Large, robust Horse Flies are perfectly sized for their irksome feeding habits on both equine and human targets.
Horse Flies, also known as Gadflies, are super-sized flies that excel at aggravating livestock and people. Though adults mostly drink nectar and plant juices, female Horse Flies need protein in order to produce eggs. Blood is the source of this protein and it can come from horses, cows, sheep, rabbits, or even people. The bite from a Horse Fly female can be felt right away, creating a red bump. Victims usually swat at the fly to scare it away after feeling the bite, but in a relentless pursuit for a blood meal, many female Horse Flies refuse to leave a target and doggedly pursue it even if it tries running away. For centuries, Horse Fly behavior and bites have been so bothersome that they are mentioned in classic literature, myth, and song.
Horse Flies are active during the day and rest at night. They do not like darkness, so they are rarely seen in forests and woodlands. Pastures that offer shady groves help livestock escape from the attention of Horse Flies. Lagoons and ponds also allow animals to stay submerged, reducing the number of places where a Horse Fly can bite. Horses and other animals are often seen using their tails to swat at flies trying to feed on their back and legs. Some blood-borne pathogens can be transmitted from animal to animal through a Horse Fly bite; some treatable diseases like tularemia can be passed from animal to human. For this reason, livestock herders and cattlemen try to protect their animals from the fly by using Horse Fly traps and building shaded shelters.
Unlike smaller House Flies, Horse Flies are not fuzzy or hairy. All Horse Flies have large eyes. In females, they are separated by a space; in males, they touch each other. This species has a black body and brownish, transparent wings. It also has a black dot on the wing along with some dark marks near it. The spiky, short antennae at the front of the face are an orange-red color. Females lay fertilized eggs that hatch within a week. Other types of flies and even some wasps parasitize the larvae, which can help control a Horse Fly population size, certainly a skill appreciated by all.
Scientific Name: Tabanus proximus
Fly or Mosquito
Size (Adult; Length): 15mm to 26mm (0.59in to 1.01in)
Colors: black, orange, brown
Descriptors: flying, biting, large, big, brown wings, dot, orange antennae, big eyes
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