Mexican Fruit Fly Quarantine in Portion of Los Angeles County

Three Flies Detected in Long Beach

CDFA News Release

A portion of Los Angeles County, including the Los Angeles and Long Beach ports, has been placed under quarantine for the Mexican fruit fly following the detection of three flies, including two mated females, within the City of Long Beach. Mated females are significant because they indicate a breeding population that increases the risk of spread of this pest. CDFA is working collaboratively on this project with the United States Department of Agriculture (USDA) and the Los Angeles County Agricultural Commissioner’s Office.

The quarantine area measures 79 square miles, bordered on the north by CA-91; on the south by the Pacific Ocean; on the west by I-110; and on the east by Palo Verde Avenue. A link to the quarantine map may be found here: www.cdfa.ca.gov/plant/mexfly/regulation.html.

Sterile male Mexican fruit flies will be released in the area as part of the eradication effort. The release rate will be approximately 325,000 sterile males per square mile per week in an area up to 50 square miles around the infestation.  Sterile male flies mate with fertile female flies in the natural environment but produce no offspring. The Mexican fruit fly population decreases as the wild flies reach the end of their natural life span with no offspring to replace them, ultimately resulting in the eradication of the pest.  In addition, properties within 200 meters of detection sites are being treated with an organic formulation of Spinosad, which originates from naturally-occurring bacteria, in order to remove any mated female fruit flies and reduce the density of the population. Finally, fruit removal will occur within 100 meters of properties with larval detections and/or mated female detections.

The quarantine affects any growers, wholesalers, and retailers of susceptible fruit in the area as well as nurseries that grow and sell Mexican fruit fly host plants. Those businesses are all required to take steps to protect against the spread of the pest. At the Long Beach/Los Angeles ports, exports as well as imports may be impacted depending on specific circumstances. The quarantine will also affect local residents growing host commodities on their property. Movement of those commodities is not permitted. Residents are urged to consume homegrown produce on site. These actions protect against the spread of the infestation to nearby regions, where it could affect California’s food supply as well as backyard gardens and landscapes.

The Mexican fruit fly can infest more than 50 types of fruits and vegetables. For more information on this pest, please see a pest profile at: www.cdfa.ca.gov/plant/go/MexFly.  Residents who believe their fruits and vegetables may be infested with fruit fly larvae are encouraged to call the state’s toll-free Pest Hotline at 1-800-491-1899.

While fruit flies and other invasive species that threaten California’s crops and natural environment are sometimes detected in agricultural areas, the vast majority are found in urban and suburban communities.  The most common pathway for these invasive species to enter our state is by “hitchhiking” in fruits and vegetables brought back illegally by travelers as they return from infested regions of the world.  To help protect California’s agriculture and natural resources, CDFA urges travelers to follow the Don’t Pack a Pest program guidelines (www.dontpackapest.com).

New Medfly Quarantine

A portion of San Diego County was placed under Medfly quarantine earlier this week following the detection of 4 adult Mediterranean fruit flies (Medflies) in the La Mesa area.  The United States Department of Agriculture (USDA), the San Diego County Agricultural Commissioner, and CDFA are working collaboratively on this project.

The quarantine area in San Diego County measures 93 square miles, bordered on the north by Prospect Avenue; on the south by Mount Miguel Road; on the west by Fairmount Avenue; and on the east by Vista Grande Road.  A link to the quarantine map may be found here: www.cdfa.ca.gov/plant/medfly/regulation.html.

To eradicate the infestation, the release of sterile male Medflies began on August 10, at a rate of 250,000 flies per square mile per week.  The new release area is approximately 59 square miles.  In addition, properties within 200 meters of detections are being treated with an organic formulation of Spinosad, which originates from naturally-occurring bacteria in soil, in order to eliminate any mated females and reduce the density of the population. Finally, fruit removal will occur within 100 meters of detection properties in order to remove any fruit infested with eggs and larvae.

The quarantine will affect any growers, wholesalers, and retailers of susceptible fruit in the area as well as local residents. Home gardeners are urged to consume homegrown produce on site and not move it from their property.  These actions protect against the artificial spread of the infestation to nearby regions where it could affect California’s food supply and our backyard gardens and landscapes.

In the eradication program,  sterile male Medflies are brought to San Diego County from the joint CDFA/USDA sterile insect rearing facility in Los Alamitos, which prepares sterile files for release everyday over the Los Angeles basin.  The sterile release program has a proven track record of eradication in southern California.  Sterile male flies mate with fertile female flies in the environment but produce no offspring.  The Medfly population decreases as the wild flies reach the end of their natural life span with no offspring to replace them, ultimately resulting in the eradication of the pest.

The Medfly can infest more than 250 types of fruits and vegetables, causing severe impacts on California agricultural exports and backyard gardens alike.  Residents who believe their fruits and vegetables are infested with fruit fly larvae are encouraged to call the state’s toll-free Pest Hotline at 1-800-491-1899.