SACHA PFEIFFER, HOST:
Fireflies can make a walk on a summer night seem magical. But in some parts of the country, those blinking lights in the sky have dwindled.
DARIN MCNEIL: Maybe you see 10. Maybe you see five. Maybe you see zero. All of that information is super valuable for researchers like myself to conduct studies like the one that we did.
MICHEL MARTIN, HOST:
Darin McNeil of the University of Kentucky co-authored a study on the U.S. firefly population. It turns out the number of fireflies you see depends on two important factors.
MCNEIL: Weather and climate variables, especially things related to how hot the summers are and how warm the winters are, are some of the most important drivers of firefly abundance.
PFEIFFER: McNeil examined data from 24,000 surveys of firefly activity conducted by lightning bug lovers across the country.
MCNEIL: So if you have a bad year for fireflies, it may not actually be because of what's happening in that year. It may be because of what happened last year or the year before or both.
MARTIN: McNeil says this kind of research is not possible without citizen scientists. All you need is your phone to report the number of fireflies you see.
PFEIFFER: And here are some tips for making your yard firefly friendly. McNeil says it starts with outside lights. Artificial lights can disrupt fireflies' ability to reproduce, so turn them off.
MARTIN: Next, take a look at the garden or plants outside.
MCNEIL: If you you have gardens, leaving some of that natural leaf litter, leaving access to the soil, not having a perfectly sterilized yard can be really helpful for supporting fireflies.
MARTIN: McNeil follows his own advice, and he says his backyard now has a free light show every night.
(SOUNDBITE OF SONG, "FIREFLIES")
OWL CITY: You would not believe your eyes if 10 million fireflies lit up the world as... Transcript provided by NPR, Copyright NPR.
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