Duluth Weather Radar Detects Huge Mayfly Hatch
'Tis the season, mayfly season has returned to the region, and the nasty bugs are showing up all over the state and were even spotted on weather radar this morning.
The National Weather Service in Duluth posted a photo of what they suspect is a giant mayfly hatch caught on their weather radar. They say due to the timing of 5:46 AM and the location, near the St. Croix River in Pine County just south of Hinckley, that is more than likely a mayfly hatch.
They can also determine that they were picking up something biological versus meteorological "by using Correlation Coefficient. CC is a measure of the consistency of the shapes and sizes of targets within the radar beam." If you look at the photo above, all the green on the map indicates a biological target like birds or insects, like the mayfly.
According to the Minnesota Department of Natural Resources, adult mayflies rarely live longer than a month and spend 99% of its life as a nymph before transforming into mating adults. Mayflies mate with the female insects, flying through a swarm of male mayflies, the females return to the water after that, lay the eggs and die.
While us humans are grossed out by the bug, it's actually a good thing and a sign of healthy waterways, back in the 1960’s, 1970’s and early 1980’s, sewage was such a problem in our waterways that the mayfly population was very small, but today with modern sewage treatment facilities and regulations on the disposal of toxic chemicals, the mayflies have returned.