Greenheads | Learn about Greenhead Flies, the Beasts of the Northern Wild
Meanwhile, I’m about to visit my first trap. I’m wading through thigh-high grass with Dr. Stoffolano and his wife, Susan, headed toward one of the greenhead traps alongside the road that cuts through the marsh around Pine Island. I’m wearing light-colored clothing, because greenheads zero in on dark, moving objects, and I’m covered head to toe, despite the blazing heat. We approach the first black box–it’s buzzing audibly.”That’s a sound you don’t want to hear,” Susan Stoffolano observes, as we peer through the thick screen on the top of the box, reinforced so that birds can’t tear it apart to get at the insects. Inside, the box is crawling with tabanids, and two interior troughs are littered with corpses. There’s no bait; the insects enter from below, fly up to the light, and then can’t figure out how to exit. (The Northeast Massachusetts Mosquito Control & Wetlands Management District installs and maintains the boxes, but lets Dr. Stoffolano remove flies as needed.)
Together, he and his wife unscrew a corner of the trap, drape towels over sections to direct the flow of insects, and position a mesh carrier over the opening. Low-tech, but it works. It quickly fills with live flies, and we move on to the next trap. A steady breeze blows, keeping us mostly fly free.
Listening to all this buzz reminds me of a story Dr. Stoffolano told me about how horses were once used on the marsh around Pine Island to help cut salt-marsh hay, which even today is prized by gardeners for inhibiting weeds: “They made nets out of ropes that completely covered the horse, so that as the horse moved, it would dislodge any tabanids that were trying to bite.” And even in modern times, rumor has it that sometimes the postmen around Newbury and Pine Island will balk at delivering the mail, because greenheads are attracted to the moving mail truck and get trapped inside with its unlucky driver.
So what’s a human to do? I ask the horsefly expert for any words of wisdom, recommendations, last-minute thoughts.
“If it’s the season of the fly in your area, you gotta wear light-colored, protective clothing,” he replies. “They can’t bite through your clothes. And I would suggest that more beaches post Web sites. If it’s a heavy day for greenheads, don’t show up at the beach; you’re wasting your money. Forget about it. If you’re a restaurant, and you don’t want people sitting outside to be bitten, then you put traps up.”
His hand flashes before me, and with a graceful swipe he captures a renegade greenhead, crawling on top of the trap. “They’re beautiful creatures, aren’t they?” he smiles. He’s gripping the insect in a sort of tiny Heimlich maneuver, so that it can’t bite him, and then he holds it up to my face for a closer look. I’m staring into a pair of huge (relatively speaking) green eyes. “Look at those eyes,” he marvels, and then releases it.
Two hundred more eggs, if she gets a solid meal, I think to myself. And we watch her fly away.