Seventeen-year Cicadas: Watching a Nymph Transform

Seventeen-year Periodic Cicadas have been emerging slowly and silently in my east Tennessee yard for the past week.  No drumming music to attract mates.  No sound at all.  (See more about this in my previous post:  Seventeen-year Cicadas Emerging in Tennessee.) But, for the past two days they have been more active, disappearing up into the trees.   And today it is sunny and 69 F degrees.  A moment ago, a cicada flew by me clicking.

This slow period has offered unexpected opportunity for me to see several nymph transformations.  The adult insect emerges from its nymph shell in a soft white stage, before the exoskelton and wings have had time to harden and become the mature insect we normally see.  If I had not seen Sir David Attenbourough's excellent video, Amazing Cicada Life Cycle, I would not have known I was looking at the same insect.  

I encountered this change as it was progressing and photographed it intermittently for 79 minutes.  These transformations are happening constantly as the cicada nymphs crawl out of the ground.  It is the most magical part of the whole metamorphosis and most of the time we don't even notice cicadas until they begin their deafening song.  That is, unless they are all over your garden.

Even when they are all over your garden, as they are mine, there is nothing to feel concern about.  They aren't feeding.  They fed like crazy on tree root sap under the ground for seventeen years.  Now all they care about is mating and starting their seventeen year cycle all over again.

Notice the wings starting to increase.  They expand rapidly as the cicada emerges from the nymph excoskeleton which then becomes an empty casing.

For a period of time they hang from their casing, drying and hardening the wings and exoskeleton.  Then their wings fold over their back, still with a silvery look, until the process of hardening changes the cicada into the black, red-eyed insect we normally see.

As the weather warms both the ground and the air, the quiet will fade and the air will fill with thousands of flying and singing cicadas.  For two weeks they will mate, lay eggs, feed wildlife and fertilize the ground.  Their larvae will hatch, fall to the ground, burrow under trees in search of root sap, and start the life-cycle all over again.  

This is the second in a two-part series on the seventeen-year cicadas in east Tennessee.  To see the first post visit:  Seventeen-year Cicadas Emerging in Tennessee