Mayflies, those aquatic insects with the long bodies, twin tail filaments and delicate, lacy wings, are a very good environmental sign. The presence of mayflies indicates the water body from which they emerged is generally healthy and unpolluted. As forage for many types of fish, birds and other animals, mayflies are also an important part of the food chain.
Mayflies live for a year or two as nymphs in the muddy bottoms of freshwater lakes. Upon maturing they rise to the surface and enter the winged adult stage, which typically lasts just 24 to 72 hours and is simply a frenzy of mating and egg-laying.
But once in a while, mayflies can become too much of a good thing, as this Doppler radar video indicates. Dayton, Ohio’s WHIO TV/Radio Chief Meteorologist Eric Elwell recently posted this clip showing massive mayfly hatches in Lake Erie’s Western and Central basins.
Very thick mayfly hatches close to land have been known to cause bridge and road closures, as well as car accidents when auto tires lost traction on their slippery remains. At times heavy street-cleaning equipment has even been required to clean up the aftermath of a massive hatch.
Judging from the radar image, these hatches covered many square miles, more than likely causing city crews and property owners to put in many hours of clean-up duty.
Radar image is screenshot from Facebook video; mayfly image from Wikimedia Commons