Medfly Program Threatened by Shortage : Eradication: Once again, breeding labs can’t deliver enough of the sterile insects. It could force a resumption of malathion spraying in some areas.
The state’s plan to eradicate the Mediterranean fruit fly with the release of millions of sterile Medflies has been shaken for the second straight week by a shortage of sterile flies, raising the possibility of renewed malathion spraying, according to some of the state’s scientific advisers.
The shortfall, caused by production problems at three breeding facilities in Hawaii, has left the eradication program with a third fewer sterile flies than needed.
Several of the scientists advising the state said officials have only two options if the shortage continues: Redistribute the available sterile flies throughout the 343-square-mile treatment area or resume malathion spraying in some spots now being treated with sterile flies.
“The bitter pill to swallow is to revert back to spraying,†said one adviser. “I know they (agriculture officials) are not ready to swallow it, but that’s the only pill left.â€
But Isi Siddiqui, the assistant director of the state Department of Food and Agriculture and the man in charge of the eradication program, said the department has no plans for renewed malathion spraying at this point and remains opposed to it, except in the case of new fly discoveries.
He refused to say whether that policy would change if the shipments of sterile flies continue to fall short.
On Thursday, the state conducted its final anti-Medfly spraying in Los Angeles and Orange counties with a flight over Garden Grove.
At the height of the aerial war, the spray zone encompassed 536 square miles. It now stands at 48 square miles, covering parts of the city of San Bernardino and the Riverside County community of Woodcrest. Spraying those areas is scheduled to continue through June.
The shortage of sterile Medflies was discussed at a meeting of the state’s five-member Medfly Science Advisory Panel on Friday.
The advisers--all entomologists--have been told by agriculture officials not to comment on their discussions. But several members said privately that they believe the shortage is serious and will be difficult to correct soon.
The state is “fiddling around with fly deliveries that are never met,†one adviser complained. “They’re kidding themselves.â€
Richard Rice, one of the panelists, said last week that some areas are being treated with far fewer sterile flies than the scientists consider acceptable. Sterile flies are released by the millions to make it virtually impossible for wild flies to find a fertile mate.
The dilution of the treatment program could pose a threat by opening a “window of opportunity†for the Medfly to breed, Rice said.
The panel arrived at no recommendations Friday, but has scheduled another meeting June 8 to review additional information from the state and come up with a possible plan of attack.
A final decision would be left to Henry J. Voss, director of the state Department of Food and Agriculture.
Los Angeles County Agricultural Commissioner Leon Spaugy, a co-director of the eradication program, stressed that there may not have to be any changes if sterile fly shipments pick up.
The state now needs about 343 million sterile flies a week--about 1 million for every square mile in the treatment zone.
When shipments dropped to 221 million last week, Siddiqui said the shortage would be quickly corrected with the arrival of an extra 80 million sterile flies from a breeding facility in Mexico.
But in the meantime, production dropped even further at the three Hawaiian facilities, leaving Southern California with only about 242 million sterile flies this week.
Despite such setbacks, Spaugy said, the lack of Medfly discoveries for the past month is an encouraging sign that the shortage of sterile flies has resulted in no new problems so far. But, he added, “We’re going to be reviewing the program and reassess the situation.â€
Spaugy said eradication workers will provide the panel with a series of options on how to redistribute the available sterile flies, such as shrinking some treatment zones or concentrating the releases in core areas.
Resuming malathion spraying in some areas would be the “last resort,†he said.
Pat Minyard, deputy Medfly Project director, said: “The department’s position is that we’re not going to go back into malathion bait treatment. We’d take a political bath on that, boy.â€
He acknowledged that some members of the advisory panel believe more spraying is inevitable, but said they are not the majority.
Asked the chances for more spraying, Minyard replied, “Zero to none. . . . I don’t think it’s going to happen.â€
