Spraying for black flies begins

Aerial spraying will continue on both sides of the Delaware River on a weekly to bi-weekly basis.

By: Concetta Benuzzi-Volpe
   WEST AMWELL — Township officials are urging residents to take common-sense precautions during the spraying of this year’s crop of pesky biting black flies.
   The Pennsylvania Department of Environmental Protection May 14 began spraying the banks of the Delaware River with the pesticide Vectobac, officials said.
   Aerial spraying is an annual occurrence and will continue on both sides of the river on a weekly to biweekly basis through September, depending on the severity of the problem, DEP officials said.
   According to DEP, the use of the pesticide creates minimal risk to the general public but it is obliged by law to notify all New Jersey municipalities affected by the spraying. Specific times and dates are available to the public by calling the Hunterdon County Health Department.
   At the Township Committee meeting May 21, Committeewoman Nance Palladino suggested local residents could be better informed as to the possible risk potential involved with aerial spraying.
   The New Jersey DEP’s Pesticide Control Program’s Black Fly Suppression Program works in concert with the Hunterdon County health department.
   According to Hunterdon County’s Mosquito Vector Control Program Coordinator Tadhgh Rainey, the two main breeding sources for the gnats commonly called black flies in the county are the Delaware River and South Branch of the Raritan River.
   "DEP is responsible for treating the entire contiguous Delaware River system while the health department treats the Raritan River," Mr. Rainey said.
   Benjamin Russell, New Jersey DEP water pollution biologist for the southeast regional office, said the zone to be treated extends south from just below the Delaware Water Gap to the northern limits of Trenton, also occurring at areas in between.
   According to Mr. Russell, treatment process is dependent upon weather, wind, temperature and monitoring the larvae population, making precise application dates difficult to determine.
   "When it rains or the water level is high, we can’t sample or treat the area," he said. "But Mr. Rainey at the health department is always notified prior to treatment. In turn, he posts the new information on the county Web site."
   Ms. Palladino briefly discussed the program at the meeting, suggesting local officials would like to help inform residents who may be unaware of treatment being performed within their residential boundaries.
   New Jersey DEP regulations require community wide notification be made by posting public notices at all boat ramps along the Delaware River and by publishing notices in local newspapers prior to spraying.
   But Ms. Palladino suggested coverage might not be enough to garner enough public attention to the possible risks associated with not being aware of the pesticide application.
   "It occurs to me that our residents should know the very side banks of the river will be chemically sprayed for gnat control," Ms. Palladino said. "Kids do play on the shorelines, and there are reactions that people may have to the spraying of Vectobac."
   According to the United States Environmental Protection Agency, Vectobac is slightly toxic with minimal potential risk to people when used properly as part of a complete mosquito control program.
   The larvicide is registered with the EPA and the DEP, which makes it legal to use in New Jersey.
   According to the agencies, Vectobac is an approved biological agent containing the soil bacterium, bacillus thuringiensis israelensis, that tends to break down rather quickly in the environment, usually within a few hours.
   Pennsylvania runs the largest single black fly program in North America.
   Hellicoptor Applicators Inc., a private contractor from Gettysburg, is supervised by the Pennsylvania DEP and permitted by the New Jersey DEP Pesticide Control Program to conduct treatments through aerial applications in Hunterdon County.
   The program, entitled the Delaware River Project, is operated as a cooperative effort between the two DEPs, Rutgers University and affected counties in both states.
   Black flies, wretched little gnats that hatch in mid-April, usually make their first appearance in May, swarming, biting and annoying humans and animals alike, causing a nuisance until mid-September.
   The gnats, have four stages of development, egg, larva, pupa and adult.
   According to the DEP, larval and pupal stages are spent in clean, oxygenated flowing water. Adult females then deposit their eggs in rivers, streams and creeks, developing over various times of the year. After emerging from the aquatic stages, adult flies mate, and females (only females bite) fly off seeking their first blood meal.
   According to Mr. Rainey, a brood of black flies can come off the river and fly as far away as 15 miles in search of a meal, creating a nuisance in many neighboring townships far from the river.
   "Typically, the flies do not bite along the river," he said. "They tend to fly pretty far away from their breeding area to feed, and that is something we would like to look into in the future."
   According to Mr. Russell, spraying adult flies is ineffective so Vectobac is used as a larvicide preventing the larvae from hatching in rivers and streams, acting on the immature stage before a flying adult can emerge.
   According to the Pennsylvania DEP, the use of the pesticide creates minimal risk for the general public, however, there are a few simple guidelines to follow.
   The DEP suggests avoiding exposure as the safest course of action, particularly for populations considered to be at higher risk, such as pregnant women, children, the elderly and those with chronic illness.
   Possible exposure risk can be reduced by following some common sense actions:
   • Plan to limit time spent outside during times of possible pesticide treatment.
   • Avoid direct contact with water bodies that have been treated.
   • Remove toys from application areas.
   • Remove animals and their food and water dishes from application areas.
   • Stay away from application equipment.
   The symptoms of exposure to Vectobac include mild irritation or discomfort with direct contact with eyes or skin.
   According to the Pennsylvania DEP, the chance of experiencing symptoms of exposure is low. Officials suggest anyone experiencing symptoms following a pesticide spraying should contact a physician or the New Jersey Poison Information and Education System at (800) 222-1222.
   For updated Hunterdon County application information, call (908) 788-1329 or contact Mr. Rainey at (908) 788-1351 to report a problem area.
   To further investigate this topic, residents can access the Hunterdon County Health Department Web site at www.co.hunterdon.nj.us/health.htm.
   Pennsylvania residents can access the state’s Web site at www.state.pa.us/ — keyword black fly — and follow the links or by calling the DEP’s southeast regional office at (610) 832-6059.