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By Lyn Chimera

Many of us will remember the magic of seeing fireflies on warm summer evenings. It was like seeing fairy lights. I have been seeing them this summer in my gardens and am thrilled. Had a few last summer and there are quite a few this year. Brings me right back to my childhood.

What are fireflies and where have they gone? A recent article by the Xerces Society, a society for invertebrate conservation, in honor of World Firefly Day was extremely interesting and led me to do additional research on this fascinating insect.

Fireflies, often called lightningbugs, are not flies at all but a type of beetle of the family Lampyridae. There are over 2,000 species of fireflies and surprisingly only some species can glow (bioluminescence). It’s a chemical reaction within the firefly that causes the light. Unlike most light which generates heat the light from a firefly is cool. In some species the males flash their light to attract a female. In other species both males and females can glow. Even the firefly larva may glow depending on the species. Firefly larva are carnivorous and eat small creatures like snails and slugs which can be helpful to gardeners. Adults live off nectar and pollen or eat nothing at all as they only live a few weeks. Predators such as birds and toads stay away from fireflies as they have toxic foul tasting blood. Their flashing light is a warning signal to stay away. Fireflies are nocturnal. During the day, they spend most of their time on the ground. At night they crawl to the tops of blades of grass and fly into tree branches to signal for mates.

There are more than 20 species of firefly in NYS but the ones in our area Photinus pyralis, the common eastern firefly, is the most common. The males fly in species-specific flight patterns, flashing an amorous code to females, who wait on the ground.

So why are there so few fireflies? There are a variety of factors at work. One is loss of habitat. Firefly larvae need forest litter and the rotting wood of decaying logs near standing water, sites that are harder to find today. Adult fireflies need trees, tall grass and leaf litter. Light pollution is another major problem. At night there are so many lights from streetlights to houselights and garden illumination that it disrupts their natural behavior cycles and interferes with their ability to communicate and find mates. Some areas are so well lit it is like daylight 24/7 and the fireflies don’t know it’s night.

What can we do to help these interesting beetles survive? Quite a lot! Check out how much light you generate outside your home. Is there outdoor lighting that can be turned off with a timer, blinds or curtains could be closed, and shield your porch lights to focus the lights downward instead of out. A big factor is pesticide use. Don’t use pesticides or lawn sprays. Remember pesticides kill the good guys with the bad. Not only does it kill the fireflies but the other insects they eat. Over-mowing your lawn may disturb your firefly population. Mow at least 3 inches or higher.

Create an environment that welcomes fireflies by leaving leaf litter in garden beds as mulch or have areas of leaf litter in places around the garden. Also let logs or large branches accumulate. Always a good habitat for insects. Dedicate an area of your land/yard to remain in a natural state. Keep these areas moist which increases the survival of the larva.

Try a lightningbug habitat in part of your yard and enjoy the thrill of seeing them and knowing you are helping a beneficial insect that is in decline.

Lyn Chimera
Lessons From Nature