COLUMBUS, Ohio -- Neighborhoods, parks, wooded areas and forests throughout southern Ohio will soon be filled with the cacophony of thousands of periodical cicadas, emerging from underground after 17 years of development.
Brood XIV, one of the largest broods of periodical cicadas in the northeastern United States, is anticipated to emerge any time throughout a region that includes parts of Georgia, Indiana, Massachusetts, Maryland, North Carolina, New Jersey, New York, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia and Kentucky.
"Though noisy and alarming to some in appearance, cicadas are harmless insects whose sole purpose in life in simply to mate and continue their species, although many become the next meal for a bird or other animal", said Barbara Bloetscher, an Ohio State University Extension entomologist.
"Cicadas are one of the more primitive insects whose existence can be traced back millions of years," said Bloetscher. "They may look scary, but they don't bite. In fact, they are actually kind of fun to handle."
Cicadas, often mistakenly called locusts, are true bugs, not grasshoppers. They lay eggs within the branch tips of trees, mainly those with soft wood. The young emerge 6-10 weeks later, drop to ground and burrow around tree roots where they spend their development feeding on the tree's nutrients.
"People think that cicadas kill trees, which is not the case. They can potentially damage very young trees and can be of concern to nurseries, but on more mature trees the damage is only cosmetic," said Bloetscher. "It's sort of like nature's pruning."
Soil temperatures trigger the emergence of the cicada nymph, which then molts and spends 2 to 4 weeks finding a mate. Its efforts are characterized by its "song," -- a loud repetitive sound created by blowing air through vents on its abdomen. Females seek out males with the louder, more vigorous songs.
"Females can lay large amounts of eggs, up to 400 at a time. The periodical cicadas emerge in such large numbers as a survival tactic," said Bloetscher. "They are a great protein source for birds and other animals, so the large populations are a confusion factor for animals. They simply can't keep up with all of them so the likelihood of survival is greater."
Periodical cicadas are categorized into broods depending on the year that they emerge, although occasionally they emerge a year earlier or later. In Ohio, the periodical cicada consists of 3 species, and emerges every 17 years. Southern states may experience an emergence after 13 years and contain many more species. The annual cicada is a different species that emerges annually, singing harmoniously during the "dog days of summer."
The largest populations of Brood XIV periodical cicadas are anticipated to emerge throughout southwestern Ohio by the beginning of June and last a few weeks.
The next 17-year periodical cicada species won't emerge in Ohio for another eight years. Brood V is anticipated to emerge in 2016, and Brood VIII won't emerge until 2019.
For more information on the cicada, log on to OSU Extension's Ohioline at http://ohioline.osu.edu/hyg-fact/2000/2137.html or http://bugs.osu.edu/~bugdoc/PerioCicada/index.htm.