Our Resident Entomologist Weighs In
The horsefly is the fastest insect reaching speeds of more than 90 miles per hour. There are more than 3,500 species of horseflies in the world. In many of those species the female must have a blood meal in order to obtain the necessary protein to develop her eggs, while the males only feed on nectar and pollen.
Black flies are small, rather squat, grayish or blackish with large rounded wings and a distinctly humpbacked shape. Adults are most common in Spring and early Summer and in forested regions these flies can be extremely annoying. The larvae attach themselves to rocks by means of a suction disk at the end of the abdomen in order to be near a stream with high oxygen count. None of the species in North America are known to transmit diseases, though some tropical species are known to carry a roundworm that can cause blindness in people.