Black Flies Reported, Already

Biting black flies (Diptera: Simuliidae) have been abundant in several recent years.  We’ve received our first reports of the season, but it’s too early to know if this will be another “outbreak” year. Stay tuned.

Black flies, AKA buffalo gnats, are most common along rivers and streams where the larvae can develop in the clear, running water.  However, adults flying in search of hosts can be found up to 8 miles from the river.

Black fly females feed on blood from humans, wildlife, livestock, and poultry by puncturing the skin.  Reactions to the bites vary from an annoying puncture to swelling and itching at the bite site to headache, nausea, and fever.  Black flies are not known to transmit disease agents to humans in the U.S. 

Control of black flies is not practical.  Treating rivers and streams to kill larvae, and fogging large areas to kill adults, are not advisable.  See


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