Why is the government dropping millions of flies over the Bay Area?

"In response, the state started doing something that might seem strange: releasing millions more fruit flies out of airplanes every week to drift down upon the South Bay. (Close your mouth when looking up kidding!) But these flies are different. They're males that have been exposed to radiation to make them sterile. They breed with female flies, but no viable eggs result thus, the invasion is gradually eradicated."

"Though small, the danger they pose is real. Medflies can ruin more than 250 kinds of produce by infecting them with maggots. The department estimates that if the population were uncontrolled, it would cost the state's agricultural industry as much as $1.8 billion a year. Medflies are smaller than houseflies, but considerably more destructive. They attack more than 250 species of fruit, flowers and vegetables. (U.S. Department of Agriculture)"

A small number of invasive Mediterranean fruit flies were detected in San Jose this summer. The state responded by releasing millions of sterile male fruit flies from airplanes to mate with wild females, producing no viable eggs and gradually eradicating the infestation. The sterile-insect technique has been used successfully in Southern California and in Oregon, Florida and Louisiana. Mediterranean fruit flies attack over 250 species of fruit, flowers and vegetables and can carry maggots that ruin produce. Uncontrolled infestations could cost California's agricultural industry up to $1.8 billion annually. The flies are brightly colored, smaller than houseflies, and native to the Mediterranean.

Read at www.mercurynews.com