BLUEFIELD — Across the two Virginias, an unusual phenomenon has piqued the interest of everyone from residents, to major news outlets. Swarms of dragonflies have apparently descended on the Midwest, to the Mid-Atlantic United States.
Weather radars from the National Weather Service have picked up unusual patterns that resemble rain, but without a cloud in the sky.
According to News Leader newspaper, in Staunton, Va. the dragonflies also showed up on radars in Virginia and it is common for dragonflies, especially green darner dragonflies to migrate south in the fall. However, swarms of them are unusual. Colin Studds, an animal ecologist a the University of Maryland Baltimore County told the Washington Post, “Climate warming could really disrupt the presence of this migration.”
According to the Associated Press, Entomologists say the swarms of dragonflies are quite common, and usually happen when they are migrating south to find warmer weather as winter approaches.
Bluefield Daily Telegraph Editor Samantha Perry saw a dragonfly swarm Thursday evening when she arrived home from work at her rural house in western Mercer County.
“We have acres of yard, and there were hundreds upon hundreds of dragonflies swarming above the grass,” Perry said. “It was an incredible sight. I’ve never seen anything like it. I wasn’t creeped out — in fact, I thought it was kind of magical.”
Perry said she has lived in Mercer County her entire life, and never before witnessed such an abundance of dragonflies in one place at one time.
The dragonfly swarms were unofficially reported via social media by residents from Tazewell and Mercer Counties.
Daily Telegraph Assistant Managing Editor Charles Owens noticed a large number of dragonflies swarming near the Falls Mills Dam Sunday evening.
“I thought this was a little unusual,” Owens said, noting the large size of the flying insects. “I can’t recall a past summer, and especially not in September, when so many dragonflies were visible in a single location. One of the bugs landed on a picnic table located at a shelter area at the dam. I got a good look at it. This was a large insect.”
Owens remembered reading a story earlier this year about the return of the seven-year locust, and at first, thought the dragonflies might have been locusts or cicadas. But he soon realized that these flying insects were far too large to be locusts. Plus there was no droning or humming noise that is normally associated with a locust or cicada.
In an article for The Washington Post, Matthey Cappucci, a meteorologist for Capital Weather Gang explained that there are different radar views that give Meteorologists different information. When the swarms of dragonflies were viewed through a “correlation coefficient” which differentiates shapes and sizes in the radar, it showed jagged shapes, not rain, but dragonflies?
Yet a further detailed radar view shows “differential reflectivity,” essentially, the shapes of the objects in the sky.
“Differential reflectivity reports data back as a number between negative -7.9 and +7.9,” Cappucci wrote in the Washington Post article. “If an object is as tall as it is wide, it will reflect a zero signal. But for objects wider than they are tall, that number skews positive. Within the cloud of radar returns over Ohio Tuesday evening, differential reflectivity values ranged between positive 5 and 6. That means we’re likely talking something with a decent width compared with its height. Like, say, a swarm of dragonflies.”
Cappucci reported that by Thursday of last week, dragonflies appeared to be on the radar above the Appalachian region.
Blacksburg Meteorologist in Charge, Dave Wert explained how their radar works, but said that their location has not spotted any swarms of dragonflies even though the radar is capable of seeing other animals’ migrations.
“It is one thing for them to be able to show weather but it can show temperature discontinuity, and dragonflies and birds,” Wert said. “Even though there may not be any clouds, you can see all of that. When you have migration for birds or insects, grasshoppers are notorious for this, gnats even, the radar can see those.”
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