Ephemeroptera Mass Emergence in Iowa

Mass emergence is an adaptation (presumably) to reduce predation risk… and mayflies really know how it’s done!  Males perform a courtship dance above the water (in this case above the water on a bridge!), females fly into the swarming/dancing males to copulate, and then the females release their eggs into the stream below.

 

“Whirlpool” at Lake Texoma

Lake Texoma is a very large reservoir along the Oklahoma – Texas border.  Record rains have forced the Army Corps of Engineers to open the subsurface flood gates in order to control the water level.  Opening the flood gates resulted in an interesting phenomena!

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