Horseflies are common large flying insects often encountered during warmer months. A frequent question arises regarding their interaction with humans: do horseflies bite or sting? Horseflies do not sting; instead, they inflict a painful bite.
The Horsefly’s Method: Biting
Female horseflies are the ones that bite, and they do so out of a biological necessity. They require a blood meal to obtain the protein necessary for the development and maturation of their eggs. Male horseflies, conversely, feed on nectar and plant fluids and therefore do not bite. Female horseflies use a cutting action, unlike the piercing mechanism of a mosquito or a bee’s venom injection.
Horseflies possess specialized mouthparts that function like miniature blades. These serrated structures cut into the skin of their host, rather than puncturing it with a needle-like proboscis. Once the skin is cut, the horsefly then laps up the pooling blood. This cutting action, combined with the lack of an anesthetic compound in their saliva, causes immediate and sharp pain.
What a Horsefly Bite Entails
When a horsefly bites, the sensation is an immediate, sharp pain, often more intense than other insect bites. This is due to their method of cutting the skin rather than a fine puncture. Following the bite, the affected area usually develops a red, raised welt.
A small bleeding point may be visible at the center of the welt, a direct result of the cutting mouthparts. Common reactions to a horsefly bite include localized itching and swelling around the bite site. While most bites are not dangerous, scratching can lead to secondary infections. Some individuals may also experience an allergic reaction, characterized by more extensive swelling or other symptoms.
Interacting with Horseflies
Identifying a horsefly can help in avoiding their bites. Horseflies are relatively large, stout-bodied flies, ranging from 0.25 to 1.25 inches in length. They are often recognized by their large, sometimes iridescent or brightly colored eyes, and their strong, fast flight. They tend to be most active during the day, particularly in warm, sunny conditions.
Preventing horsefly bites involves several practical measures. Wearing protective clothing, especially long sleeves and trousers, can reduce exposed skin. Avoiding areas with high horsefly populations, such as damp environments or near livestock, is also beneficial.
For treating a horsefly bite, clean the area with soap and water to prevent infection. Applying a cold compress can reduce swelling and discomfort. Over-the-counter anti-itch creams may alleviate itching.