They fly but don’t bite

08/05/2010 12:00 AM |

A dragonfly perches atop Annette Oliviera’s finger. Contrary to what some believe, dragonflies don’t sting and their mouths are too tiny to bite humans.

If you don’t stop talking, they’ll sew up your lips.

That was the dragonfly myth people of a certain age might recall hearing from their elders. And because of a dragonfly’s size — some as long as two inches — and swift flight — often 30 to 35 mph — they can appear threatening to the untrained eye.

But as children and parents will discover this weekend at the North Fork Audubon Society’s annual dragonfly day at Skipper Horton Wentworth Park in Greenport, dragonflies are no threat to people. Because they dine on other insects, they are highly beneficial garden visitors.

Absent a case of entomophobia (fear of insects), a close look at a dragonfly will reveal iridescent eyes and often vibrant wing colors.

As is often true in nature, the males have the most stunning array of colors, according to dragonfly enthusiast Annette Oliviera. Like butterflies, dragonflies undergo a metamorphosis, emerging from an exoskeleton called an exuviae into their full beauty. That process takes place near freshwater ponds, Ms. Oliviera.

“They really are beneficial,” she said. “There’s no downside to dragonflies.”

The runoff ponds at the Greenport park, east of the Southold Information Center on Route 25, provide a unique breeding ground for dragonflies, Ms. Oliviera said. It was there two years ago that she discovered the first four-spotted pennant dragonfly ever seen in New York State. She has also found many dragonflies at Inlet Pond Park in Greenport.

“Here’s the thing about dragonflies — it’s one of those creatures that can really connect people with nature, which is our mission,” said North Fork Audubon Society president Diana Van Buren. She organized the first Dragonfly Day four years ago and worked with environmental activist Lillian Ball and photographer Glenn Corbiere to create information panels about dragonflies at the pond’s edge.

Ms. Oliviera assists the New York natural heritage program, conducted by the Department of Environmental Conservation, in tracking dragonflies.

“I didn’t realize I would love it until I started doing it,” she said. She got involved because the heritage program promised to provide $1,500 worth of equipment. She was manager of the Kaler’s Pond Audubon Center in Center Moriches at the time and the offer seemed like a good deal.

Years later, she is still tracking and reporting on dragonflies and damselflies.

Damselflies are much smaller than dragonflies and can generally be found on the edges of a pond because they are weak fliers and flutter, while dragonflies zoom, Ms. Van Buren said.

What makes dragonflies particularly interesting for kids is that they can be captured in a net, put on a magnetic board for study and then released. But it takes talent to capture them because they have eyes that can span an almost-360-degree circle. The children enjoy putting them on their fingers, and while the dragonflies are swift in picking off mosquitoes, gnats and other flying insects, their mouths are too tiny to bite people, Ms. Oliviera said.

There are more than 20 dragonfly species on the North Fork, and although the adults have a short lifespan — about four weeks — they live for one to seven years below water in ponds in their nymph state before they finally emerge into full-fledged insects. Below water, they look like tiny hard-shell crabs, regularly molting old shells for new ones, until they finally come out of the water climbing plant stalks, where they stay and strengthen their wings until they’re able to take flight, Ms. Oliviera said.

Because dragonflies seek pristine fresh water, she advises people not to eat fish from fresh water sites where there are no dragonflies. The absence of dragonflies is an indication of possible pollution, she said.

Since dragonflies are cold-blooded, they need to warm up to fly, and that means at night they take to trees to rest, returning to the pond to fly when the sun is out. Toward the end of the day, when mosquitoes are often swarming, the dragonflies will be out in force to feast, Ms. Oliviera said.

The males also come to the pond when mature to inseminate the females while in flight. They’re very territorial and can often be seen hovering over the females, who lay eggs in the pond.

What’s unique about the Dragonfly Day program is that it has always proven popular with both younger and older children, Ms. Oliviera said.

“They become citizen scientists for the day,” she said.

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North Fork Audubon Society’s

Fourth Annual Dragonfly Day

1 p.m. Saturday, Aug. 14

Skipper Horton Wentworth Park

Route 25, Greenport

(just east of the Southold Information Center)