17 years in the making, this spring's cicada invasion generates early buzz
After hanging around underground for 17 years, billions of flying bugs known as cicadas are due to sweep over the East Coast starting sometime in the next month. And although it's too early to predict exactly where or when the brood will appear, this spring's emergence should rate as the most closely watched bug-out in history.
"For entomophobes, this is the season of despair. For the entomophiles, this is the season of joy," said University of Maryland entomologist Michael Raupp, using highfalutin terms for bug-haters and bug-lovers.
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The outbreak is expected to start in the Carolinas in April or early May, and work its way up northward to Washington, Philadelphia and New York by early June. Some observers have already reported the first signs of the emergence. The timing depends on the weather: Cicadas dig "escape chimneys" up from the ground where they've been maturing for the past 17 years — and when the temperature reaches 64 degrees Fahrenheit (18 degrees Celsius), that signals the insects to rise up, wriggle out of their shells, take wing and look for mates.
The bugs are mostly harmless to plants and humans. The worst a cicada can do is poke you with its pointy proboscis. But the 90-decibel buzz of a sky-darkening swarm can be a bit unnerving to the unprepared. Raupp recalls one harrowing tale from 1962's outbreak, when "the kids were shrieking in the playgrounds as cicadas divebombed them."
In Raupp's view, however, the pluses far outweigh the minuses. The cicada nymphs help aerate garden soil with their burrowing, and when they emerge, the bugs represent a culinary bonanza for birds and other species. (They're said to taste like asparagus. Or shrimp.)
Besides, cicadas are cool. "Without a doubt, they are a true marvel of nature and one that should be enjoyed whenever possible," Raupp writes on his Bug of the Week blog.
It's thought that the 17-year life cycle arose to keep the cicadas' predators off their game, and perhaps make the most of climatic variations. Scientists even suspect that the number 17's status as a prime number plays a role. (Some periodical cicada species emerge every 13 years, and 13 is also a prime number.)
This particular group of cicadas, known as Brood II, hasn't surfaced since 1996. But other broods have had their own day in the sun during the intervening years. The big ones include Brood X ("The Big Brood"), which last came out in 2004; and the 13-year Brood XIX ("The Great Southern Brood"), which emerged in 2011.
This year's brood is notable in that it should spread out over the United States' most densely populated region. Entomologists expect the cicadas to show up in the countryside, in woodsy suburbs and even in urban locales such as New York's Central Park.
The New York-based Radiolab science show is preparing for "Swarmageddon" by helping citizen scientists build soil thermometers. Readings from the "cicada detectors" are being shared via an interactive Cicada Tracker map. Meanwhile, the Magicicada website keeps up its own database of cicada sightings. That website, supported by the National Geographic Society, also provides tons of information about the species and what to do with them. (But if it's recipes you need, you might have to
look elsewhere.)http://cosmiclog.nbcnews.com/_news/2013/04/09/17676853-17-years-in-the-making-this-springs-cicada-invasion-generates-early-buzz?lite
