Delaware Initiates Annual Spring Mosquito Spraying Campaign in Forested Wetlands
Sussex County, DE - The Delaware Department of Natural Resources and Environmental Control will commence the annual spring spraying of woodland pools to control aquatic immature mosquitoes.
Treatments are scheduled to begin as soon as Friday, March 20. The campaign will continue through mid-April, depending on weather conditions.
Spraying operations by the Mosquito Control Section will initiate in southern Sussex County. These operations will expand into Kent and New Castle counties over the subsequent weeks.
The targeting of early-season woodland pool larvae is conducted to limit the emergence of biting adult mosquitoes in early May.
Up to 10,000 acres of wet woodlands near populated areas are authorized for annual treatment. Recent drought conditions have reduced surface water areas in forested wetlands.
Additionally, colder winter temperatures delayed mosquito egg hatching. The first mosquito larvae of the season were documented at the end of February. These environmental factors are monitored closely to determine optimal treatment schedules.
All control treatments will be executed via helicopter. A liquid, bacteria-derived insecticide known as Bti will be applied. The application is timed to coincide with the mid-larval aquatic life stage.
The U.S. Environmental Protection Agency has determined that Bti poses no unreasonable risks to human health, wildlife, or the environment when applied according to federal guidelines.
This woodland spray campaign marks the beginning of the statewide mosquito control season, which typically concludes in late October. Control activities will expand in April to manage saltmarsh, freshwater, and urban container-breeding mosquitoes. These efforts are implemented to protect public health and maintain the state's quality of life.
Information regarding scheduled spraying locations and times can be obtained by calling 800-338-8181. Notifications are also available via email, text, or voicemail by subscribing to the Spray Zone Notification System at de.gov/mosquitospray.
Local mosquito control services can be requested by contacting regional field offices. The Glasgow Office (302-836-2555) serves New Castle County and northern Kent County, including Dover. The Milford Office (302-422-1512) serves southern Kent County and all of Sussex County. Further details are provided at de.gov/mosquito.
