Apart from the occasional deer, there are turtles, assorted birds, mice, and, once in a while, a rabbit, a raccoon, or an otter, mostly just passing through.
She has just laid her first batch of eggs. Her first blood meal. By doing so, she ensures that the precious bloodline will continue, that the next generation of greenhead flies—as she is more commonly known—will be born. A brilliant blue sky stretches overhead; a faint breeze ruffles the grasses. Perfect beach weather. A great day to fly. Her dazzling green eyes casting about, she makes a beeline for the water.
The sand up ahead is swarming with warm, scantily clothed bodies, fairly bursting with reservoirs of succulent human blood. He slides open a window and points to a squashed bug taped to the side of the building.
You may want to think about it. Like most beachgoers, tabanids prefer warm, sunny days, and it is, of course, an especially beautiful July morning, without even a hint of breeze. The sun is already fierce, the distant sand shimmers with promise, and the sea is as blue as the Aegean. But a face-off with greenhead flies? Do I want to spend a day swatting these things? I squint at this poster child for a bad day at the beach, weighing the pros and cons.
In full knowledge that at this very moment, a similar scenario is playing out, up and down the East Coast. Or at the very least, somewhere far from the coastal salt marshes.
But above and beyond these physical characteristics, and the fact that greenhead flies will indiscriminately attack horses, cows, dogs, hogs, and deer, this fly is notorious mainly for one thing: the pain it inflicts in large numbers on beachgoers at the height of summer.
Make that two things, because like The Terminator, this fly is relentless. It will not stop until someone pays the price. Stories of encounters with greenheads have a dramatic quality usually reserved for plays written by one-name ancient Greeks. But the blunt truth is that these creatures can ruin a day, or days, at the beach.
Often during peak greenhead season—generally early or mid-July to mid-August—beaches will post warnings about fly conditions, like some weird variation on the surf report.
There are no immune spots. Can greenheads be outsmarted? What makes them so rabid in the first place? Why is the pain so fierce? Every summer, Dr. Stoffolano and his students head into the dark heart of greenhead territory—the broad and glorious salt marshes that spread out around Pine Island, in Newbury, Massachusetts, not far from Crane Beach.
Here they collect thousands of flies from the shiny black wooden boxes that stagger on slender legs across the marsh, like dark, square animals imagined by a Cubist carpenter. Back at UMass, they conduct research on greenhead behavior and physiology. Stoffolano told me when I first visited his office in Amherst, months earlier. Bookshelves overflow with the chaos of his profession—research materials, scientific papers many his own , and reference books—the contents spilling onto the floor, the desktop, any available surface.
In sharp contrast to its occupant, who is neat, self-contained, and, it turns out, pretty funny, with an adventurous streak.
Tales of tsetse flies in South Africa, encounters with biting beach flies in the Seychelles, and experiences at a Zulu healing ceremony weave in and around talk of greenhead flies. His mother is part Mohawk Indian, and Dr. Traces of Indiana Jones, minus the bullwhip. Over the next few hours, I get a crash course in greenhead flies: Tabanids , if you will. Stoffolano insists. But once the female lays her eggs, her whole behavior changes.
She becomes extremely aggressive. Unlike the delicate mosquito, which is a vessel or capillary feeder, drawing blood much like a syringe does, tabanids are pool feeders, meaning they sever lots of capillaries at once, in order to create a gaping wound so that the blood can pour out.
Over and over and over. At first, according to Dr. As soon as they release saliva, which is a foreign protein, our bodies react to it and we sense pain.
The very thing she does so well keeps her forever hungry: The viciousness of her bite practically guarantees that it will be difficult for this insect to get a good meal. Stoffolano says. The traps are nuisance control. Which is still better than nothing, he acknowledges. Greenhead adults live three to four weeks, so the population builds up.
And although on a good day a greenhead can lay up to eggs in what may be her first and last reproductive act, these dark, heavy traps—painted black to mimic large animals, like cows—can attract and capture up to 1, greenheads per hour. The insects themselves are too big to eliminate without using massive amounts of pesticides, which would damage the delicate salt-marsh habitat. Besides, greenhead flies play a couple of important roles within that fragile ecosystem.
First, as an indicator of marsh health. The environmental conditions dictate the emergence and development e. The season is from June to September with the highest densities occurring the last two weeks of July to the first week of August.
Because of their predaceous nature as larva a significant reduction in number could produce a trade-off in species produced. For example, if greenheads did not keep the deerflies in check that problem could possibly become greater. Conventional methods of biting fly control are either environmentally undesirable or economically impractical.
Because of the large size of the larva and adult it would take a higher concentration of fairly toxic pesticides to control them and thus adversely affect other non-target organisms. Burning the marshes, water management, ditching or impoundments have been found ineffective and costly. Therefore at this time the most environmentally and economically solution to the greenhead fly problem is the proper trapping on the salt marsh.
For a number of years our research and development has been directed toward abatement of nuisance levels along beaches, recreational areas, and housing. In we began developing a box trap which has been modified many times and will probably be subject to other changes from year to year as we attempt to increase its effectiveness. In fact, traps capture large numbers of blood seeking flies, and if such traps are located on the marsh may serve as a control for greenheads.
Why are flies attacking me at the beach? The bites you may experience while lounging at the beach are usually the work of little pests known by a variety of names such as horse flies, midges or No see ums.
Biting flies can also sense the carbon dioxide we give off as well as lactic acid our body naturally emits. What is greenhead season? Peak greenhead season is from mid-July to mid-August, although they can appear in early July. Greenhead flies are a variety of horsefly. Like horseflies and deerflies, they slash a hole in the skin and feed from the resulting pool of blood.
How do you ward off Green heads? From the shore local to the seasonal tourist, they all have their theories on how to ward off the bloodthirsty greenhead. Some of these include using garlic supplements, a mix of Listerine and water, a mix of vodka and citronella, DEET with dry gin, and Skin So Soft — alone or mixed with mouthwash.
What are strawberry flies? The next insect to arrive on the scene in June depending on the weather is the strawberry fly. These flies are usually around NJ during strawberry season and have a pinkish color. The notorious greenhead fly usually comes in July.
It is known for its green head, hence the name greenhead. Where do Greenhead flies come from? Greenhead flies, named for their large, bright green eyes, can be found in the coastal marshes of Eastern North America. Get ready Scream! Greenhead flies are fairly resistant to pesticides.
People have tried for decades to poison greenhead flies. The flies for the most part just laugh at you. Humans have not done a good job of eradicating Greenhead flies. This is mostly true because we did not understand them well. Those poor attempts at poisoning them resulted in a few deaths. We killed off the weaker flies and what remains are the ones that have a resistance to pesticides. If you want to get rid of greenhead flies, then try the Fly Cage. It is a trap that works on many levels.
The result, which is not toxic, is that the greenheads fly in and never fly out.
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