Incredible Mayfly Facts!

    This image shows a large mass picked up by the National Whether Services Doppler radar that grows out of the Mississippi River and drifts northward.  It just so happens that this is not weather that the radar is picking up, it is MAYFLIES!  When mayflies mate the swarm can grow so large that it can actually be picked up by weather stations Doppler radar. 
    The first image is from a mayfly hatch on June 30th 2006 on a Friday evening.  This is typical of mayflies to mate in the evening because this helps them predators.  The hatch continued to grow until early morning covering roads and tributaries in the La Crosse area.  Personally, I find this incredible.  The fact that a species of insect can create a swarm this massive overnight is hard to believe.  This video shows a different vantage point of mayfly hatches that will show what a swarm like this would look like in person.

    The National Weather Service Doppler radar from the Detroit/Pontiac area also caught a mayfly hatch in action.  These are progressive Doppler as the mayfly hatch continues to grow.  The mayflies (Hexagenia) each year in late June and early July hatch along the coast of Lake Saint Claire which is between Ontario, Canada and Michigan, United States.  These particular radar images are from a July 26, 2001 hatch which began around sunset.  The National Weather Service estimates that the swarm is comprised of hundreds of thousands of mayflies.  The first Doppler image is from 9:21 PM and the last Doppler image is at 10:59 PM.  That m that it only takes one hour and thirty eight minutes for the mayflies to go from a little blip on the radar by Mount Clemens to the massive swarm seen covering the majority of the lake, that seems pretty fast! These Doppler radar images, complements of the National Weather Service, show how incredibly large and fast a swarm of mating mayflies can develop.  Mayfly hatches truly are a spectacular feat, it might have you scratching your head as to what kind of food can fuel this large of a swarm.  Take a look at the nutrition section to get a feel for what these mayflies eat, how they digest their food, and how they transport nutrients.  Cant get enough interesting mayfly facts?  Visit for more!


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