State Should Learn to Live With Medflies, Experts Say : Agriculture: They call eradication efforts a waste, urge that other ways be found to protect produce industry.

The return of the Mediterranean fruit fly--the little insect the government has spent 17 years and more than $170 million trying to kill--is prompting some to suggest that the state stop swatting flies and start learning to live with them.

Since Sept. 8, 129 of the blue-eyed insects have been trapped in Los Angeles County, a number that rises sharply every day. What is most troubling about this infestation is its reach, breaking out in not one manageable pocket but five: Pasadena, Duarte, Griffith Park, Jefferson Park west of downtown Los Angeles and Inglewood.

Its vastness rivals the early days of an infestation that began in July 1989. What started with a single fly found in an Elysian Park peach tree soon erupted into the largest and costliest Medfly obliteration battle in Southern California history--lasting 16 months and costing $52 million.

Although officials say they have the weaponry to keep this outbreak in hand, some scientists are calling on the state to stop lurching from one infestation to the next and start researching ways to protect California’s $4.7-billion produce export industry if the Medfly wins the war.

“I always thought Californians were crazy not to learn to live with the Medfly,” said Ron Prokopy, a University of Massachusetts entomologist who has studied the insect for 20 years. “Farmers live with fruit fly pests all over the world. You don’t need to get rid of every single fly to farm effectively.”

The flies are turning up in some of the same areas where the state proudly pronounced them dead less than two years ago. This time, state and federal agriculture officials have vowed to use “only as a last resort” aerial spraying of malathion, the tactic that enraged Southern California residents in the 1989 outbreak.

Instead, work crews are releasing what will amount to billions of sterile Medflies in infested neighborhoods in hopes that the insect with breed itself out of existence.

“The public need not be alarmed,” said Los Angeles County Agricultural Commissioner Leon Spaugy, citing an ample supply of sterile flies and better traps.

But a look back over the nearly two decades since the first Medfly made its debut in Marina del Rey in 1975 suggests that the outbreaks are getting bigger and more frequent.

According to state officials and Medfly experts, this is the sixth consecutive year that the insects have turned up in California in numbers large enough to warrant an eradication program. A Medfly has been caught in one of every three cities in Los Angeles County since 1975. Their range extends from San Jose to Orange County and as far east as San Bernardino.

Some scientists are questioning whether the state should give up its obsession with killing every Medfly in California and focus on just keeping them out of the orchards.

They suggest “fly-free zones” like those used in Florida, which ensure an importing country that a particular orchard is clean even if the entire state is not. Another tactic scientists say has succeeded without the use of pesticides is harvesting certain produce early and letting it ripen in the warehouse, safe from Medflies.

“The issue is protecting California agriculture,” said James Carey, a UC Davis entomologist and member of the state’s Medfly Scientific Advisory Panel. “The state has to look at a long-term solution to a problem that is not going to go away.”

But agriculture officials are adamant that veering off the course of total eradication could cost California as much as $900 million a year, and endanger an economy that is limping from the recession. Japan, a leading importer of California produce, is said to be closely watching the infestation and officials fear that the Japanese will refuse California produce if the Medfly starts breeding out of control.

Hawaii, where the Medfly breeds rampantly, is estimated to lose tens of millions of dollars annually in such crops as avocado, mango and citrus it cannot grow because of the pest. The state’s leading exports--sugar cane and pineapple--are Medfly-resistant, said Roy Cunningham, science advisory panel chairman and a fruit fly expert with the U.S. Department of Agriculture in Hawaii.

“If the Medfly were established here, growers would have to change their entire cropping pattern. Hawaii does not grow some of the produce we grow simply because they can’t,” Spaugy said. “That is something none of us wants to face.”

The state’s eradication strategy has been controversial since the insect first landed in California. Former Gov. Edmund G. (Jerry) Brown Jr. refused to allow aerial spraying in a 1982 infestation and the ensuing uproar is said to have cost him a Senate seat.

But six years later, when the state’s helicopters poured 52,640 gallons of malathion over Southland homes for 100 nights, residents chanted in protest in the streets. The treatment dramatically reduced the Medfly population, but it also stirred complaints of health problems, sick pets and damaged paint on autos and nearly 300 legal claims.

Rather than risk a public revolt this time, state and federal officials have changed battle plans. In addition to the buzzing cardboard boxes of sterile flies being spilled in infested neighborhoods, crews are hand-spraying malathion in yards where the flies are thought to be hiding. More than 20,000 traps have been hung throughout 1,000 square miles of Los Angeles County in an attempt to define the limits of the infestation and stomp it out.

