Some Simple Steps to Attract More Lightning Bugs to Your Property

Have you noticed a decline in the number of lightning bugs? Lots of folks seem to remember seeing a lot more of them years ago.

This week I spoke with Ben Pfeiffer, founder of the nonprofit Firefly Conservation and Research. We discussed the decline in lightning bugs (also known as fireflies). Pfeiffer offered advice to gardeners and property owners about attracting lightning bugs and improving their habitat.

But first of all, what do you call them – lightning bugs or fireflies? They refer to the same family of insects known as Lampyridae. Pfeiffer said the term “lightning bug” tends to be more prevalent in the southeastern United States, with “fireflies” more common in the other parts of the country. Texas falls somewhere in between, and both terms are commonly used here.

Pfeiffer said he’s been interested in the flashing bugs from a young age.

“I’m a native Texan, sixth generation, and been here a long time,” he said. “I grew up in the Hill Country and South Texas. I spend a lot of time outdoors, and just love everything about Texas ecology and nature.”

Pfeiffer studied biology at Texas State, but then launched an internet company after graduation.

“It’s funny how that works out,” he said.

But while in college, he visited a bioluminescence lagoon in Puerto Rico.

“They have these freshwater lagoons, and in those lagoons, they have these bioluminescent organisms that light up when they’re disturbed,” he said. “It piqued my interest in bioluminescence, why this happens. It’s such a unique thing in the animal kingdom.”

Then in 2009, as a New Year’s Resolution, he started the website firefly.org. He started publishing information about firefly decline.

“At that time it was really early – no one had really heard of it,” he said. “There had been incidental reports of fireflies declining.”

Pfeiffer started publishing information about the various species of fireflies in Texas. That effort morphed into the nonprofit he now runs, Firefly Conservation and Research. He’s now a noted expert on fireflies and often speaks on the topic at conferences and events.

Pfeiffer said land development and light pollution are the biggest causes of firefly decline. Land developers often scrape the surface and completely remove vegetation to make way for construction. Firefly larvae live in the soil and feed on microorganisms. Drastic changes in land use destroy their habitat. Pfeiffer said development along riparian areas such as creeks and river bottoms are especially harmful to fireflies. This has been a major problem in the Austin area, he said.

Light pollution also drives fireflies away.

“Flashing in fireflies originally came about as a signal to warn predators that they are poisonous,” Pfeiffer said. “This was originally how the light signal developed millions of years ago. Then it became a form of sexual communication between males and females.”

The different species of fireflies exhibit different flashing patterns. In fact, that’s one of the primary ways to identify the specific species of fireflies. Fireflies use these flashing patterns to find suitable mates.

“It allows each species to find each other at night,” he said.

However, fireflies cannot see each others’ flashes when light pollution floods the night sky.

So what can people do to help fireflies?

“Gardeners are really good friends of fireflies,” Pfeiffer said. “The reason is because they usually make environments that are really rich, the soil is very rich. That attracts the food for fireflies – small native earthworms and small snails that the larvae eat. People can improve the native habitat that they have or the garden they have by making amendments to the soil, introducing nutrients. Really what you’re trying to do is attract females to lay eggs where you’re at.”

Heavy, woody mulch layers prevent females from laying eggs in the soil. Accordingly, Pfeiffer recommends against applying heavy mulch under tree canopies - an important habitat for fireflies.

He said large expanses of lawn grass aren’t the best habitat, either.

“Old men need to find better hobbies than mowing the grass,” he joked.

Landowners with small acreage should consider converting some of their mowed areas into gardens or natural prairie-type habitat.

Pfeiffer said landowners can also try to eliminate light pollution such as flood lights. Where lighting is needed, Pfeiffer suggests installing downward-facing lights. LED lighting, he said, is especially harmful for fireflies. Bluish light blinds the fireflies more than amber or red-colored light.

“No light is the best,” Pfeiffer said. “Red light is the least harmful. Second best is amber lighting.”

Pfeiffer’s website firefly. org offers a wealth of information about identifying the different species of fireflies and improving their habitat. His nonprofit Firefly Conservation and Research also offers a Firefly Habitat Certification program. The program financially supports efforts of the nonprofit and provides landowners with the best practices for improving firefly habitat.