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5/01/2016 8:58 am  #1

Wait, What’s That Noise?

Wait, What’s That Noise? Cicadas, the New Batch, to Sound Siren Song in 5 States

After a 17-year wait to mate, expect a lot of noise from the next brood of cicadas, which will start to emerge next month in parts of five states.

Western Maryland, eastern Ohio, southwestern Pennsylvania, northwestern Virginia and most of West Virginia are expected to see the ascension of the so-called Brood V.

There are six species of periodical cicada, three with a 17-year cycle and three with a 13-year cycle. Periodical cicada populations — called broods — are identified by Roman numerals.

“We think of them as the Methuselah of the insect world,” said Gregory Hoover, an ornamental entomologist at Pennsylvania State University.

This particular generation of insects last emerged in 1999 (a year filled with anxiety about a different kind of bug, the computer-based Y2K).

What are cicadas?

The periodical cicada is native to North America and exists nowhere else in the world, Mr. Hoover said. Researchers have been tracking the broods for more than 100 years. In the late 1800s, American entomologists created the first good maps of the insects’ ranges. Relying on a form of crowdsourcing, they sent circulars to postmasters in the Eastern United States each year and recorded their responses.

The insects are about one and a half inches long, with red eyes and orange veins in their wings. They are smaller than the dog-day cicadas, which are usually heard in late summer.

How do they make that buzz?

The periodical cicadas — the males in particular — will be the noisiest. Individually, a cicada’s song sounds like a tiny maraca shaken at high speed that then fades into a noise resembling an electric buzz.

In a swarm, the cicada’s high-pitch hum can reach 85 decibels, or slightly louder than a passing diesel train. Males begin their singing shortly after they emerge, while the females are mostly silent, Mr. Hoover said.

The sound comes from their tymbals, the corrugated exoskeleton on their torso that they contract and release.

The insects cover their own hearing organs to avoid doing damage. As the website Cicada Mania noted: “A cicada applied directly to the ear (do not do that) gets in the range of a loud rock concert and ambulance siren, which will cause hearing damage. Again, do not put cicadas in or around your ears, and avoid seeing Metallica live in concert.”

How does this brood compare with others?

There are many broods of periodical cicadas, with different geographic ranges and life cycles. In 2013, the arrival of Brood II was most evident in places like Staten Island and parts of the Hudson Valley.

Brood V’s population will number in the billions, but the distinction of “Big Brood” goes to Brood X, which saw cicadas in more than a dozen states in 2004, Mr. Hoover said.

In general, development in forested areas that remove trees, which are the habitat for periodical cicadas, has drastically reduced their populations, he said.

Should I be worried?

Although adult cicadas are harmless to people, they can cause some damage to shade and fruit trees, Mr. Hoover said. They can also cause a mess and discomfort for humans.

In addition to the eerie noise cicadas emit, they leave behind casings that can coat decks and patios, prompting some homeowners in the past to get power washers to remove them. If you have a phobia about insects, this will be a time of high anxiety. Dog owners have discovered the undigested remnants of the insects from the upset stomachs of their pets.

But for some other animals, such as birds and fish, the emergence of the periodical cicada means a bumper crop of food. Trout, bass and carp “will literally gorge themselves” on the adult insects, Mr. Hoover said.

How do they know when to emerge?

The lead-up to cicadas’ emergence is a prolonged, low-key process. Cicada nymphs spend 17 years underground, where they “await an undetermined signal for emergence,” Mr. Hoover said.

A combination of soil temperatures reaching 64 degrees and light rain seems to trigger their ascension, he said. The nymphs climb trees and within an hour, they shed their skins and become adults.

Ten days later, the mating begins. Each female lays up to 400 eggs in the twigs of more than 75 species of trees.

Nymphs hatch in six to eight weeks and then drop to the soil for a period longer than four presidential administrations before they re-emerge and the cycle continues.

Last edited by Goose (5/01/2016 8:59 am)

We live in a time in which decent and otherwise sensible people are surrendering too easily to the hectoring of morons or extremists. 

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