A Mediterranean fruit fly infestation centered in the Santa Monica area of Los Angeles County has been eradicated, ending a quarantine that began in late 2009.

The eradication of this infestation, along with the recent lifting of two similar quarantines in northern San Diego County, means California is now free from Medfly infestations. As a result, residents, growers and  farmers market vendors previously subject to the quarantines may now move fruits and vegetables without restrictions for the pest.

“Whether you are a farmer or a backyard gardener, fruit flies can pose a significant threat to your harvest,” said CDFA Secretary A.G. Kawamura. “Eradicating these infestations takes a great deal of coordination and cooperation by growers, residents and agricultural officials within the quarantine areas, and I’d like to thank all of them for their help.”

To eradicate the pest, agricultural officials employed weekly aerial releases of approximately 2.5 million sterile Medflies over the core of the quarantine area.  Fertile female flies in the environment mate with the sterile male flies but produce no offspring, ultimately resulting in eradication of the pest. The sterile Medflies were brought in from the joint CDFA-U.S. Department of Agriculture rearing facility in Los Alamitos, which prepares hundreds of millions of sterile flies weekly for release over the Los Angeles Basin, where the pest has been introduced repeatedly by international travelers who bring infested produce with them.

The Mediterranean fruit fly is one of many pests that threaten both agriculture and residential gardens in California. As travel and commerce increase worldwide, the variety and frequency of pests breaching our border are also on the rise.

The pest can infest over 260 types of fruits and vegetables, threatening California’s crops and exports as well as our urban and suburban landscaping and gardens. A permanent infestation would result in estimated annual losses of $1.3 billion to $1.8 billion.

Even with the recent success with the Medfly, CDFA is still regulating more than 60 thousand square miles under quarantine due to the presence of eight different invasive species.