Another step in mosquito control is surveillance. State or local mosquito specialists conduct surveillance for diseases harbored by domestic and nonnative birds, including sentinel chickens (used as virus transmission indicators), and mosquitoes. Mosquito control authorities also conduct surveillance for larval habitats by using maps and aerial photographs, and by evaluating larval populations. Other techniques include various light traps, biting counts, and analysis of reports from the public.
Mosquito programs also put high priority on trying to prevent a large population of adult mosquitoes from developing so that additional controls may not be necessary. Since mosquitoes must have water to breed, methods of mosquito prevention may include:
- Controlling water levels in lakes, marshes, ditches, or other mosquito breeding sites
- Eliminating small breeding sites if possible
- Stocking bodies of water with fish species that feed on larvae
- Employing chemical and biological measures to kill immature mosquitoes during larval stages.
Neighborhoods are occasionally sprayed to prevent disease and nuisance caused by large numbers of mosquitoes. The typical pesticides sprayed for mosquitoes are larvicides and adulticides.
If you have any questions about mosquitoes in your area, contact your local mosquito control district or health department.
Larval Stage Mosquito Control
Larvicides target larvae in the breeding habitat before they can mature into adult mosquitoes and disperse. Larvicides used to control mosquito populations include:
- Bacillus thuringiensis israelensis
- Bacillus sphaericus
- Mineral oils
- Monomolecular films.
Oils and films disperse as a thin layer on the surface of the water, which cause larvae and pupae to drown. Liquid larvicide products are applied directly to water using backpack sprayers and truck or aircraft-mounted sprayers. Tablet, pellet, granular, and briquet formulations of larvicides are also applied by mosquito controllers to breeding areas.