Mosquitoes, Rats and Other Pests in San Diego: Who to Call

Mosquitoes, rats and similar pests are not a City of San Diego service. They belong to the County of San Diego Vector Control Program, part of the County's Department of Environmental Health and Quality. The County describes it as a countywide program that monitors vectors, meaning insects or other animals that can spread disease to people, and the diseases they carry. It covers residents inside the City of San Diego as well as other cities and unincorporated areas.

The County's vectors and other pests page says the vectors it monitors include mosquitoes, rats, mice, ticks, flies and eye gnats. For other pests, including bedbugs, cockroaches, fleas, kissing bugs, lice, mites, scorpions and spiders, the County says they are outside the program's authority: it offers educational information but does not control or regulate them. Bees are handled by a different County department, covered below.

The County says its Vector Control Program is funded mainly by a service charge and a benefit assessment that appear on property tax statements each year. The inspections and mosquitofish described below are listed as free.

The County's Request Service page is used to request a free rat or mosquito inspection or to report a green pool, a dead bird, high mosquito activity or another vector-related issue. You can reach the program these ways:

• Online. The Request for Service form asks for your contact details, the request type (mosquitoes, rats/mice, neglected or green pool, dead bird or other), a description and the problem location. The County says contact information is kept confidential, but if you leave it out you will not get updates on your request. The County's Tell Us Now! app (Android and Apple) also takes requests.
• Phone. (858) 694-2888. The office is at 5570 Overland Ave., Suite 102, in Kearny Mesa, and lists hours of Monday through Friday, 8:00 a.m. to 12:00 p.m. and 1:00 p.m. to 4:00 p.m.
• Email. vector@sdcounty.ca.gov. Include your name, phone number, the address of the problem and a brief description. If you want to report a problem in your area but do not need an individual inspection, the County asks you to say so.

The County says all mosquitoes lay their eggs in or near standing water and can go from egg to biting adult in a week or less, so finding, dumping and treating standing water is the best way to control them. Its prevention checklist says mosquitoes can lay eggs in as little as a bottle cap of water, and that even after all breeding sources are removed it may take about a week to see fewer adult mosquitoes.

• Green or neglected pools. The County's green pools page asks you to contact Vector Control if you notice a green swimming pool in your neighborhood or know of a foreclosed or unattended home with a pool. Technicians will treat the pool to prevent mosquito breeding; the treatment does not change the pool's appearance but reduces mosquito numbers. Include your name, phone number and the pool's address. The County also uses aerial surveillance to find green pools.
• Free mosquitofish. The County gives out free mosquitofish for green swimming pools, fountains and ponds at its Kearny Mesa office and at nurseries and pet stores around the county. It says you only need a few at first, to call the location ahead to check stock, and to contact Vector Control to set up a delivery if you need more than 5. Mosquitofish are for backyard sources only and should never go into lakes, streams, rivers or creeks.
• Drains, gutters and other water at home. The County's drainage page says even 1/4 inch of water at the bottom of a drain or pipe can breed mosquitoes, and calls lawn drains and French drains a very common source. It suggests cleaning gutters, flushing drains, fitting fine mesh under drain covers, and treating water you cannot dump with a bacterial larvicide, following the label.
• Invasive Aedes ("ankle biter") mosquitoes. The County's invasive Aedes page describes small black and white striped mosquitoes that bite during the day, especially around the legs and ankles, and are most active in San Diego in summer and fall. They were first found in the county in 2014, breed indoors and outdoors in small containers, and their eggs can survive for months in dry containers. The County advises dumping standing water inside and outside at least once a week, checking buckets, birdbaths, plant saucers and children's toys, and using fine mesh screens.
• Salt marsh mosquitoes near the coast. The County's salt marsh mosquito page says these aggressive biters breed in coastal wetlands after exceptionally high tides, can fly more than 10 miles, and do not transmit diseases in San Diego County. It says Vector Control treats these habitats by hand and, during peak season, from the air.
• What the County treats. The County's mosquito treatment page says technicians check and treat places like marshes, ditches and unmaintained pools with larvicides, treat over 1,500 smaller water sources by hand or truck, and use a helicopter for large sites during the mosquito season (April to October). When adult mosquito treatments are needed, the County says residents of affected areas get at least 24 hours' notice.

The County says West Nile virus is spread to people by infected mosquitoes, which pick it up from infected birds, and that Vector Control monitors it by testing mosquitoes and dead birds. Its West Nile virus page lists recent positive birds by location.

