Discovery of Medfly in Downey to Expand Spraying Target Area

A fertile Mediterranean fruit fly was reported Tuesday to have been detected in Downey, expanding an already large swath of residential neighborhoods in Los Angeles County targeted for at least one dose of aerial pesticide spray.

The fly, found late Monday and flown to Sacramento where its fertility was confirmed, significantly stretches to the south the county’s worst Medfly infestation. So far, the outbreaks have been largely contained in the San Gabriel Valley.

But the Downey find and another last week in the Orange County community of Brea have further complicated eradication efforts, stretching resources to the limit and prompting officials to warn residents that their neighborhoods probably will be subjected to two or more aerial applications of the pesticide malathion.

Meanwhile, three helicopters lifted off Tuesday night from El Monte Municipal Airport to spray malathion over a 23-square-mile area of the San Gabriel Valley encompassing Rosemead, South El Monte, Monterey Park and San Gabriel.

The recent Santa Ana winds could be contributing to the spread of the Medfly problems, said Roy Cunningham, an entomologist and leading member of the state’s scientific advisory panel on the Medfly. He has conducted studies in Hawaii that show that the quarter-inch-long fly has been carried up to eight miles by island trade winds.

“We are hoping these winds settle down,” Cunningham said. “This fly is a weak flier. But in an open stretch it can be carried for miles.”

The Downey discovery represents the “last straw” in the state’s ability to fight the Medfly by releasing sterile flies to breed the population out of existence, Cunningham said. Even the billions of sterile flies being purchased from Mexico will not be enough to cover the Downey infestation, he said.

“This definitely means we have exceeded our capacity to . . . flood all areas with sterile flies,” Cunningham said. “There is a limit to what we can handle.”

Next week, the scientific panel will meet with state and county officials to revamp current eradication strategies, which do not appear to have checked the escalating Los Angeles County infestation.

On Tuesday, County Agricultural Commissioner Leon Spaugy remained optimistic.

“If we began picking up flies in Rolling Hills or Topanga, I would be very concerned,” Spaugy said. “I’m concerned now, but I’d be extremely concerned. That would indicate it is pretty much throughout the county. But we have stayed in pretty much the same area.”

The new 16-square-mile territory that will be sprayed Dec. 7 takes in Bellflower and Downey. There are currently no plans to apply more than one dose to the area, Spaugy said. But the state’s science advisory board could order more spraying after the meeting next week.

So far, 193 Medflies have been found in the county since August, and 174 square miles have been sprayed or are to be sprayed next week.

MAP OF SPRAYING AREA: B2.