Environment
8:39 am
Tue August 20, 2013

What Happened to All Those Cicadas?

Remember back in April, when everyone was awaiting the arrival of the 17-year-cicadas?  What happened? 

A cicada: rarely seen insect, or lunch?
Credit photos_martha

They were supposed to descend on the Triad by the millions... with their big red eyes and their buzz saw noises.  The experts said as soon as the temperature hit 64 degrees, the members of Cicada Brood II would make their presence known.  Some folks did get a visitation of cicadas, but others didn't see or hear a single bug and say they didn't live up to the hype.  Entomology professor Clyde Sorenson of North Carolina State University in Raleigh says that the lack of cicadas wasn't just our imagination.

"This was kind of an odd year for the periodic cicadas, in that because we had such a cool spring, they were really delayed in emergence," Dr. Sorenson explained.  "But compared to two years ago, when the Brood 19, 13-year cicadas came out, they were probably a good two, two-and-a-half weeks late. And that kind of made things difficult to assess."  

But that, apparently, is not all.  There's a geographic aspect to it as well  Dr. Sorenson said, "The other thing is that this particular brood that came out this year, Brood II of the 17-year cicadas, North Carolina actually represents the southern-most extreme of that particular brood in terms of geographic.  There were good emergences in places along the upper tier of counties, and as far south as Greensboro, but they didn't extend really far south into the state.  And that brood never really has; it's always been pretty much restricted to the area north of I-40. So there were good emergences in Greensboro -- in parts of Greensboro -- there were good emergences around, in the vicinity of Winston-Salem, although I didn't hear of any in Winston-Salem, and good numbers in places around Roxboro and Reidsville."  

That being said, though, Dr. Sorenson explained that even where there were good emergences, the geographic extent of pockets of Brood II cicadas was fairly small.  "Where they were, they came out in really good numbers. They came out late, but they came out in good numbers," Dr. Sorenson said.

I asked Dr. Sorenson whether, when conditions are not right, the cicadas just decide they're not coming out and wait another 17 years.  "They won't wait 17 years," he responded, as I got the feeling it wasn't the smartest question he had ever been asked. "There are what we call 'stragglers' associated with the brood.  They come out either a year, or sometimes even three years out of sync with the rest of the brood.  And it may be that, because we had such a cool spring, we're going to have a lot of stragglers next year. But they won't wait 17 years.  They can't do that, as far as we know."

I had heard that some people think that cicadas are actually pretty good eating, so I couldn't resist asking Dr. Sorenson if he'd ever eaten one.  "I have eaten one cicada just because I'm an entomology professor that teaches undergrads, and I had to be able to report the experience," he said, "and it was . . . uh . . . okay." Not exactly a rousing endorsement.  But he did tout insect-eating in general.  "There's nothing at all wrong in the world with insect protein.  Insects are fine food.  As long as they're the right insects."  Every semester, though, as part of a program for his students, he does cook some insects.  "In that case we use meal worms and crickets because they're just a whole lot more reliable to source."

And at that point, it became clear that we had pretty well exhausted the topic of why there weren't as many cicadas as we thought there would be.  

Hear Steve's entire conversation with Dr. Clyde Sorenson, Entomology Professor at North Carolina State University in Raleigh