The most frequently collected mosquito in August was Culex pipiens, with an abundance close to average for the month of August. Another mosquito, Culex erythrothorax, has been trapped at far below average numbers (3.172 per trap-night compared to the five-year average of 18.381). This species breeds in marshes that contain tule (cattail) plants. The District treats larger tule marshes by drone or…

The District conducts intensive surveillance for invasive Aedes mosquitoes during the summer months. The surveillance program mainly targets two container-breeding species, Aedes aegypti and Aedes albopictus, which have been increasing their range within California over the last several years. The presence of these mosquitoes is highly undesirable because they are aggressive human biters and also…