By Sarah Richardson
In West Virginia it’s not uncommon to spot a dragonfly (or two, or 20) as you’re kayaking or swimming on the river, but it’s pretty rare to spot them at higher elevations or away from water sources. The past few weeks, however, have brought large numbers of the insects to Greenbrier County and surrounding areas. It is common for dragonflies to migrate south in the fall as cooler temperatures settle in, and up north again in the springtime, but it is unusual of them to swarm.
Earlier this week the National Weather Service picked up “clouds” on their radar throughout the Mid-Atlantic region. These “clouds” were actually large numbers of dragonflies descending on Ohio, Kentucky, West Virginia, Pennsylvania, Maryland, and Virginia. Residents in Lewisburg, White Sulphur, Alderson, Ronceverte, Frankford, Renick, the Droop Mountain region, Caldwell, Alta, and more have reported seeing increased numbers of dragonflies, with more rural areas being prone to dense swarming activity.
A 2018 article by the Washington Post states that the migration of dragonflies, specifically the green darner, are usually almost unnoticeable since they rarely travel in a group. An excerpt from the article says, “Dragonflies are sensitive to temperature. Data from citizen scientists, who recorded the first adults of the season, suggest that green darners do not leave the safety of their ponds until temperatures reach 48 degrees. Perhaps there’s another temperature signal for the animals to migrate.”
The Post goes on to quote Colin Studds, an animal ecologist at the University of Maryland Baltimore County, saying, “climate warming could really disrupt the presence of this migration.”
However, there is little information overall on the patterns of the dragonflies. The Migratory Dragonfly Partnership, a group designed to gather and disseminate information about dragonfly and damselfly distribution and abundance North America, says that, “Although it spans three countries and has been documented since the 1880s, North American dragonfly migration is still poorly understood, and much remains to be learned about migratory cues, flight pathways, and the southern limits of overwintering grounds.”
So for now, it looks like we will have to get comfortable with our harmless, winged visitors until they continue their journey south.