Mosquito Control season to begin
next week with spraying wooded wetlands

DOVER (March 16, 2011) – Weather permitting, DNREC’s Mosquito Control Section will start its annual spring woodland-pool spraying during the week of March 21, treating wooded wetlands near populated areas in New Castle, Kent and Sussex counties. Approximately 7,000 to 12,000 acres with woodland pools where early season mosquitoes breed in quantity will be strategically larvicided by helicopter and possibly aircraft.

If larval stages of these early season mosquitoes are not successfully controlled, an intolerable number of biting adult mosquitoes could take wing by early to mid-May and remain through late June, becoming particularly troublesome within one to two miles of their woodland pool origins, and significantly affecting local quality of life for residents and visitors alike, said Mosquito Control Administrator Dr. William Meredith. As in past years, only woodland pools near populated areas will be treated.

“Delaware has about 100,000 acres of wet woodlands and it is not possible logistically or for budgetary and environmental reasons to larvicide all woodland mosquito-rearing habitats,” said Dr. Meredith. “Targeting the pools near populated areas is the best return-on-investment in providing mosquito relief to the most people.”

Over the next few weeks, Mosquito Control will apply a bacterially-produced insecticide, Bti. “Like all insecticides used by the Section, the U.S. Environmental Protection Agency has determined that Bti, when used in accordance with all EPA-approved instructions as required by federal law, can be applied without posing unreasonable risk to human health, wildlife or the environment,” said Meredith.

The amount of spraying needed is determined by where the woodlands are and how wet they are, which can vary from year to year depending on the location and amount of precipitation that has occurred over the past autumn, winter and early spring.

Aerial spraying of woodland pools must be completed before the forest canopy fills in with leaves, usually around mid-April, because leaves prevent the insecticide from reaching pools and other wet spots containing larvae on the forest floor. The spring campaign marks the beginning of Delaware’s mosquito season, which in most years continues until sometime between mid-October and early November, depending upon when the first killing freeze occurs.

As in the past, advance public notice of when and where spraying will occur this year will be given daily via radio announcements, by calling 800-338-8181 toll-free, or by visiting www.dnrec.delaware.gov/fw/services/MosquitoSection.htm. Interested parties may also subscribe to receive email notices by visiting the DNREC homepage - click on “Email List Subscription” under Services and follow directions to sign up for mosquito control spray announcements.

During mosquito season, the public is encouraged to do its part to reduce mosquito-rearing habitat by cleaning clogged rain gutters, keeping fresh water in birdbaths, draining abandoned swimming pools and emptying standing water from such containers as scrap tires, cans, flower pot liners, unused water cisterns, upright wheelbarrows, uncovered trash cans, depressions in tarps covering boats or other objects stored outside.  

To request local relief, call Mosquito Control’s field offices:

·         Glasgow Office, 302-836-2555, serving New Castle County and the northern half of Kent County including Dover

·         Milford Office, 302-422-1512, serving the southern half of Kent County south of Dover and all of Sussex County.

For more information about Delaware’s Mosquito Control program, call the Dover office at 302-739-9917.

The Delaware Mosquito Control Section provides statewide services to more than 880,000 residents and more than 2 million visitors annually to maintain quality of life and protect public health by reducing the possibility of mosquito-borne illnesses such as West Nile virus. Throughout the warmer months, Mosquito Control monitors and treats mosquito populations that emerge from wetland areas found throughout the state, including ditches, stormwater ponds, wet woodlands and coastal salt marshes. The Section also works year-round on water and marsh management projects designed to reduce mosquito populations, and provides the public with information on dealing with mosquitoes, from reducing backyard breeding to avoiding mosquito bites.

Vol. 41, No. 95