light.
Only, these days some people say they’re seeing this less and less.
Which has many pondering: Where are all the fireflies?
I’ve had people come up to me and tell me, We used to see them all the time as kids, but I haven’t seen one in a long time,’ says Don Salvatore, a scientist and educator at the Museum of Science in Boston.
Researchers like Salvatore for years have heard talk like this. There aren’t as many fireflies as there used to be, people don’t see them that much, not like when they were kids. But it’s only been in the past few years that scientists have begun any kind of attempt to figure out the firefly population.
And their conclusions?
So far, there are none – at least definitively.
Are fireflies declining? It’s not a fair question, said Tom Turpin, an entomology professor at Purdue University, who noted there are roughly 30 species of the affectionately called lightning bug found in Indiana. Some species may be; some may be not.
We ask people who ask that, What’s your basis for comparison?’ he continued. Did you grow up in a rural area but now live in a city? How often do you go outside in your yard in the evening? As often as you did as a kid?
The evidence firefly populations may be declining is anecdotal at best, but Turpin did note that there is a good possibility the insects are disappearing. And there are several theories as to why.
Fireflies feed on slugs and as cities expand, water areas have been drained, destroying the insects’ habitats. No slugs means no food.
Also, fireflies use their flashes as mating calls. Expanding cities and more buildings in rural areas – such as airports – means more light pollution. More light pollution means fewer fireflies are finding mates.
Add to those pesticides, which may not carry as much impact as the first two but still may play a part, Turpin said.
While no significant research exists on firefly populations, there are researchers like Salvatore who are trying to gather the best data they can.
In 2008, Salvatore and others at the Museum of Science created Firefly Watch, a community project that has enlisted the help from citizens all over the country in trying to decipher whether that insect population is indeed dwindling.
So far, 64 families spread throughout Indiana have volunteered to participate in the project, Salvatore said. Unfortunately, observations have not been conclusive as to how the bug is faring – here or elsewhere.
What we’ve found so far is that the numbers vary widely from year to year, Salvatore said. Some years have been very, very good. Other years have been bad years.
We only have seven years of data, he said. We need a lot more.
How the project works goes like this:
People sign up and agree to observe fireflies in their backyard. They give the researchers a detailed description of the environment, i.e., is it near water? Are pesticides present? Is it rural or urban?
Then, the volunteers will on certain nights go out to their backyard and observe fireflies for 10 seconds. They then report roughly how many fireflies they think they saw. Zero to five? Six to 20? Over 20?
Researchers aren’t looking for exact counts. If you see 100, you’d tell them more than 20, Salvatore said.
According to the data on the Museum of Science’s website, some of the field notes from volunteers in Indiana – who are not identified – range from the sad to the optimistic, like most parts of the country.
Lots of fireflies tonight! wrote one observer from Fort Wayne in August 2009. I saw about 15 or so in my immediate backyard that’s on the wood line. If I were observing into the woods and keeping numbers there would have been many, many more counted.
One night in June 2010, someone in the city reported more than 20 in the night sky right before a thunderstorm swept through the area. The following month observers in Fort Wayne saw between six and 20 fireflies.
No fireflies yet, wrote one person from Fort Wayne during May in 2011. The doggies and I await patiently.
The last observations of fireflies in Fort Wayne for the project date back to 2012, in which the observer saw none during the night of July 16. Observers in Carmel, though, saw many earlier this summer.
We had heavy rain and strong winds and after the storm the fireflies came out almost immediately, wrote the observer in June. I’m thinking to dry off their wings as well as looking for mates.
The observer in Carmel saw no fireflies last month.
On his farm in Lafayette, Turpin said he has seen an unusually large number of big dipper fireflies for this late in the summer. The big dippers are the most commonly found species of fireflies in North America, and Turpin said they’ve been all over the place where he lives.
Researchers at Clemson University have also started their own project similar to the Firefly Watch. Dubbed the Vanishing Firefly Project and also enlisting help from normal, everyday citizens and using tactics much like Firefly Watch, results for this year show firefly populations to be in the 51 to 100 bugs-per-count range in areas near Indiana.
The loss of fireflies will affect the environment that much, according to Turpin, unless you hate having slugs around. Still, fireflies are popular with generations of people, and trying to decipher populations, researchers said, also provides a teaching opportunity for kids along with an activity for the family.
I tell people, if all the crane flies disappeared, would you notice? Salvatore said. What do you think the first response to that always is? It’s, What’s a crane fly?’
But if all the fireflies disappear, and you love to see them and want to show them to your kids, you’re going to notice, he continued.
So the research continues, with the hopes that the light of what has been a summertime tradition is not dimming.
At least anytime soon.