17 Year Cicadas

Cicadas are a common insect, and I associate their song with the end of summer, the days growing a little shorter, and school soon to start. The Periodic Cicada, however, is a rare bug indeed, at least in the sense it only comes around every 17 years, there have only been 6 emergences in the last 102 years.  But when the come they are anything but rare - they're everywhere across the Eastern US!

Many people think they are a locust, but they are not true locusts, which are actually a type of grasshopper. In the spring of their 17th year, a few weeks before they emerge, the nymphs construct tunnels toward the surface of the ground. These are visible as approximately 1/2" diameter holes in the ground.  They emerge a few weeks later, seemingly overnight, when the ground reaches a warm enough temperature, usually in June. Shortly after emergence, the males begin their chorus to attract females. This chorus is thought to be one of the loudest sounds in nature due to their sheer numbers, which in some areas can reach 1.5 million per acre. After mating, the female can lay up to 600 eggs in nests she carves in tree branches. After 6 to 10 weeks, the eggs hatch, the nymphs drop from the trees, burrow into the ground, and begin their 17 year cycle all over again.