At first, they are barely visible specks, darting, hovering, zipping past. But watch them with a guide who knows their patterns and behavior, and the colorful world of dragonflies and damselflies reveals itself.

Known collectively as Odonata, the insects scoop up mosquitoes and other prey with a basket that they form with their spiny legs.

Chris Hobson, field zoologist, Virginia Natural Heritage Program

Expert at identifying Odonata on the wing: Chris Hobson, left, a field zoologist with the Virginia Natural Heritage Program. He recently canoed through Dyke Marsh, south of Alexandria along the Potomac River, logging several new species for the wetland's roster. Virginia is home to 195 species of Odonata, but only about a sixth of those have been observed in Dyke Marsh. "Not many of them have adapted to the tide and pollution," Hobson says.

He spots a dragonfly that has adapted, an orange-and-black halloween pennant, which perches on the tips of marsh plants, "up in the air, just like a pennant," Hobson says. "I knew it would be here; just haven't seen it yet."

Hobson also points out a familiar bluet, a small cyan-and-black damselfly, the first he's seen in the marsh.

In 2011, Hobson conducted a similar survey at the tidal wetland for the Friends of Dyke Marsh. The new sightings, he says, "justify why it's necessary to conduct an inventory of species over multiple seasons and multiple years. Things change from year to year, and day to day out there."

Halloween Pennant, Celithemis eponina and Familiar Bluet, Enallagma civile. illustration by Patterson Clark

When perched, dragonflies hold their wings out, perpendicular to their bodies. But damselflies, the small, skinny cousins of dragonflies, fold their wings together, neatly streamlined down the length of their bodies.

Familiar bluet
Enallagma civile

Halloween pennant
Celithemis eponina