A night sky is shown in the Dolly Sods area. The flashing of fireflies, or lightning bugs, is an iconic sight on summer nights, but Nellie Heitzman, a WVU master’s student in entomology, said a chance to glimpse the coordinated pulsations of a species called “synchronous fireflies” is much less common. (WVU Photo/Brian Persinger)
As rare “synchronous fireflies” — which coordinate their pulses of light in time with each other — emerge in Appalachia, a West Virginia University researcher said firefly enthusiasts should take care not to disturb the insects’ mating behavior with flashlights or headlights.
Adult fireflies live approximately two weeks, and their staggered emergence means they can be viewed from early June to July.
Nellie Heitzman, a graduate student in entomology at the WVU Davis College of Agriculture and Natural Resources, said synchronous fireflies are actively seeking mates when they emerge. The timing depends on temperatures and populations at lower elevations emerge first.
Synchronous firefly displays draw tourists each year to locations that include Great Smoky Mountains National Park and West Virginia’s Watoga State Park.
Quotes:
“The synchronous firefly species, Photinus carolinus, has a unique behavior in which the males cooperate to amplify their flash pattern, and the females respond with their own. This behavior may be due to the importance of mating with the same species because a mistake means lost time and resources as well as potential predation by other species.
“The flashes start around 10 p.m. Initially, a few males will begin the display with five to eight successive flashes, followed by approximately eight seconds of darkness. More males join, and the pattern becomes more pronounced by 11 p.m.
“Since fireflies communicate via light signals, any additional light may disrupt their pattern. However, they are less sensitive to red light, so visitors should use a headlamp with a red light setting or a white light covered with red film. Sound also causes irregularities in the pattern. Visitors should stay on designated paths, as the females are often in the vegetation signaling to the flying males.
“Synchronous fireflies prefer temperatures of at least 50 degrees Fahrenheit and do well in humidity but may have trouble flying in the rain. They have been found throughout Appalachia in dark, heavily forested areas where they tend to be less disturbed. They also may be found near a water source, as there are indications that the flashes reflecting off the water may increase their efficiency in attracting a mate.
“While the season’s generation of adult fireflies is in the mating stage, the larvae dwell in the soil for two years before emerging, so it’s very important not to disturb the soil in the areas they inhabit.” — Nellie Heitzman, graduate student, entomology, WVU Davis College of Agriculture and Natural Resources
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