There are all kinds of really delightful indicators that a bright, hot Texas summer has arrived: Patio burgers and first swims. Sunsets so late you feel like you’ve gotten away with something. The stars that fly among us.

Fireflies, I mean, or (if you’re wrong) lightning bugs. The light-emitting beetles have been known to captivate Texans as early as April and, depending on weather and rainfall, as late as October. The soothing sight of the little critters, bobbing and glowing through tall grass, often feels as reliable as the changing of the seasons. But some Texans have noticed that this June has seemed dimmer. Right?

Well, maybe not for everyone. Although we might think of and speak about fireflies as though they’re one large conglomerate, there are more than forty different species in Texas alone—and those are just the ones we know about. Ross Winton, an invertebrate biologist with the Texas Parks and Wildlife Department who serves as the organization’s point person for anything without a backbone “except for mussels and crawfish,” doesn’t think it sounds all that unlikely that you yourself could stumble upon a previously unknown variant in your own yard. “When you look at the map of where fireflies appear, there are so many holes and so many unique habitats within those holes. People think you have to go to the upper Amazon or Southeast Asia to find new species, but you can find them in your own backyard,” Winton says. He says this sort of discovery is a fairly regular occurrence with invertebrates, of which there are upward of 80,000 known species just in Texas.

All of that to say, a lot of what determines how twinkly this summer’s looking depends on the health of whichever specific species or population is closest to you. If the kind of firefly that calls your favorite viewing spot home has recently faced any of the most common threats—such as habitat loss or fragmentation by way of development, an increase in light pollution or pesticide use, and extreme weather swings caused by global warming—things might be looking notably dimmer for you this year, too. On the brighter side (wink), this spring’s copious rainfall could lead to a showy firefly season for species that have managed to avoid conventional threats.

If it sounds like there are a lot of unknowns when it comes to where Texas’s firefly population stands across the board, you’re doing a great job of reading this story. “Fireflies have been declining broadly. But across all the species, we really don’t have a grasp to what degree,” Winton says. “Most invertebrates end up in a category that we call ‘data deficient,’ where there’s just not enough data for us to know what’s happening with their population. That’s true for the majority of fireflies in the United States.”

In 2021, the Xerces Society, a nonprofit that works to preserve invertebrate species, and the International Union for Conservation of Nature (IUCN) Red List teamed up to take a sort of firefly census. As painfully adorable as it sounds, the census yielded some discouraging results. The organizations found that 14 percent of all species studied were categorized as threatened, and warned that the number could be misleading and the reality much more dire due to data deficits.

There are a number of reasons researchers are so hard up for invertebrate data. The most obvious is the sheer quantity of species—a plenitude Winton calls “overwhelmingly diverse.” Another reason is general interest. Winton says, for instance, that casual and research-level bird watchers comprise a highly interested, active scientific community. Accordingly, the health and standing of bird species is often thoroughly researched and documented. That same level of interest and “search effort” is harder to achieve for bugs—though, among their insect brethren, fireflies are often regarded by researchers like Winton as one of the more charismatic invertebrates in the state.

“It’s the bioluminescence,” Winton says. “It’s so intriguing. Seeing something glowing on the landscape that is not man-made is not common, so going back hundreds of years there’s references to fireflies.” He estimates there are about a half-dozen firefly researchers in Texas, two of whom will join him this August in West Texas’s Davis Mountains for a pulse check on one of two species in the state that were categorized as threatened in the Xerces Society’s census. “It’s like triage in the ER,” Winton says of the process to label a species as threatened. “We go through this internal prioritization process and ask ‘Which one should we address first?’”

Winton and his fellow researchers will explore the habitat of sky island fireflies, which are currently considered vulnerable by the IUCN. The sky island habitat in the Davis Mountains is threatened by nearby oil and gas extraction development and by drought—something the area has experienced particularly severely in recent years. There’s a chance that, after digging in further, researchers may recommend that the threatened status be removed completely; conversely, they might conclude that the threat is more imminent than was previously thought and the species should be categorized as endangered.

With so many species of fireflies likely facing active and growing threats, and the world of Texas fireflies so vast and still uncharted, the future of nature’s arguably most beloved “fly” (they’re beetles) feels uncertain. But Winton stresses the importance and impact of the microhabitats Texans can host and foster in our own yards and neighborhoods. Plus, you can help contribute data to fill knowledge gaps.

“If you see fireflies or you know an area in your community where fireflies frequent, sharing that on platforms like iNaturalist or the Firefly Atlas is going to be really helpful,” Winton says. “Take a video and share it, if you can.”

How to Lend a Firefly a Hand 

Keep things dark. Avoid using bright outdoor lights after dusk, and if you do need outdoor lighting, be mindful of the colors you opt for and keep them facing downward and toward your house. (This is good advice for keeping skies dark for stargazing, too.)

Avoid pesticide use. Even if you’re using a pesticide that claims to target a certain pest, it will likely have a broader effect on a wide range of species, including fireflies.

Let your yard grow. Fostering an environment where pollinators can prosper will similarly benefit fireflies. Plant native species, mow your lawn infrequently (many firefly species prefer tall grasses), and allow for mixed vegetation.

Contribute data. Like Winton mentioned, recording and posting a short video of a firefly’s flash pattern (which are unique to each species) can help researchers identify and map the creatures.