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The Flight of the Texas Fireflies

Published Monday, May 20, 2019 1:00pm

Although they’re on the rebound in Central Texas, these magical flying beetles aren’t lighting up the sky like they used to. A New Braunfels expert says they’re still out there if you know where to look.


“Here come real stars to fill the upper skies,
And here on earth come emulating flies,
That though they never equal stars in size,
(And they were never really stars at heart)
Achieve at times a very star-like start.
Only, of course, they can’t sustain the part.”
―Robert Frost

In a state with more than its share of biting, stinging, and creeping and crawling insects and arachnids with little or no charm to any but their own species, fireflies (or lightning bugs as they are variously known here) have long enjoyed a special place in our hearts, that rarest of varmints—a charismatic insect.

To those of us who grew up in suburbia or out in the country in recent decades (or those who grew up in big cities long ago), they remind us of carefree evenings in the spring, twinkling original-recipe-flavored-Gatorade-yellow-green galaxies wafting on warm breezes over grassy lawns or scraggly brush.

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Industrialization hasn’t been kind to the flying luminescent beetles. My father grew up in the Houston enclave of West University Place in the forties and fifties and recalls seeing plenty of them in his backyard in those days. Today, they are so scarce in the Houston area that one local naturalist has suggested turning a strip of brush along a bike trail near a hidden-away park in the Heights area into an eco-destination, a companion to Houston’s Waugh Drive Bat Colony.

“There are fireflies in Houston, but they are not as prevalent as they once were, and the species diversity is pretty flat,” says Ben Pfeiffer, a New Braunfels-based firefly researcher and naturalist. “There is really no native habitat left in Houston for any of the unique species, so what you find in Houston is just the common type of firefly—Photinus pyralis. You might find some other [types] hidden away in pocket parks and stuff like that, and the hurricanes have helped fireflies out a lot—kinda cleaned out some areas and let them repopulate in some areas because it might have been too dry or overpopulated with people.”

Theories abound as to why why American firefly populations have been in decline in recent decades; mosquito sprays, ravenous fire ants, and light pollution are three possibilities as to why nights in central Houston and the Big D no longer flicker like they once did. But because lightning bugs are known to exist and even flourish in areas where some or all of those factors are at play, each theory, on its own, is insufficient.

It seems that something like “habitat destruction—unspecified” will have to suffice for now. While they can withstand fire ants, mosquito toxins, and light pollution, perhaps it’s just that they can’t handle not all three and the wholesale paving over and/or manicuring of the grassy fields and the well-watered woodland edges they favor.

“Firefly diversity is only as good as firefly habitat, so if you’ve got low-quality habitat, you’ve got low-quality diversity,” Pfeiffer says. The greatest variety of fireflies lies to the west of Houston and Dallas and the Davy Crockett and Sam Houston national forests, where in terms of eco-regions, the Deep South peters out and the American West begins, he says. “The Hill Country is unique. And you’ve got the prairies, and South Texas, which blends with Mexico, so you’ve got all these species that don’t occur anywhere else in the country. So that makes Texas a really, really cool place to study. Even the stuff you see in North Texas is different than the stuff you see down here, and the stuff you see in West Texas is really interesting.”

There is not nor has there ever been a firefly census of Texas, so we have to rely on anecdotes and scattered reports to give us an overall assessment of their status. While the reports that you do hear about them tend toward the grim, Pfeiffer doesn’t believe that any of Texas’s astounding varieties of firefly species are on the verge of outright extinction; in fact, populations in Austin and the entire Central Texas area have been on the upswing in recent years. Pfeiffer recalls that fireflies were nearly absent from CenTex twilight skies after the scorching drought of 2011, which for lightning bugs as with so many other Texas creatures, was a calamitous catastrophe. “I’d go out looking for them and see one or two flashes in a whole night,” he says. Thanks to steady, abundant, and well-timed rains since then, they have returned with a … well, “a vengeance” doesn’t seem right when you’re talking about fireflies. How about a constellation? Whatever the word, beginning in 2013 reports started coming in from San Antonio, Austin, and the Hill Country declaring that the flying beetles were once more out in numbers, putting on their little light show after the sun had set and before the stars had yet to burn bright.

Pfeiffer adds that in some cases, we are simply blind to what’s out there.

“Fireflies are doing really well in some areas and not in others, and a lot of it has to do with how much residential development is going on in really beautiful areas,” says Pfeiffer. As a native of Fredericksburg who has called New Braunfels home for the past twelve years, he should know. “It’s no wonder that humans want to live along rivers and in areas that are ecologically important, right?”

