Mosquito Larvae Surveillance and Control
Larviciding is done during the daylight hours and is the most effective method of mosquito control. More mosquitoes are terminated in their larval stage than in there adult stage. It only takes mosquitoes 3 to 7 days to go through their life cycle depending on temperatures. Technicians in the field use a GIS program developed for mosquito control. This program helps with the mapping, monitoring and recording of locations that require continuous mosquito control during the season. If mosquito larvae are present during a routine inspection then a larvicide is applied accordingly. Weekly monitoring of mosquito sources greatly reduce the occurrence of adult mosquitos in a given location.
Biological Control...At North Morrow Vector Control District we use gambusia affinius also called mosquito eating fish (pictured below) to help control mosquito larva in ornamental ponds, farm ponds (that have no access to the Columbia River)and stock troughs.
Adulticiding ...Also called fogging, is done during the evening hours. It is the last resort when it comes to mosquito control. Fogging missions are determined by our adult trapping numbers, presence of mosquito borne-disease and mosquito complaints from the public. Mosquito traps must meet a pre-determined threshold before a fogging mission can be executed in a specific area.