Rare 17-year cicada to swarm post in the coming month
May 10, 2013
Potentially, within the next month, thousands of insects may emerge from Fort Belvoir's soil after spending 17 years underground.
The insects are called cicadas, which are flying bugs about the size of a quarter. The cicadas are born in tree branches and then bury themselves into soil and eat plant roots for a fixed number of years, depending on the species. The bugs emerge from the ground for mating purposes in quantities that can reach the millions. Males fly around and buzz daily in search of a female mate. The sound of the buzzing and sight of the masses of insects in any one location can be alarming, but the bugs are harmless to humans and all the adults die within a month of emerging. Cicadas should start appearing in May and June, according to John Pilcicki, Directorate of Public Works Natural Resources specialist.
"Their sole purpose is to mate. They make noise, reproduce and have a good time for about a month before they die," Pilcicki said. "Their offspring will burrow in the ground and in 17 years they'll pop up again and the process restarts."
There are various species of cicadas and the length of time each species stays underground varies. Some cicadas stay underground for 13 years, others 17 years and some even emerge every year. There is no evidence to explain why the cicadas demonstrate this habit. One idea is that the insect is attempting to avoid predators.
Whatever the case may be, the life cycle for all cicadas is short once they emerge. This year insects are expected to emerge by the billions on the East Coast, across an area stretching from North Carolina to Connecticut. These bugs, known as Brood II, spend 17 years feeding on plant roots underground. Once the insects emerge from of the ground, they shed their outer skins, crawl up trees or buildings, and fly around to find their mates. The females lay their eggs, and then the adults die in droves. All this happens in the course of four to six weeks. After another few weeks, a new generation of cicadas hatch from the eggs, drop to the ground, burrow into the soil and begin the next 17-year cycle.
Brood II is just one of several broods of 13-year and 17-year periodical cicadas: The last big bug outbreak featured Brood XIX, which created a huge buzz in Southern states in 2011.
Pilcicki doesn't know how many cicadas will emerge from the garrison's soil this month. The installation's development during the last 17 years could play a big factor in the cicada population. Several areas on post were forested when the 17 year cicada burrowed underground but these areas are now developed with buildings and asphalt. These barriers will prevent cicadas from emerging. For the cicadas that do emerge, Pilcicki said the biggest problem for community members will be nuisance. The bugs' noise could reach 100 decibels and their tough skin may hurt motorcyclists not wearing protecting clothing.
"It has the potential to be an inconvenience, depending on the population we get here on Belvoir," Pilcicki said. "They'll stay outside and they'll do what they've done for thousands of years and in a month or so they'll be gone."
Tree damage is a potential cause for concern for DPW as the tree slits the bugs create to lay eggs can lead to permanent damage. Brice Bartley, DPW natural resources specialist, doesn't expect mature trees will be affected by the egg laying of cicadas but young landscaping trees may be in jeopardy.
"The way the cicadas lay their eggs can prove dangerous to young trees because they're not as developed as mature trees," Bartley said.
DPW may prune trees after the cicadas mating period to mitigate some of the damage, according to Bartley. Homeowners may want to consider purchasing nets to restrict cicadas' access to their trees.
Cicadas are an excellent food source for fish, birds, insects and humans, Pilcicki said. People enjoy making numerous treats whenever cicadas pop-up such as chocolate covered ccadas and cicadas on kabobs. Despite the number of potential predators, the cicadas' population on Belvoir may be too great to be significantly decreased (for their next appearance), Pilcicki said.