Lights Out

After they mate, the female lays her eggs in the ground, which take a few weeks to hatch. (Their mother is dead, like in Charlotte's Web.) The carnivorous incandescent larvae (a.k.a. glowworms) slither around eating slugs and snails. They spend the summer bulking up, then they tunnel into igloolike holes in which to winter; in the spring they start eating again, and the next year -- two years later -- they emerge as fireflies.

Then they dive into midnight mating orgies. Then they die.

---

There's a myriad of reasons why fireflies are vanishing. One is the fact that in most cities it doesn't really get dark anymore. In Little House on the Prairie days, there were plenty of fireflies, because after sunset people blew out their candles and it was dark. McDonald's glaring golden arches didn't light up the night, and there weren't streetlights flooding parks and roads making night dim, instead of dark.

If it isn't dark, fireflies can't find each other. If they cannot see each other, they cannot mate, and then there can't be more fireflies.

Other reasons why fireflies are vanishing from cities include pollution and mosquito spray programs. Plus fireflies like to be near water -- they like creeks and streams. We have bayous, but paving over and draining them destroys firefly habitat. And as more wells are built, water levels are lowered and we lose surface water, which eliminates the habitat.

Even out in the suburbs (where you notice if you're driving without your headlights on), when houses and barns are built, the soil is shaken up and shoved around, killing earthworms, slugs and snails that firefly larvae feed on. People who care about their lawns are less likely to have fireflies than people who let their grass grow and don't disturb the dirt.

It might not be entirely our fault that the fireflies are disappearing. It could be the fire ants that have been making their way up from Mobile, Alabama, since the late 1800s. (Of course, we're the ones who let the fire ants on that South America ship...) Fire ants eat firefly larvae, which means no fireflies. That's the theory supported by most entomologists, says Sara Hicks, a biology master's student at the University of Houston. Fire ants don't like cold weather, so they don't venture north of Houston -- hence there are lightning bugs in Dallas and New York.

Aside from fire ants, there are other firefly hunters: kids who are trying to trap money, not magic, in a mayonnaise jar. These are members of the "Firefly Scientists Club," operated by the St. Louis-based Sigma Chemical Company, which provides Coke-can-size shipping cartons and pays a penny apiece for lightning bugs.

Millions and billions of blinking bugs are caught for the glowing part of their tails. The cold light comes from two chemicals: luciferin and luciferase, which are used to detect ATP (adenosine triphosphate). ATP is in every living cell, which is why once upon a time researchers thought they could send extra-fat lightning bugs into outer space to find aliens. More practically, researchers know that cancerous cells contain lower-than-normal levels of ATP, and blood extracted from heart attack victims contain higher levels of ATP. With the luciferin-luciferase, researchers can also detect bacteria in milk, water and meat. It's so sensitive they can find one drop of contaminated water in an Olympic-size swimming pool.

"You can be proud that Sigma has supplied these important chemicals to researchers throughout the world for over 30 years," touts a promotional why-do-we-do-this pamphlet provided by Sigma.

Proud isn't the word people like Lloyd use to describe their feelings on scientists lobbing off lightning-bug lanterns and mashing their tails into a paste. Especially since it's an unnecessary action, because luciferin and luciferase have been cloned.

Sigma officials told The Wall Street Journal in 1993 that their clients like organic, natural products instead of the man-made generic substitute. That's changing, though.

"We're trying to switch people over," says Bob Gates, a chemist at Sigma. "It's a lot easier to make."

Gates has heard that firefly numbers are dwindling, but he doesn't think Sigma is to blame.

"The number of fireflies in the world compared to the number of fireflies we use is not even a measurable percentage of the fireflies in the world," he says.

He knows that his scientific colleagues report that soon there might not be any fireflies left. That doesn't bother him.

"I have no feelings on that at all," he says.

---

The thought of no more fireflies bothers Donald Burger. A lot.

Despite lack of success, he's still hunting. Burger put up a Web site on July 4, 1996, declaring his goal to bring fireflies back to Houston. He was hoping that a scientist or a breeder or someone would write in that he was a "dunderhead" and that there was a simple way to fetch fireflies. He was hoping someone would tell him where he could buy a firefly starter kit.

His Web site is "bait," he says. "I'm trying to reel in the firefly fish."

Instead, he has reeled in other firefly fans. People e-mail him their memories of catching fireflies and say that they're sad that they can't catch them with their kids. They send poems and letters, and some people in faraway places have offered to send fireflies.

He has always written back that he'd love to have a coffee can full of flies and that he'd be happy to pay the FedEx bill. No one has ever sent any.