But no one can say whether the new strategy will work. The goal is to wipe out every one of the insects, which are less than a quarter of an inch long, across thousands of square miles of the Los Angeles Basin. Just one missed pregnant female can set off another infestation. And critics ask if aerial spraying--agriculture’s biggest gun--has failed to do the job, how can a few billion sterile flies do it now?

“I am not as confident as I would like to be,” said Richard Rice, a UC Davis entomologist and member of the science advisory panel. “A sterile fly release is not a sure-fire thing in an area this large.”

Government experts concede that the new protocol is risky, but a study by the health department and a message from the Legislature recommends aerial spraying only when all else fails.

“Spraying in my opinion is a safe procedure and unfortunately the public doesn’t view it that way,” Cunningham said. “Spraying certainly has a greater chance of accomplishing the mission. The sterile fly release has a greater chance of going wrong. But I’m still confident it will work.”

Officials carefully stop short of guaranteeing that the malathion helicopters will not fly again. The sterile fly program is up to four times more expensive than aerial spraying and the state budget is stretched to its limits.

Another disturbing aspect of this infestation is its reach. If the flies continue to show themselves in more communities, and there are not enough sterile flies or work crews to cover the territory, the infestation could warrant an aerial attack, officials said.

“If we should find these flies popping out all over the basin then we have to look at that alternative, as much as we don’t want to,” Spaugy said.

But the Medfly team says it has learned a great deal since the last war, when aerial spraying was at times so frenzied that the helicopters flew at the sight of a few insects.

A shortage of sterile flies forced aerial spraying then, they say. But two fly factories in Hawaii are churning out 650 million sterile males a week--enough to battle an infestation of 750 square miles, 40% larger than the last one.

And a new “sticky yellow panel trap”--said to be seven times more effective at luring flies--is better defining the infestation’s boundaries, officials said.

The combination of sterile flies, sticky traps and ground spraying of malathion appears to have controlled a San Jose infestation this summer without aerial spraying, officials said. Experts used the same methods after 25 flies were found in Koreatown a year ago and were on the verge of declaring that infestation eradicated when four flies were caught last month in nearby Jefferson Park.

“If not for those four flies, I would say we were 100% successful in Koreatown. With a little fine-tuning, we can make this work,” said Isi Siddiqui, California Department of Food and Agriculture assistant director, who oversees the Medfly eradication project.

But the endless emergence of “a few more flies” is precisely the reason some scientists wonder if the state’s goal of a Medfly-free California is feasible.

The notion of eradication came about in the days when the flies would disappear for years. But the Medfly is returning faster and more frequently than before, resurrecting a debate between bureaucrats and scientists as persistent as the insect: Has the Medfly made a permanent home in California?

Agriculture officials argue that they effectively wiped out the pest in 1989. It keeps showing up because people keep bringing in infested fruit, they argue, holding up as proof a blitz of inspections at airports and other points of entry that turned up fruit crawling with larvae.

“We pick up thousands of pounds of produce from innocent people who say: ‘I think I’ll send this papaya to Aunt Minnie,’ ” agriculture department spokesman Carl DeWing said. “In it we find all kinds of pests, including the Medfly.”

But some scientists say it is highly possible that the fly is “established” in California, a technical term meaning that it has taken up residence and that there is no getting rid of it.

What elevates the debate beyond the academic is California’s multibillion-dollar agriculture export industry, which depends heavily on produce on which the Medfly preys. To acknowledge that the Medfly is established here could prompt a devastating quarantine in the nation’s largest produce-exporting state.

Carey has long held the view--published last year in the journal Science--that the Medfly is established in California. Although he has been a lone voice in expressing this view, the current infestation has prompted some colleagues to acknowledge that he may be right.

“It’s highly possible that the Medfly never really was eradicated when it came to California and has remained in California as a low but continuing population,” said Prokopy, the University of Massachusetts entomologist.

But state officials cite the fly as testament to the success of their years-long insect battle. After a 1982 infestation in San Jose destroyed $200 million in produce, naysayers predicted 7,000 square miles of California would soon be crawling with Medflies.

“That did not happen,” said the agriculture department’s Siddiqui. He noted that California agriculture has since suffered no economic Medfly damage, a record he attributes to the state’s resolve.

In Hawaii, where the Medfly breeds with abandon, one flytrap can nab more than 100 flies in a day, he said.

“You can go into a back yard and not find a single peach that is not infested with maggots,” Siddiqui said. “Twenty-five flies in Koreatown is a far cry from that.”