Oriental Fruit Fly Discovered in Thousand Oaks : Agriculture: Officials have stepped up trapping. The pests could threaten the citrus and avocado industries.

A trap set by Ventura County agricultural officials has snared an Oriental fruit fly, a pest that could threaten the area’s multimillion-dollar citrus and avocado industries.

Agricultural Commissioner Earl McPhail said Monday that a male Oriental fruit fly was discovered last week in a trap placed at a private Thousand Oaks home on Tennyson Street.

Because the fruit fly multiplies rapidly, “it is one of the most devastating pests that we could find,” Deputy Agricultural Commissioner Ann McClure said. But she said “it’s easier to eradicate than the Medfly. That is one advantage.”

The Oriental fruit fly kills crops by laying eggs under the skin of fruit and vegetables. After the eggs hatch, maggots tunnel into the fruit or vegetable and leave their droppings behind.

County agricultural officials have stepped up trapping in an 81-square-mile area around the spot the fruit fly was found. The number of traps was increased from 332 to about 800, officials said.

The discovery of a female fruit fly could accelerate an eradication program, McClure said.

However, unlike the eradication effort against the Mediterranean fruit fly, the campaign against the Oriental fruit fly would not involve malathion spraying, officials said.

“We’re checking those every day and making sure that we don’t find another one,” McPhail said. Traps will be checked daily for the next week to find other fruit flies, particularly fertile females. After that, the traps will be checked weekly for three months until the danger of infestation is past.

It is the second time in two years that the pest has been found in Ventura County. Last Oct. 27 an Oriental fruit fly was found in the city of Ventura, McClure said.

But the Oriental fruit fly has spread throughout Southern California this summer. Ventura County is the third county in the state where the fly has been found, said Gera Curry, a spokeswoman for the state Department of Food and Agriculture.

The Oriental fruit fly was also discovered in Los Angeles and Riverside counties, and officials have recently completed or are about to complete eradication programs there, Curry said.

Although less devastating than the Medfly, the Oriental fruit fly threatens about 230 fruit, vegetable and nut crops grown in California.

“Many of them are not only grown in California, but are major crops here,” Curry said.

The fly has been eradicated using a bait laced with a chemical pesticide. The pesticide, dibrom, is mixed with a lure that attracts and kills male flies.

Meanwhile, county agricultural officials have not ruled out the possibility of a quarantine. But a quarantine would not be instituted unless a second fly is found, Agricultural Commissioner McPhail said. A quarantine would prevent fruit grown within the county from being sent outside the area, he said.

The discovery of an Oriental fruit fly put one of the largest lemon growers in the county on alert.

Chris Taylor, vice president of farming for Limoneira Associates in Santa Paula, said company officials had feared the encroachment of more devastating pests such as the Medfly or a Mexican fruit fly, more than the Oriental fruit fly.

However, Limoneira officials will be monitoring the situation to ensure the Oriental fruit fly does not spread, he said.

“We’ll keep abreast of the problem,” Taylor said. “It’s one of the three fruit flies that are a threat.”