EASTON, Pa. — For the second time this season, Northampton County officials on Thursday are deploying treatments to tamp down black fly populations.
- Black fly treatments begin Thursday in Northampton County
- It's the second time this season county waterways have been treated
- Officials use a bacterial larvicide, not a chemical, to tamp down populations
The state Department of Environmental Protection will treat Bushkill Creek from Easton to Tatamy, according to a news release from Northampton County officials.
Officials were slated to begin spraying from bridges over the creek or while wading.
There are 37 counties in the state’s Black Fly Suppression Program, including Lehigh and Northampton, and it involves monitoring and treating 1,700 miles of 48 rivers and streams across the commonwealth.
Lehigh River, which this year was added to a list of endangered rivers across the United States, and the Delaware River both are listed as treated rivers.
Swatting them is useless as they are quick to return, often flying into people's eyes and sometimes delivering a painful and itchy bite.Pennsylvania Department of Environmental Protection
“Black flies are about one-eighth inch in length, and are much smaller than a house fly,” according to the state DEP. “They are often referred to as gnats and they have the annoying habit of swarming around the heads of people on warm days.
“Swatting them is useless as they are quick to return, often flying into people's eyes and sometimes delivering a painful and itchy bite.”
Treatment not toxic
The last treatment, in June, used a white Bell OH58 helicopter with blue and red stripes. DEP personnel were on site at all landing zones, managing the operation.
“It is a bacterial larvicide, not a chemical, and is the only product used in Pennsylvania's waterways for black fly suppression. B.t.i. is not toxic to fish or other macroinvertebrates found in the treated waterways, and it degrades quickly in the environment.”Northampton County news release
Officials will use Vectobac 12AS, manufactured by Valent Biosciences, to treat the rivers.
“The B.t.i. material is a naturally occurring bacteria (Bacillus thuringiensis israelensis) that kills the immature (larval) form of the black fly when they feed on it in the waterways,” according to the news release.
“It is a bacterial larvicide, not a chemical, and is the only product used in Pennsylvania's waterways for black fly suppression.
“B.t.i. is not toxic to fish or other macroinvertebrates found in the treated waterways, and it degrades quickly in the environment.”
Black flies have been a recognized pest of humans and livestock in Pennsylvania since the 1970s.
