Scientist: Mayflies’ Arrival Means Mon River is Cleaner

Says the insects not attracted to orange lightbulbs

Morgantown Dominion Post
26 June 2012
By Jim Bissett

The thousands of mayflies found clinging to a showroom window in Morgantown on Sunday night only seemed like the opening act to a Bug Apocalypse, an area entomologist said.

In fact, said Jim Amrine, a retired WVU professor who still does research in his field, their appearance in town bodes pretty well for the nearby Monongahela River.

“They’re coming from the Mon,” Amrine said. “That’s where they hatch. It’s a good indicator that water quality is improving. It means these guys are able to survive.”

There was no mayfly traffic in Morgantown when he arrived at WVU in 1975, he said, noting that the river that runs along the University City wasn’t much for splashing or hatching, then.

Peter Grant, an entomologist who edits the “Mayfly Newsletter” from Southwestern Oklahoma State University, said he remembers seeing huge “emergences” of mayfly-hatches on the shores of Lake Erie, in Pennsylvania, when he was a boy in the 1950s.

“That’s what they’re called,” he said, by telephone from his office in Weatherford, Okla., “but everything stopped as the lakes and rivers got more and more polluted. The emergences have picked up in the last 10 years as the water’s gotten cleaner.”

Mayflies only live 24 hours after growing to their full measure of about an inch in length. Amrine said it was too bad the Morgantown mayflies got sidetracked by those showroom lights at Cardello Electric.

That’s because it was a fatal distraction from an already fatal job description, he said, which is to mate, lay eggs — and die.

Males die promptly after mating. Females die right after laying their eggs, which can be up a thousand at a time.

There are at least 4,000 varieties of mayflies in the world.

In the meantime, if you don’t want them around, Amrine said, just shut off your porch light or pop in an orange light bulb.

“They’re not attracted to orange,” he said. Several cities in the country have taken the illumination lead, he said, switching over sodium vapor bulbs that give off that orange-tinged, pinkish glow, opposed to fluorescents or incandescent bulbs.

It knocks back the mayflies, Amrine said, but that’s no fun for someone who studies the winged creatures. That’s why he’s switching out the bulbs on his back deck, he said, chuckling.

“The brightest I can get,” he said.