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Dog Days Mean Cicadas Are Back — Every Year

17-year broods overshadow annual August emergence.

Last summer, the Washington area was abuzz — literally and figuratively — with the 17-year-cicadas, an oddity of nature that made suburban backyards sound like the Amazon jungle for two early summer months.

But the glamour of the 17-year brood — the species is called Magicicada — has all but stomped out the knowledge that cicadas come to Washington every year. Step outside this week and the same sound (at a lower volume) is there, a pulsating drone from the treetops, coming from a brood of Magicicada’s cousins — the Tibicen species, also called the Dog Day Cicadas, for the time of year they make their appearance.

In May and June of last year, local papers published some dozens of stories on the invasion of the Magicicadas, but many Washingtonians are so used to the sound of the Dog Day Cicadas that they mistake them for crickets, frogs and other late-summer chirpers.

Three separate Magicicada species — Magicicada septendecim, Magicicada cassini, and Magicicada septendecula — plus the Dog Days emerged last year, and the insects synchronize their calls in what scientists call “chorusing,” creating an almost deafening sound. The single species out this year is far quieter.

“Everyone gets all excited about [the 17-year-cicadas]—never say anything about the Dog Day cicadas,” said Leslie Sturges, a naturalist at Locust Grove Nature Center.

The Dog Day Cicadas are sometimes called annual cicadas, but it’s a partial misnomer. They have a 2-5 year lifecycle, but the broods overlap so that some cicadas emerge every year in July, August, and early September.

Cicadas, including the Dog Days and roughly a dozen broods of Magicicadas, which emerge in different years in different places, range throughout the eastern United States, the South and Southwest (where they occupy grasses rather than treetops), and parts of Canada, but not the plains, Rockies or Pacific states.

All of the species live underground for most of their life cycles in what Sturges called a “slow-motion lifestyle,” feeding on root hairs and sap before emerging to mate. The chorus comes from the males, who sing to attract females and die after mating.

Dog Days are green and black with black eyes, easily distinguished from the narrower Magicicadas, which have bright red eyes.

A few Magicicadas can still be found in 2005, members of their brood that missed the environmental triggers to emerge last year. They got the memo wrong, so to speak.

“They just missed. For whatever reason they were on the wrong schedule,” said Sturges, who has heard several reports of people finding the red-eyed Magicicadas this year. “They’re not going to breed, because they’re not going to find a mate. They just kind of missed the party.”

All of the cicadas are harmless to humans: they don’t sting or bite and for some are even considered a delicacy. But the 17-year invasion has the potential to wreak havoc on plants and trees. Not so with the Dog Days.

“They do feed on plant sap, but not enough to do any damage,” Sturges said, noting that the biggest danger was being bumped in the head by the clumsy fliers. “They’re not hurting anything. … They’re nice guys.”