When fireflies await a night that never comes
Avalon Owens' research on how artificial light impacts fireflies was featured in a New York Times article by Veronique Greenwood on August 11, 2022. Below is an excerpt from the story; read it in full here.
A study found that while some fireflies shrugged off light pollution, members of other species failed to mate even when males and females could find each other.
As dusk deepens the shadow at the forest’s edge, a tiny beacon lights up the gloom. Soon, the twilight is full of drifting lights, each winking a message in peculiar semaphore: “Male seeks female for brief union.” This courtship plays out on summer nights the world over among beetles of the Lampyridae family, commonly known as fireflies.
The darkness in which fireflies have always pursued their liaisons, however, has been breached by the glare of artificial lights. Humans’ love affair with illumination has led to much of the Earth’s habitable surfaces suffering light pollution at night. In recent years, scientists who study fireflies have heard from people who are worried that the insects may be in decline, said Avalon Owens, an entomologist at Tufts University and 2019 Switzer Fellow.
“There’s this sense of doom. They seem to not be in places where they used to be,” she said.
So little is known about how fireflies live that it is hard to assess whether they are in danger — and if so, why, said Dr. Owens. But in a study published August 10, 2022 in the journal Royal Society Open Science, she and Sara Lewis, a professor of biology at Tufts University, shone some light on how fireflies respond to artificial illumination. Experiments in forests and fields as well as the lab showed that while some North American fireflies would mate with wild abandon, regardless of illumination, others did not complete a single successful mating under the glare of the lights.