Surveillance is an essential part of an integrated mosquito management program. JCVCD uses surveillance to monitor mosquito sources, mosquito abundance, and mosquito-borne disease presence throughout our District.
Adult Mosquito Surveillance
Mosquito abundance and species composition are most often determined by monitoring traps at fixed locations year after year in addition to strategically placed “floater” traps. Each week from April-October, JCVCD monitors approximately 50 mosquito traps at fixed locations along set routes and dozens of floater traps set in areas where we suspect mosquito activity may be occurring. JCVCD primarily uses four types of mosquito traps:
Our trained field technicians inspect hundreds of known and potential mosquito sources every year for the presence of larvae. This is done by using standard dipping techniques to look for various stages of immature mosquitoes. If larvae or pupae are found, the technician determines and records the stage of development (instar) and the average number of larvae per dip. A larval sample will often be collected and reared in our lab to determine the exact species. Knowing the relative abundance, stage of development and species of larvae present helps us decide what control measures if any, need to be taken.
JCVCD monitors for mosquito-borne diseases like West Nile virus and Western equine encephalitis by sending adult mosquitoes collected in our traps to the Oregon State University Veterinarian Diagnostic Laboratory for testing. Although we collect a variety of mosquito species, our disease surveillance program focuses on mosquitoes from the Culex genus, which are our primary disease vectors.