Unfortunately for fireflies, we enjoy their favorite habitats as much as they do, and we tend not to share well. Few sections of Texas have seen as much explosive growth as the town of Pfeiffer’s birth and childhood as well as the one he now calls home—two towns with natural habitats beloved of both fireflies and humans. As he points out, Comal County is the second-fastest-growing county in the United States; New Braunfels was a town of 28,000 in the 1990 Census, and today, it’s estimated at 80,000.

“I’ve come to the conclusion that basically one day this whole county is going to be one big suburb at some point,” says Pfeiffer, who with good reason comes across as a prematurely-grouchy millennial. That is one reason he feels compelled to chronicle the here and now. “A lot of the places that I’m studying right now will not exist in their current form in twenty years. They certainly won’t have the diversity they have now because people are wiping out their habitats.”

Which is not to say they aren’t doing really well far from the twin boomtowns of German Texas. “Largely the public is ignorant of the quality of fireflies we have here in Texas, and that’s been the case for a really long time,” Pfeiffer says. “People tend to think there is only one. When I tell them there are 45 species, and I get to see the most magnificent bioluminescent displays, ones that rival anything on the East Coast, they are kind of blown away.”

Pfeiffer’s obsession with fireflies came about via an occurrence almost as ephemeral as a lightning bug’s flicker. While today he hosts night hikes, gives talks, runs the website, and serves as an all-around lightning bug pundit, he couldn’t have envisioned any of that when he entered Texas State University as a freshman biology major in 2000. While in college he started an Internet company that he sold for a tidy profit and carried on in tech, consulting, and start-ups, with fireflies only a pleasant childhood memory when they crossed his mind at all. That all changed when one night about ten years ago, while diving back home from Thanksgiving dinner with his family, he heard what he remembers as a “blip” on NPR about firefly decline.

“And I had happened to buy that domain name about three months before that, so I thought there was just a connection, so I thought ‘Why not just do a website on it?’ And sure enough I did it. One thing led to another and the next thing I knew I was studying specimens in universities, getting trained at A&M and so on.”

Funny what a little blip can do.

Pfeiffer is none too eager to share his favored viewing spots—he comes across as guarding them as jealously as a dedicated angler does his honey hole. “Here you have to go where the habitat is still relatively pristine,” is all he will say. “That’s where you see the amazing stuff, and most of it is on private property.” (Dang if he doesn’t sound like a hipster name-dropping really cool bands “you’ve probably never heard of.”)

That lack of access might be a good thing. Pfeiffer points out the case of the synchronous firefly (Photinus carolinus) of the Great Smoky Mountains National Park as an example of what can happen when lightning bug mania runs amok. “That poor park is under a crush of tourist humanity, because so many people want to see those synchronous fireflies, and there’s a limited amount of space,” he says. “It’s at this fever pitch where there’s now a lottery system, and people are getting pissed off when it takes them years to get a ticket.” (Of the carnival-like atmosphere at the park, one biologist once remarked: “”The bulk of people are respectful … But the total number of people is obscene.”)

Although he won’t reveal some of his prime spots, Pfeiffer advises us to get off our couches and go outside. This is the ideal time of year to find fireflies. “We’ve gotten too lazy to really look,” he says, laughing. “Nowadays, people think looking out the window is the same as going outside, at least in the evenings. People used to go outside at night more … I’ve even seen park rangers who don’t. They have no idea what goes on in their parks at night, just because they spend all their times studying butterflies or whatever during the day. So …p eople’s habits have changed, I guess. We are still afraid of the dark. It feels like a regression in some ways.”

For the firefly, its aerial light show is the culmination of a life cycle. By the time you see them twinkling in the twilight, they’ve already spent two to four years cycling through earthbound phases as eggs, larvae, pupae, and finally, adults. Larval fireflies feast on snails and slugs and other backyard nemeses and so are beloved by gardeners—but by the time they take wing, they are singularly focused on one thing and one thing only: sex and then laying eggs, and finally, death.

Many species forgo eating during this last very horny phase of their life; a notable exception is the female of the Photuris genera of fireflies. The so-called “femme fatale firefly” mimics the amorous flash pattern of the females of the rival Photinus genus in order to seduce them into making a move, whereupon they are attacked and devoured by the Photuris female. She needs not nourishment but their essence—a chemical toxin that renders her own flesh unsavory to predators such as birds and spiders.

For their part, some Photinus phellas have learned to swipe left on many potential partners before settling on one that won’t kill them and dissolve them in acidic enzymes before they can pass on their DNA. In one lab experiment, it was found that Photinusmales sought mates for seven long days while their female counterparts, free of mortal consequences to their romantic decisions, got busy in a mere six minutes. And once they lay their eggs, they perish; like the poet said, falling far short of their star-like start, even if they give us a lifetime of memories along the way.

- John Nova Lomax for | May 20, 2019