FRESH WATER AERIAL LARVICIDING

General:  Aerial fresh water larviciding is a site specific application of an insecticide to a fresh water wetland to control mosquitoes in there aquatic stages before they emerge as adult mosquitoes.

Notification:  A Legal Notice will be published in February of each year giving general information about the applications and contact information for questions. The actual dates and times of applications is determined by surveillance data.  Local health Departments and the Massachusetts Pesticide Bureau will be notified prior to each application and a press release may be issued.

Pre-treatment Surveillance:  In the spring,  potential mosquito breeding areas are surveyed prior to aerial application.  Numerous random  sample dips are taken to determine the specific location of mosquito breeding and population densities.  Ideally, aerial applications are scheduled upon finding uniform distribution of early larval stages.  Sample dips are recorded and compared with post-treatment survey to determine efficacy off the application.

Application:  When pre-treatment surveillance indicates an application is necessary,  granular Bacillus Thuringiensis var. israelensis (Bti) is applied by helicopter.  Bti  is a selective, naturally occurring, biological larvicide and is non toxic to people, birds, fish, bees, and nearly all other insect species.  Bti effects mosquito larva and a few other closely related aquatic insects in the fly family.

Post-treatment Surveillance:  Mosquito breeding areas that have been sprayed will be surveyed 24 hours after the application.   Numerous random sample dips will be taken and compared with pre-treatment surveillance data to determine the overall efficacy of the application.