Dave Taft; Nicole Vergalla Nothing can extinguish the enchantment of fireflies. For adults like me, they occupy an unshakable niche in the pantheon of the still-magical. Who isn’t speechless at the edge of a dew-dampened meadow when evening makes a galaxy of a thousand tiny insects?
Scientifically, the firefly’s glow is fairly well understood. Simplified, fireflies produce the aptly named compound luciferin, which, oxidized by the enzyme luciferase in the insect’s last abdominal segments, produces the bright green light we love so well.
Very little of this chemical reaction’s energy is expressed as heat; the resulting bioluminescence is a “cool light†and is not unique to fireflies. But fireflies are appealing. They are about as cute as phosphorescent creatures get â€" just ask anyone who has examined one of those sunken-eyed, deepwater fish, or a glowing, slimy fungus. If nothing else, they are certainly more accessible.
The common eastern firefly, Photinus pyralis, is actually a beetle, and within the confines of New York City, may actually be more common now than a few dozen years ago. Restrictions on the use of pesticides, and greater efforts to protect natural areas citywide, can be thanked for this abundance. Anywhere there are fields or lawns, in any borough, there are probably fireflies.
Fireflies do not glow for enjoyment. Like so many other natural wonders, it is a behavior contrived to attract a mate â€" each firefly species has a flashing pattern of its own.
In the case of our common eastern fireflies, the males fly at dusk, flashing their signals. The females, though possessing wings (not all female firefly species do), often do not fly but attract mates by returning the flash in the correct sequence. The males land near the females, and if all goes well, eggs are laid in moist ground nearby. An average firefly may live from 5 to 30 days, sufficient to find a mate, but not much more.
Most firefly larvae are predators of snails and slugs, and the adult females of several species are carnivorous as well.
In fact, one of the insect world’s most compelling adaptations is the behavior of the firefly named Photuris pyralis. A female of this species mimics the flash pattern of female Photinus fireflies. An unsuspecting Photinus male is attracted to her flash like an insect Ulysses. He lands, only to be eaten by the deceptive Photuris female.
To see fireflies, follow the footsteps of your inner child. The best container for a firefly hunt remains the mayonnaise jar â€" with holes dutifully punched in the top. A butterfly net will improve your catch but is hardly necessary. If you fantasize, as my brother and I always did, that enough fireflies could create a reading lamp, my recommendation is to catch other insects. But even given the limited wattage, few things in life are as magical as a child’s face illuminated by the flashing light of a firefly in a bottle, on a rickety old table, at last light, in someone’s yard or a local park.