• Which birds the County collects. The County's dead bird page lists crows, ravens, jays, hawks, owls and falcons. Birds must be adults that have been dead less than 24 hours: not stiff, no ants or flies, no foul odor, intact with no injuries, and eyes intact. Do not freeze the bird.
• How to report it. Call (858) 694-2888, email vector@sdcounty.ca.gov or submit the online form. The County's request page says to call (858) 505-6657 on weekends, holidays or outside business hours.
• State reporting. The California Department of Public Health takes dead bird reports year-round through its online form at westnile.ca.gov. As of October 16, 2026, it says most agencies have stopped collecting and testing dead birds for the rest of the year, though some test year-round, and that reports are still useful for tracking the virus.
• If the bird cannot be tested. The County says not to touch it with bare hands: wear gloves or use a shovel, double bag it, and wash your hands with soap and warm water immediately afterward. For a dead animal on a City street or sidewalk, see our dead and stray animals guide.

The County's rats page says rats are found in all areas of the county and that roof rats, which climb rather than burrow, are the most common type here. Signs include droppings, gnaw marks, rub marks, sounds in the attic or walls, bark stripped from plants and piles of gnawed fruit, nuts or empty snail shells.

• A free educational inspection, not pest control. The County's rodent exclusion and control page says Vector Control offers free educational rodent inspections to county residents, done on the outside of buildings. They include a Rat Control Starter Kit with a tamper-resistant trapping station (snap trap and key), a brochure and a sample of 1/4-inch hardware cloth. The County says it is not a pest control company and does not trap, bait or remove rodents, including gophers or squirrels, and does not sell or provide poison bait.
• Keeping rats out. The County says rats can get in through holes the size of a quarter and mice through holes the size of a dime. It suggests sealing gaps with hardware cloth, trimming trees and bushes at least 4 feet from the roof, keeping garbage cans covered, picking ripe fruit, feeding pets in daylight and removing leftovers, and cleaning up fallen bird seed.
• Traps, bait and clean-up. The County recommends snap traps. It says poison bait should be used only outdoors, never indoors or under the house, and that baiting is illegal without a tamper-proof bait station. When cleaning up droppings, it says not to sweep or vacuum, but to spray a disinfectant (or 1 part bleach to 9 parts water), let it sit 15 to 20 minutes, and wipe up while wearing gloves.
• Trash that attracts rats. Missed collections and overflowing bins are covered in our trash and recycling pickup guide, and dumped trash piles in our illegal dumping guide.

• Ticks. The County's ticks page says tick-borne diseases such as tularemia, Lyme disease and spotted fevers are rare in San Diego County. Vector Control collects ticks along hiking trails for testing; it does not test ticks that have bitten people, but can help identify a tick you found on yourself or a pet. If you develop a rash or fever within several days to weeks after removing a tick, the County says to see your doctor.
• Flies. The County's flies page says Vector Control offers educational fly consultations but does not trap, bait or remove flies. Its advice is to remove breeding sources: keep garbage can lids tight and clean the cans, keep manure piles dry, flat or covered, get rid of grass clippings or keep them dry, and keep compost piles tightly covered.
• Eye gnats. The County's eye gnats page asks residents to report eye gnat problems to Vector Control at (858) 694-2888 or by email, with the date, time of day, location, approximate number of gnats and weather conditions.
• Bees. Bees are handled by the County's Department of Agriculture, Weights and Measures, not Vector Control. Its wild bee page says the County cannot remove wild honey bees from private property and advises against removing them yourself; contact a licensed pest control or live bee removal company. The County's who to call about bees flowchart says removal on private property is the owner's responsibility, renters should contact their landlord or property owner, and wild bees on City-owned property go to the city where they are located. Questions about beekeepers go to the County's Apiary Program Bee Hotline at 1-800-200-BEES (2337).
• Africanized honey bees. The County's Africanized honey bee page says the entire county, from desert to coast, is considered colonized by Africanized honey bees, that bees are most active in spring and fall, and to stay away from colonies. If you are attacked by bees, call 911.

The City does not run a vector or pest control service, but some of the problems that come with pests are City issues:

• Standing water in a City storm drain or street. A clogged or flooded City storm drain is a City stormwater problem. See our storm drains and flooding guide. If the water is breeding mosquitoes, you can also report it to County Vector Control, whose form takes public locations.
• Dead animals. Removing a dead animal from a City street is a City service; see our dead and stray animals guide. For a fresh dead crow, raven, jay, hawk, owl or falcon, call Vector Control first so it can be tested.
• Trash and dumping. See our trash and recycling guide and illegal dumping guide.
• Rental housing conditions. The City's Building & Land Use Enforcement lists uninhabitable living conditions and substandard housing conditions among the building complaints it investigates. Its page does not list pests as a separate category. See our code enforcement guide.

For other problems you can report to the City, see our guide to reporting a problem to the City of San Diego.