Mosquitoes are a much-dreaded fact of summer throughout the world, but anyone who enjoys the outdoors in Canada and the northernmost U.S. states knows that the real enemy of the wilderness wanderer is the malevolent black fly.
Black flies, also known as buffalo gnats or turkey gnats, are small flying insects that feed off the blood of humans and other animals. Though tiny — they reach a maximum length of 1/8” when fully-grown — black flies are a formidable foe.
Most prominent beginning in about the middle of May, and continuing to make the outdoors a miserable place to be well into June, or even July, black flies do not spread disease among humans, though their bites are painful, itchy, and slow to heal. They can cause severe allergic reactions in some, up to and including death. Because black flies tend to swarm their prey, a single victim can receive numerous bites in a short period of time, increasing the likelihood of a dangerous reaction. For this reason, some U.S. states try to control black fly populations for public health.
Unlike mosquitoes, which breed in stagnant water, black flies lay their eggs in clean fast-running water, such as rivers and streams. Female black flies lay hundreds of eggs in or near the water, so they are very common in wooded areas near bodies of water.
Repelling Black Flies
Black flies can be difficult to repel. The simplest way to prevent getting bitten is to protect your skin by wearing long sleeves and pants at all times when outdoors. Because they are attracted to dark colors, it’s also a good idea to wear light-colored clothing, such as khaki, tan, or white.
One particularly annoying habit of black flies is their tendency to swarm the face. This occurs because they are attracted to the carbon dioxide we exhale. A good way to protect your face is to wear a hat with attached netting, specially designed to protect the head and neck from black flies.
Some recommended natural repellants include vanilla extract, lavender, and the extract from pine branches — just break open a young branch and rub the moisture from inside on your skin.
Avoiding wearing sweet smelling perfumes, and indulging in candy or soft drinks when outdoors can also help to reduce your risk of attracting black flies.
If you find that these home remedies are not effective, you may need to move up to a commercial insect repellent. Sprays containing DEET are often recommended, though their effectiveness against black flies is unpredictable — some even report that DEET sprays attract black flies. Repellents containing Permethrin are more likely to be effective, but they are also more toxic than DEET sprays, and can be harmful to fish, cats, and beneficial insects such as honey bees.
Soothing the Itch
If you do get attacked by black flies, there are a number of things you can do to soothe the itch. First, wash the affected area with soap and warm water, and avoid scratching the bites as much as possible. Scratching can break the skin, increasing the risk of infection. Applying topical agents such as aloe vera, witch hazel, or a gentle over the counter remedy, such as calamine lotion, can also help. If the itching persists, or is very bad, an antihistamine cream may be needed.