Mediterranean Fruit Flies Threaten Los Angeles Crops

Officials believe that residents bringing back produce from another country may be why "Medflies" were detected in Los Angeles.

The California Department of Food and Agriculture is taking precautions after Mediterranean fruit flies, commonly known as the "Medfly," were found in Los Angeles.

One adult male and five unmated female flies were found between March 3 and March 12, and four larvae were found in backyard fruit on March 18.

The Medfly was last detected in LA County in Lennox in Nov 2011. If Medflies are not eradicated, it could harm California’s $43 billion agriculture industry. The use of pesticides on fruit would increase and food prices would increase as well, according to the CDFA.

As a result, the CDFA has declared an 88-square mile quarantine in central Los Angeles near the University of Southern California.

"We're breaking the breeding cycle of this particular fly. We're also reducing the population of the flies that are here currently," LA County Deputy Agricultural Commissioner Max Regis said.

Members of the California Conservation Corps in Los Angeles went door-to-door removing fruit from trees in the affected residential areas Friday, as well as from properties within 100 meters of where flies were detected.

In addition to fruit removal, 250,000 sterile male Medflies were released in an effort to stop breeding.

"The release of sterile Medflies is a proven method of eradicating an infestation. The key is to move swiftly and take action before the pests can cause widespread damage and become established," CDFA Secretary Karen Ross said in a statement.

The Medfly can infest more than 250 types of fruits and vegetables, including apples, apricots, avocados, bell peppers, figs, grapes, grapefruits, lemons, limes, melons, nectarines, oranges, peaches, pears, persimmons, plums, pomegranates, tangerines, tomatoes and walnuts.

According to the CDFA, the life cycle of the Medfly begins when the adult female pierces the skin of fruits and vegetables and lays from one to ten eggs per fruit. The eggs hatch and develop into maggots, which feed on the fruit pulp. Decaying, infested fruit usually falls to the ground and the maggots leave the fruit and burrow into the ground to pupate. Adult Medflies emerge from the ground and mate, completing the cycle.

The Mediterranean fruit fly is native to Africa, but has spread to other parts of the world including southern Europe, Australia, and the New World tropics.

"We are finding that homeowners are sometimes bringing things back from countries that they visit so most likely this was introduced by someone bringing something back they shouldn't have brought and a medfly hatched from there," Regis said.

The CDFA advises people to not bring uninspected fruits, vegetables or plants from outside of California into the state.

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