The Asian Tiger Mosquito (Aedes albopictus) is an aggressive day-biting mosquito native to Southeast Asia. It is an important vector of diseases such as Dengue fever, Eastern Equine encephalitis, and Chikungunya virus.
They were first found in the United States in 1985 near Houston, Texas and the mosquito has since spread rapidly through most of the southeastern United States. Despite multiple introductions to California, they were not established on the West coast. Last year, however, an invasion of these mosquitoes involved a large area (about 18 square miles) in southern California. The latest news about the southern California situation can be found at the San Gabriel Valley or Greater Los Angeles websites. Locally, the Santa Clara County Vector Control District (SCCVCD) has successfully eradicated two invasions of ATM in the past decade. In 2001, a greenhouse in Gilroy was infested by a shipment of “lucky bamboo” from Southeast Asia. Later, in 2003, ATMs were detected in a greenhouse in Mountain View, and had spread about a quarter mile outside of the nursery. The SCCVCD is monitoring the current situation in California, and asking residents to report if they find ATM in Santa Clara County.
How can I recognize ATM?
The adult mosquitoes are smaller than most of our local mosquitoes. They are day biters, and have a black body with distinct silver-white bands/strips on their legs, proboscis (piercing mouthparts), head, and body.
A local species, the Western Treehole Mosquito, is similar in size and also bites during the day, but it lacks the white strip on the back and is more drab in coloration. This species is usually prominent in areas with older trees, and is active from April through July. ATM may be active from spring to fall, and could occur in any urban or rural area.
Where does it breed?
The Asian Tiger Mosquito is known as a "Container Breeder" because it deposits its eggs in small containers rather than the larger areas used by most mosquito species. The eggs of the Asian Tiger Mosquito are glued to the sides of containers just above the water line, and hatch when the water level rises. The mosquito develops from larva to adult in about seven days. In southern California, experience indicates that they thrive in humid microclimates, such as dense collections of potted plants that are frequently watered.
What can you do to help control ATM in your yard?
Getting rid of standing water containers of any size is very important. Common breeding sites are on patios and in backyards. Residents are urged to do the following:
- Search for and discard any containers, cans, buckets, or old tires around the home.
- Remove any saucers from beneath potted plants and drill drain holes in all decorative flowerpots.
- Dump and drain any standing water around the home and wipe the containers thoroughly with a towel to remove any eggs.
- Do not store water in uncovered buckets or rain barrels. Ensure rain barrels are completely sealed to prevent mosquitoes from entering.
- Empty birdbaths and small fountains completely or clean them thoroughly every 3 days.
- Clean out rain gutters and lawn drains to ensure water does not collect.
- Water plants at the bottom near the soil, not the top.
- Regularly check gardens for potential breeding sites. Talk to your neighbors about preventing mosquitoes from breeding.
Who should I call if I find one of these mosquitoes?
If you are a resident of the County of Santa Clara and you think that you have found or are bitten by small, black-and-white striped mosquitoes during the day contact the SCCVCD at (408) 918-4770, fill an online request for service, or drop us a message at http://twitter.com/#!/SCCVCD. Those with digital cameras can send pictures and locations of specimens via email to email@example.com with “ATM” in the subject line. If possible, preserve the specimen until you get contacted by one of our technicians.