- The Washington Times - Monday, May 29, 2000

BALTIMORE The 17-year cicada wasn't expected until 2004, but the bugs have been showing up across Maryland early, puzzling some scientists.
The 17-year cicadas were last seen in 1987. They've been sighted recently in suburban landscapes in northern Maryland.
"They're in my yard, in my trees they're everywhere," said Lamont Brown, who lives off Liberty Road in Baltimore County. "The birds are having a good time. The ants are having a field day. Everybody prospers."
According to life-cycle charts, the insects were not expected to see daylight until 2004. Why now?
"The first thing people say is 'global warming,'" said Gaye Williams, an entomologist with the Maryland Department of Agriculture. "It doesn't have anything to do with global warming. This is not the apocalypse."
The emerging bugs belong to a particular group known as Brood 10. The name refers to one of 12 geographically distinct classes of 17-year cicadas that appear mostly in the Northeastern United States.
Tens of thousands of untimely Brood 10 cicadas also appeared this week in a six-county area in southwestern Ohio.
"It's really cool," said Gene Kritsky, a cicada expert at the College of Mount St. Joseph in Cincinnati. "We have six to eight thousand on campus right now. I've seen some trees with hundreds in them. Yards are inundated. I've even started hearing cicada calls."
Mr. Kritsky was not surprised that the cicadas came out early, however. Every year for a decade, he has taken his students to a nearby orchard to dig up a few hundred of the brood and monitor their growth.
He discovered some time ago that a portion of the bugs had skipped the usual four-year dormancy stage and were growing at the same rate as 13-year cicadas.
Mr. Kritsky is recording samples of cicada counts from Ohio to Maryland submitted to his Web site. The information will help document what may be an unusual evolutionary strategy.
Only a small percentage of Brood 10 is emerging, Mr. Kritsky said. He guesses that an overpopulation of cicadas underground may have caused a subset to relieve competition for food by coming out early.
Cicada expert Chris Simon of the University of Connecticut was not surprised by the early appearance of Brood 10. Mr. Simon was roaming the foothills of South Carolina and Georgia this week sampling an emergence of Brood Six cicadas when she heard of the Ohio and Maryland outbreak.
"We expected it," Mr. Simon said. "We call it 'bet-hedging.' " Looking at maps of geographic boundaries of cicada broods, entomologists have noticed that major territories for 17-year cicadas often overlap, she said. In Virginia and Southern Maryland the Brood Twos overlap with Brood Sixes from the Carolinas. They emerge at four-year intervals from each other.
Biologists believe the occasional four-year acceleration prevents a brood from "putting all its eggs in one basket," Simon said, giving the bugs a chance to create a class.

LOAD COMMENTS ()

 

Click to Read More

Click to Hide