According to WCCO-TV, the massive hatch blanketed the upper MIssissippi River and the surrounding area in La Crosse, Wisconsin, Sunday.

A few hours after their emergence, the roads became slimy and the visibility became so low that it caused a car accident on a bridge linking Red Wing and Hager City which left one person hospitalized with injuries.


Even though the Mayflies are a major annoyance, entomologist Petra Kranzfelder says the hatch is an indicator of good water quality and are an important food source for fish and other animals. Thank goodness they only stick around for a couple of days!