Cicada
Every
season has its chorus—the thunder of a spring storm, the quiet
chirp of songbirds on a still winter day,
the rustling of autumn leaves in a breeze, and of course the
drone of cicadas during the dog days of summer.
Oklahoma is home to at least 12 species of cicadas. Each year
they emerge from their underground hideouts, shed their skins,
fly to the treetops, mate and then die. Different species have
different life cycles. Most cicadas live underground for two to
eight years, but Oklahoma is also home to a cicada that
biologists call Brood IV, a species that has an impressive
17-year life cycle. Many researchers believe this gap between
emergences keeps predators from growing accustomed to the
plentiful food source that cicadas offer. North America is home
to approximately 100 species of the 1,500 known in the world.
With the exception of varying life cycles, cicada species share
many of the same characteristics, including habitat, feeding
habits and breeding. The deafening call of the cicada is made
only by the male and is used to attract females. The sound is
created by rapid beating of wings against the cicada’s abdomen.
Along the abdomen are organs called tympana, which act as drums
and magnify the sound considerably. In fact, cicadas’
vocalizations have been recorded as loud as 108 decibels (dB).
After mating, the female cuts a slit in a small, tender branch
in which she deposits anywhere from five to thirty eggs. A
female may do this as many as twelve times on a single branch.
The eggs will hatch in six to eight weeks, and the nymph cicadas
will make their way to the opening in the branch. From there,
they make their way to the ground and quickly seek out an
opening in which to start their underground lives. Most cicadas
will dig between two and 20 inches deep in their search for the
grass and tree roots that will make up their diet for years to
come.
The cicada uses a beaklike appendage to literally suck the
nutrients it needs directly from a plant’s root system. The
underground life of the cicada is not well-documented. Most
researchers believe that the cicada goes through five cycles
underground, each one marked by the molting of an out-grown
skin.
The mature nymphs will emerge during warm summer nights and
seek out something solid to hold on to while they molt their
last skin. This can be anything from a brick wall to a tree
trunk. As it emerges from the hardened skin, the cicada is pale
and soft. Its wings will take several hours to harden along with
the rest of its body. By the time the cicada is ready to take to
the air, its body will have the familiar green and black
coloring. Look out for the cicada this summer when its music
begins to play, and take a guess at how many years it spent
underground waiting to play its song in Oklahoma.