Are they fireflies, glowworms or lightning bugs? It doesn’t really matter what you call them because one of our favorite sights of summer are those yellow-green orbs flashing against the backdrop of the garden at dusk.
Fireflies are not flies. Nor are lightning bugs, bugs. And no one would think that a glowworm is actually a worm. These creatures are in the genus Lampyridae and are classified as soft-bodied beetles. They commonly inhabit areas like meadows, open woods and of course, Midwestern backyards. They seem to prefer moister habitats for breeding and laying eggs, and they are carnivorous when young, eating slugs, snails and worms. As they age, the adults shift their diet to pollen and nectar.
More than 2000 species of these luminescent beings sparkle and flicker in yards and forests all over the world. Firefly lamps glow in many colors, from yellow which is common in our area, to orange, green, and even blue. The light is produced by a reaction called chemiluminescence that occurs between a chemical they produce, called luciferin, and oxygen. Some flash in quick, single flickers, while others leave long, glowing trails. Not much is known about the meaning of the lighting patterns, but researchers are trying to unravel the mystery. It is believed that fireflies may use different blinks to attract mates, to discourage predators, or to show off for rivals.
We don’t notice fireflies until they’ve reached adulthood, but they are able to produce light in all life stages. Eggs, larvae and pupae emit light! The flashing patterns produced by the adults are called lanterns, and often synchronize, especially by males during courtship.
But these tiny flashers bring more than whimsy to the backyard picnic table. Their bioluminescent abilities have led to the development of new flashlight and flare technology. The chemicals that produce the light are being investigated in research for fighting cancer, multiple sclerosis, and heart disease. That is one beneficial insect!
How can you attract and protect them? First dim your lights! Bright outdoor lighting can mask the mystery. Leave a little messy corner in your yard for them to congregate. Super tidy environments are not their favorite. They’d prefer a bit of leaf litter to lay their eggs. Small trees and open shrubs provide protection from predators. They also like a water source, just as birds and butterflies do. Fireflies are attracted to a small pond or other gentle water feature. When gardening, use natural fertilizers and avoid insecticides. Finally, let your lawn grow a little taller. Fireflies prefer long grass for mating.
Some recent studies show that firefly populations are declining, with several North American species in danger of extinction. Causes range from habitat loss, overuse of insecticides and light pollution. So add fireflies to that list of wild creatures you’d like in your yard. They’re certainly as beautiful as butterflies, as useful as honeybees, and as magical as hummingbirds.