Greenhead flies are notorious for their annoying and painful habit of biting residents of the northeast during the summer months. These flies are particularly abundant in coastal areas where they attack beachgoers, fisherman, dock workers and even swimmers in large swarms. Greenhead flies are also abundant around homes that are located near salt marshes, horse stables, and barns inhabited by livestock. At the moment, greenhead flies are not out biting beachgoers, but the insects are expected to arrive in a month or so, and luckily, pest control professionals are confident that the insects will be well controlled.

Greenhead fly season lasts from June until September, but they typically appear in large numbers toward the beginning of July. Areas of Massachusetts that are located farther south, such as Saugus and Manchester, see the arrival of greenheads a few weeks earlier than northern areas. The flies are problematic all along the northeast states and into New York. The most frequent and largest sized swarms occur during the latter half of July and during the first week of August. Male greenhead flies do not bite, but females inflict painful bites that release saliva that acts as an anticoagulant to prevent excessive bleeding at bite wounds. Females are most active from the morning hours, usually 10 AM, until dusk.

Greenhead flies are not easy to control, but this year officials are placing more greenhead traps than usual around populated coastal areas, especially beaches. These traps use an insecticide that smells like the breath of a cow in order to lure the insects into the death-trap, as greenheads are attracted to this particular scent. It is important to keep in mind that greenhead flies are attracted to darker colors, particularly black and blue. Therefore, it is not advisable for coastal residents or beachgoers to wear black and blue-colored clothing. While greenhead fly traps are effective at reducing populations, this insect, like most fly species, is difficult to control.

Have you ever visited the beach during a season when greenhead fly swarms had been abundant?