EDITOR'S NOTE: The aerial black fly (gnat) suppression operation scheduled for Tuesday, June 17, on the Delaware River and the Lehigh River has been canceled because of weather conditions. A new date wasn't announced.
BETHLEHEM, Pa. — A helicopter flying over the Lehigh Valley will deploy treatments to tamp down black fly populations.
The helicopter, a Bell 206 Long Ranger, tail number N660HA, has scheduled flights in Bucks and Northampton counties, according to a news release from Northampton County officials.
Spray operations, through the state Department of Environmental Protection, are scheduled for the Delaware River, between Slateford in Northampton County to near Trenton, New Jersey/Yardley, Bucks County; and the Lehigh River at the Easton Dam at the confluence of the Delaware River.
‘Not a chemical’
The helicopter will spray Vectobac 12AS, a Bti product manufactured by Valent Biosciences.
“Bti is short for Bacillus thuringiensis var. israelensis, which is a bacterial larvicide, not a chemical, and is the only product used in Pennsylvania's waterways for black fly suppression,” according to the release, describing Vectobac 12AS as a brown liquid with a fish oil odor.
Flying low, near the tree top level, the helicopter will release the Vectobac at various predetermined positions on each river. It is not toxic to fish or other aquatic organisms.
“Please note that this work does NOT involve a helicopter spraying over the entire county, and applications will only occur on the specific waterways listed in this notice."Northampton County officials
“Please note that this work does NOT involve a helicopter spraying over the entire county, and applications will only occur on the specific waterways listed in this notice,” officials said in the release.
“Black flies, also known as biting gnats, are considered a pest that can inundate people seeking outdoor recreation in the warmer months, especially around rivers and streams.”
The 40th year
This year’s round of the state’s Black Fly Suppression Program began in April.
“Black flies are about 1/8" 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.”
There are 35 counties in the state’s suppression program, including both Lehigh and Northampton counties. Officials monitor and treat 48 rivers and streams, spanning more than 1,800 miles.
“As the weather turns warmer, Pennsylvanians will be spending more time outdoors, and black flies (biting gnats) are a pest that can put a damper on an otherwise beautiful day,” DEP Acting Secretary Jessica Shirley said in a news release.
“This annual treatment program reduces this nuisance so that Pennsylvanians and visitors can fully enjoy outdoor activities.”
Black flies have been a recognized pest of humans and livestock in Pennsylvania since the 1970s.
In its 40th year, the program focuses on the larval stage of a black fly’s life cycle in rivers. Officials do not conduct spray operations on land to control black fly adult populations.
For more information about the Black Fly Suppression Program, go to the DEP’s website.
