Mosquito Trapping in PWC

Mosquito Trapping in PWC

The Mosquito and Forest Pest Management Branch conducts regular monitoring of adult mosquito populations across the County. Surveillance is a key part of the Integrated Pest Management (IPM) strategy used to reduce and control mosquito populations. Over 130 traps are set weekly at more than 50 trap sites across the County from spring until fall.

Monitoring the variety of species requires the use of three trap types. Gravid traps, which look like a toolbox, use a lure of hay-infused water to attract female mosquitos looking to lay eggs. CDC light traps use a combination of light and a CO2 (carbon dioxide) lure to attract any mosquitos looking for a “blood meal.” CO2 is provided with cylinder gas tanks, emitting just enough to mimic human breathing. The BG Sentinel trap also uses CO2, along with a pheromone-scented lure to target species looking to feed on people.

Traps are collected 24 hours after being set. They are brought back to the branch lab where the mosquitos are identified and sorted by species. Samples are then pooled and sent to another lab where they are tested for West Nile Virus and any other arboviruses in the community.

Individuals may occasionally see these traps in the field; please to do not touch or interfere with them. For questions or concerns, contact the Mosquito and Forest Pest Management Branch at (703) 792-6279 or For more information, visit