Summer Wildlife: Fireflies at Dusk

Summer Wildlife: Fireflies at Dusk

As the fireworks fade into the summer, another light show begins to take place in the heart of Madison Square Park. Adult Photinus pyralis beetles, also known as the common eastern firefly, begin to emerge from the cooler, more damp Park grounds and take to the sky with their flashing, aerial choreography. 

Although they seize our attention during the summer nights. P. Pyralis have been glowing since birth. Firefly eggs emit a slight glow that is visible to the naked eye––that’s if you can find them buried under the leaflitter and shrubbery in the Park. After about four weeks, they hatch into flightless larvae, where they will usually spend most of their lives living in the soil. The firefly larvae, also known as glow worms, are vicious predators. At night, they hunt slugs, snails, worms, and other insects, injecting its prey with digestive enzymes to immobilize it and liquefy its remains. After one to two years in the larval stage, the developing firefly moves into small pockets in the moist soil and pupates. While pupating, it undergoes metamorphosis, emerging from the pupa as an adult.

Summer Wildlife: Fireflies at Dusk

During the early summer days, adult fireflies will find refuge in the plant beds and bushes. Around dusk, they begin to prepare for their main objective as adults. P. pyralis use their bioluminescent abdomens to attract mates during summer nights. Typically, the male flies low to the ground, flashing a mating signal. A female resting on vegetation will then respond to the male. By repeating this exchange, the male is able to home in on her, after which, they will mate. It is widely believed that P. pyralis fireflies refuse to feed as adults—they simply mate, produce offspring, and die.

If you are in the Park after sundown, keep an eye out for a hovering light show by Elm, Sol Lewitt, and Magnolia lawns. We ask that you avoid injuring our glowing friends, and if you happen to capture any of these creatures on camera, upload your images to the online data collection platform iNaturalist to help us track biodiversity. To learn more about the insects and other flora and fauna throughout Madison Square Park, visit iNaturalist and eBird, or read more about our ongoing initiative to support our local wildlife.