In their field experiments, Owens and Lewis found artificial lighting had little impact on the big dipper’s mating.

The big dipper firefly, named for the swooping arc it draws in the sky, evolved to come out at dusk and does not seem to mind modern streetlights. Some are actually thriving in our well-lit world. “It gets rid of places where they can be.”įly 3 (Illustration by Hailey Haymond/The Washington Post) ‘Turn off the light’ greeni, preferred LEDs meant to imitate females that were bathed in darkness.īrightening the night not only makes it harder for fireflies to see each other, it may also trick them into thinking it is daytime, Owens said. Out in the wild, the pair found males of a related species, P. In a study published last year, Owens and Lewis found exposing a semi-nocturnal firefly species called Photinus obscurellus to a bright light on the porch completely prevented it from mating.

And I just kept the window open the whole summer.” “Our landlord didn’t insulate it, which was perfect,' said Owens, at the time a Ph.D. To test the impact of light pollution, Owens set up a mating arena on her porch in her home outside Boston in 2020 during the height of the coronavirus pandemic. The artificial light we pour into the night is interrupting these bioluminescent courtships. Increasingly, we’re the ones making it harder. (Travis Dove for The Washington Post Magazine) A firefly display at Grandfather Mountain State Park in Linville, N.C.

Lightning bugs endangered