Natural Highlights: Whirligig Beetles



Whirligig Beetles (Gyrinidae) are very common on the surface of all kinds of water in the Midsouth, often seen in large groups gyrating and spinning crazily around each other, somehow without ever colliding.  There may be a method to this madness, however. Apparently the tiny waves produced by moving in circles are more effective at helping the beetles detect prey items at the surface.  A whirligig beetle's club-like antennae pick up waves which bounce back, much like marine mammals and bats sound waves in echolocation.  They eat insects, dead or alive, which fall might fall into the water, and any other small aquatic creature they might encounter.

Whirligigs are handsome, shiny, metallic brown insects, designed for rapid swimming both on and below the surface of the water.  But they are also quite capable of flying and crawling on land if necessary.  They are air-breathers, so to swim underwater they take a bubble of air with them at the tip of their abdomens. They also have eyes capable of seeing above and below the water at the same time.  

Check out the following links for more information on Whirligig Beetles:

  Whirligig underwater.

Posted by Cathy Justis at 7:26 PM