Sterile Males Released in Medfly Battle

Four million sterile male Mediterranean fruit flies were released Tuesday in the San Fernando Valley, launching a massive birth-control program aimed at wiping out the crop-destroying pest in the area.

State agriculture officials expect to release 100 million to 300 million of the sterile male Medflies in the next two months to induce the insects to “breed themselves out of existence,” said E. Leon Spaugy, Los Angeles County agricultural commissioner.

“We will overwhelm the native population,” Spaugy said after lifting a cardboard bucket from a picnic table and letting a sample of 4,500 of the insects loose at a press conference at Louise Park in Van Nuys.

“These guys are promiscuous” and will mate with as many females as possible, decreasing the chances that females will find fertile males to mate with, said Thomas Palmer, coordinator of the eradication project for the state Department of Food and Agriculture.

Earlier Tuesday, crews on a roving truck turned loose 2 million sterile male Medflies in similar fashion over 28 square miles of the West Valley. Another 2 million flies were released from an airplane over a 62-square-mile area.

About 20 million sterile flies will be released this week, with that number increasing to as many as 40 million each week for the next two months, Spaugy said.

The sterile flies are dyed pink so that if caught in one of the state’s traps, they can be distinguished from Medflies already in the area, Spaugy said.

The sterile fly release is the second step of an eradication program that began last week with aerial spraying of the pesticide malathion over 16 square miles in the Northridge-Reseda area, where the first Medflies were discovered July 20. In all, six Medflies--three males and three females--have been found in the state’s traps.

The sterile insects are expected to head off the need for more aerial malathion spraying, despite the discovery of two immature male Medflies last weekend in a Reseda yard, Spaugy said.

The sterile fly release area corresponds roughly to the 62 square miles quarantined last week by the state Department of Food and Agriculture. Residents are not allowed to remove home-grown fruit from the area, which has a jagged boundary defined roughly by the Santa Susana Mountains on the north, De Soto and Corbin avenues on the west, the Ventura Freeway and Victory Boulevard on the south and Woodman Avenue on the east.

The cost of the eradication effort is expected to be “in the neighborhood” of the $2 million spent last year to fight an infestation in East Los Angeles, Spaugy said.