by Nicole Rivard
Some people may have lamented the cancellation of fireworks displays this year, but Covid-19 has not stopped fireflies from putting on their own light shows that are just as enchanting. Plus they don’t endanger wildlife or scare pets.
Last summer I attended Audubon Greenwich’s firefly night and it was so magical strolling around the property looking at fireflies that I decided to tune into the virtual Zoom version on July 10.
It did not disappoint in terms of enlightening viewers (pun intended) about these beetles, the threats they face and how we can help them thrive. And because it was available online it reached nearly 250 people from Greenwich to Bangladesh.
What struck me the most this year is how we mostly associate fireflies with what we see this time of year—the adults using their blinking pattern like a secret code to “talk” with other fireflies and to find mates. But we are actually catching them at one very brief stage at the end of their life.
Their larval stage is equally as fascinating too and what makes them so beneficial—they are nature’s natural pest control.
Gardens are meccas for food firefly larva eat. So if you have fought off snails, slugs, mites, other various insects or worms, fireflies can lend a hand. They can help control such creatures that often prompt people who want the perfect garden to use a variety of pesticides.
Fireflies, who are also prey for spiders and other insects, spend up to 95% of their lives in larval stages. They live in soil/mud/leaf litter and spend from 1-2 years growing until finally pupating to become adults. This entire time they eat anything they can find.
Unfortunately, we also learned that fireflies are disappearing all over the world, and scientists believe it’s because of human encroachment on habitat, increased light pollution from development and traffic and pesticides.
The good news is we really can help fireflies make a comeback. Just follow these steps provided by firefly.org.
Don’t use pesticides.
Two known studies indirectly suggest that these chemicals may be harmful to fireflies and larvae. The first study suggests that lawn chemicals are toxic to insects in the lawn where firefly larvae are found. The other study provides proof that lawn chemicals are very toxic to the food that sustains firefly larvae. Both show that lawn chemicals can have a serious detrimental effect on fireflies throughout all growth stages. In addition, many communities spray for mosquitoes at night just when fireflies are active, flashing and mating.
Let logs and litter accumulate.
Some species of firefly larvae grow up in rotten logs and the litter that accumulates beneath the forest canopy. To encourage their growth, plant some trees on your property. If you have trees in your yard, consider leaving some natural leaf litter around them to give firefly larvae a damp place to grow.
Don’t over-mow your lawn.
Fireflies mainly stay on the ground during the day, and frequent mowing may disturb local firefly populations. While you may feel that you need to keep your lawn mowed for aesthetic purposes, consider incorporating some areas of long grasses into your landscaping. Fireflies prefer to live in long grasses, and doing this may boost their population in your yard.
Plant native trees.
Fast growing pine and native trees provide a good habitat for many species of fireflies. Naturalist Terry Lynch, who has studied fireflies for many years, recommends pine trees because they provide shade and the low light area provided by a canopy actually increasing the amount of time fireflies have to find a mate. Also, the litter produced by pine trees, if left to accumulate, provides a good habitat for earthworms and other small animals which firefly larvae feed upon.
Turn off outside lights at night.
Fireflies use their flashing lights to signal each other, attract mates and warn of danger. While the science is still preliminary, it’s likely that human light pollution can disrupt their flashes—making it harder for fireflies to find mates and breed. This leads to fewer fireflies mating and smaller numbers in subsequent generations. You can make your yard a haven for fireflies by turning off exterior and garden lights, and drawing your blinds at night so that interior light doesn’t brighten your yard too much.
I’m happy to say that after the virtual event was over, I sat on my porch and looked out for fireflies. They were there, twinkling in the darkness.
I appreciate them more than ever, not only for what they do for the environment but because during a pandemic their emergence each night provides much needed flickers of hope.
Nicole Rivard is editor of Friends of Animal’s quarterly magazine Action Line. She brings 24 years of journalism experience to the front lines, protesting and documenting atrocities against animals.