Deadline to End Spraying of Malathion in Jeopardy

State agricultural officials acknowledged Wednesday that a May 9 deadline to end aerial pesticide applications over Southern California neighborhoods infested with Mediterranean fruit flies is in jeopardy.

Rex Magee, associate director of the state Department of Food and Agriculture, said that two more sprayings beyond May 9 may be required over communities that since winter have been visited every three weeks by helicopters bearing malathion.

The deadline was announced earlier this spring amid intensifying opposition to the aerial applications. Officials want to switch to a more benign treatment: releasing millions of sterilized Medflies to breed the fertile population out of existence. The strategy calls for any new infestations to be sprayed once or twice with malathion and then treated with sterile flies.

A flurry of new outbreaks, however, has raised doubts about whether there will be enough sterile flies to accommodate the strategy. Experts are especially worried that the spring outbreaks are only a harbinger of an even greater explosion of Medfly activity when the weather warms.

“We are doing everything we can to find more steriles,” Magee said. “We still have a week to 10 more days before we make our decision. We may have to do one or two more treatments. . . . It is our only alternative.

“We are going to try everything we can not to use pesticide,” Magee said. “But we may well have to change plans tomorrow.”

Magee added that newly discovered outbreaks--including 103 square miles found to be infested in the last four weeks--most likely will have to be sprayed weekly at least eight times. Under the previous strategy, calibrated to the relatively dormant fly activity of winter, neighborhoods were sprayed only every three weeks.

Magee’s assessment echoed that of one of the state’s scientific advisers, who warned earlier this week that the May 9 deadline most likely could not be met.

Intensifying the sterile fly shortage are serious production problems at a new breeding facility in Hawaii and a Medfly outbreak in Florida, expected to siphon flies from California.

As state officials were scrambling to assess whether they will have enough sterile flies to meet the May 9 deadline, all five scientists impaneled to advise the Medfly campaign in interviews independently urged the state to abandon the strategy switch, which they have opposed from the outset.

The scientists, who will meet next week in Los Angeles to develop a uniform appeal, believe that because of the sterile fly shortage the malathion spraying should not be stopped.

“They’ve deluded themselves into thinking their plan will work,” said Roy Cunningham, the chairman of the Medfly Science Advisory Panel and one of the world’s top experts in Medfly eradication. “They’re in dreamland.”

Said James Carey, the panel’s most outspoken member who contends that undetected Medfly infestations have existed in Southern California for years: “Clearly we are at a crossroads and we have to take stock of the situation. . . . We are dealing with this week by week. And we haven’t seen anything yet.”

The scientists said they are nearly certain that the worst of the Medfly infestation will come in the summer, when Medfly breeding cycles quicken.

Most panel members agreed that one or two more pesticide applications in certain long-infested neighborhoods--Brea, La Habra, Glendora, Irwindale, Verdugo Hills and Garden Grove--would be enough to ensure the infestation was stamped out, thus eliminating the need for sterile flies in those sectors. This would leave more sterile flies to fight new infestations.

Magee, however, said the “state will do everything we can to live up to our commitment to use steriles” in all sectors infested before March 19, the day Agriculture Director Henry Voss announced the May 9 cut-off.

Since then, the availability of sterile fly supplies has become a complex game of juggling numbers and devising contingency plans.

Cunningham described the state officials’ scramble to meet the May 9 deadline as a self-made crisis.

“They’ve shot themselves in the foot,” he said.

The state’s eradication program requires the weekly release of 1 million steriles in every square mile of infestation. About 365 million sterile Medflies would be needed each week to completely stop malathion spraying throughout most infested sectors, scientists estimated. At best, state and federal breeding facilities can churn out about 340 million.

Contributing to the apparent shortfall are problems at the massive U.S. Department of Agriculture fly breeding plant at Waimanalo, Hawaii.

The new, high-tech plant is designed to eventually produce 500 million sterile flies a week and is now set to produce 100 million a week. But glitches have limited production capacity to about 40 million a week.

“We’ve got a big gap,” said Glenn L. Hinsdale, facility director. “Right now, it’s not the best, but it’s the best we can do.”

The state also maintains two sterile-breeding plants of its own in Hawaii and imports sterile flies from a Mexican facility jointly operated by the U.S. Department of Agriculture and Mexico. Magee said the state is negotiating with federal agriculture officials to obtain more Mexican-bred flies.

The number of malathion applications is set according to the anticipated breeding activity of the Medflies. The approach calls for continuing applications until two breeding cycles have passed without the trapping of any new flies.

Cunningham, who made a special tour of the Hawaiian facilities this week to assess the situation, said he intends to recommend that the state abandon the May 9 deadline and embark on the more flexible strategy, phasing out aerial spraying only in some sectors.

He said the state has only two options: Renege on the May 9 deadline, which would assuredly touch off vehement public outcry, or live with an eradication program constantly on the edge of crisis.

“The best thing the state could do is say, ‘Hey, we made a bad call,’ and get on with the program,” Cunningham said.

MEDFLY SPRAYING MAP: B2