Mayflies have swarmed North Carolina towns along the South Fork River this summer.
Channel 9 news partner Gaston Gazette reported they have obscured streets lights and overrun pedestrian bridges.
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The flies hatch, swarm and dies – all within their 24-hour lifespans.
Two towns, Cramerton and McAdenville, have issues with the swarms of mayflies, the Gazette reports.
Derek Merrill, a firefighter with the Cramerton Fire Department, told the Gazette that he sees mayflies throughout June and July. They hatch when it gets hot or after a good rain.