Medfly Quarantine Area for Fruit, Vegetables Expanded in South Bay : Infestation: Sterile males are also being released after pregnant fly is found in Wilmington.

State officials have expanded a quarantine on home-grown fruit and vegetables and started releasing sterile male Mediterranean fruit flies in the South Bay, broadening a pest-control effort that began with the discovery last month of a pregnant fruit fly in Wilmington.

The quarantine area grew last week by 100 square miles, expanding to 1,110 square miles in Los Angeles, Orange and San Bernardino counties. Cities within the newly added zone include Wilmington, Carson, San Pedro and parts of the Palos Verdes Peninsula.

“The female (fruit fly) has a little appendage that she sticks under the skin of the fruit to lay her eggs,” said Carl DeWing, a spokesman for the state Department of Food and Agriculture. “To the average person, the fruit may look perfectly good. But if they move it out of the area, it could start another point of infestation.”

Agricultural officials face a quickly growing infestation that threatens to become one of the largest in Southern California’s history. State officials placed a record 1,300 square miles under quarantine during a massive infestation in 1989-90.

The quarantine prohibits the transport of home-grown fruits and vegetables within or out of the area unless they are frozen, cooked or canned. To dispose of fruit or vegetables, residents are asked to place them in double-lined plastic trash bags tied at the top.

Quarantine violators face fines ranging from $75 to $1,000.

State officials decided to expand the quarantine area after finding a pregnant female fly in a trap Nov. 29, near Avalon Boulevard and M Street in Wilmington. A week later, authorities sprayed the pesticide malathion within 200 meters of the find. No more sprayings are planned for the area, said MyrlysL. Hollis, a spokeswoman for the food and agriculture department.

Spraying, however, was scheduled to begin Friday in Compton and Hollywood, where officials found two more pregnant females in traps over the weekend. Authorities expect to spray in those communities at least two more times over the next month. Residents who do not want to be exposed to the pesticide may request an exemption.

Because of controversy over aerial pesticide spraying, state authorities now rely on ground spraying and the release of sterile Medflies to combat infestations of the pests. Although radioactively sterilized Medflies have been used for more than a decade, some scientists believe the technique is ineffective with this species of fly.

The idea is to saturate an infested area with sterilized males in the hope that they will mate with wild females, who would then produce no offspring.