CALIFORNIA COMMENTARY : Los Angeles Is Home Sweet Home : Medfly: There is virtually no chance that each of the hundreds of new catches represents a new infestation. The first outbreak, years ago, was never eradicated.

Well, friends and fellow citizens, the first battle in the Medfly war--the epic struggle that began 15 years ago--is over. We’ve lost. We have lost abysmally, ignominiously and unconditionally. The Huns are pouring into Rome. The Russians are swarming over Berlin. Malathion has not worked. The sterile flies have not worked. Humiliation. We have to face reality. We have to step back and reassess. Any ecologist who is not employed by the state or federal governments, who looks to biological truth for guidance, not to political mandate, will tell you the same thing.

What, then, is going on--what is really going on behind the biological scene? James Carey, an entomologist at UC Davis, has taken on that question. As a university scientist, his job and his reputation depend on finding the biological truth. He therefore began with the most elementary step in data analysis, looking for gross patterns in whatever evidence that existed; he just added up the Medflies caught in Los Angeles County each year. What he found has revolutionized the Medfly story.

It begins in 1975, with the first outbreak of 34 flies, and, according to the state, it was eradicated. No more flies appear for five years. Then, four flies show up in 1980 and 53 more in 1981. Again the Medflies are eradicated, according to the state and federal governments. Of course, one fly happens to be caught in 1982, one in 1984, one in 1986, but these are just the odd bug, declares the government. Nothing to worry about. Easy to eradicate. . . . Until 1987. Forty-four turn up then. That population is also eradicated. Fifty-three arrive in 1988. Yet another successful eradication. A resounding 241 enter the traps in 1989, incredible in light of the fact that the flies have been eradicated in eight of the previous 13 years. But by now it has become routine to eradicate them. The government has become so good at eradication that there is no need for alarm; they can do it any time. They are not about to “let” the Medfly immigrate illegally.

In the minds of the government bureaucrats and their in-house scientists, each year’s outbreak is a new invasion. Without realizing it, they have fallen victim to a fundamental function of the human mind: illusion. The mind creates illusions of life; illusion is the explanation of the images that move across the screen of the conscious mind. The problem is, illusions are crafted around one’s interests. You see the world in a way that supports your job. All your research is right-headed, all your methods work.

There is also denial. The mind instinctively ignores facts that run against its illusions.

So, tourists, immigrants and illegal aliens are said to be sneaking infested fruit into Los Angeles and lobbing it, presumably, into the various neighborhoods as they drive by. With drive-by lobbings out of control, what more could go wrong? There is talk of fruit-fly terrorism. A $10,000 reward is offered for information leading to the arrest of any miscreant. But for some inexplicable reason, no one is able to claim this prize. And there it is, the drive-by, fungus-spore, sterile-duped, malathion-suckered, state-controlled Medfly.

A very different explanation occurs to Carey, the ecologist whose mandate is to find biological reality. When, like the government agents, you are defending a cause, you bend the truth to fit the illusion. When, like Carey, your mandate is to find the truth, you bend the illusion to fit the facts.

What Carey sees is not an endless series of new introductions. It is an absolutely classic, textbook example of a single, massive invasion. He applies the discipline known as “invasion biology,” a field in its own right, for insects do strange and remarkable things when they acquire new territory.

A typical insect invasion has four phases: There is the introduction, when the first colonists arrive; there is colonization, in which they reproduce; then naturalization, in which the insect calibrates its body and adjusts its behavior to its adopted land, and, finally, the spread phase, in which, remodeled and finely tuned, it multiplies and marches, multiplies and marches and settles down in those regions to which it is genetically suited. Carey claims, and he is undoubtedly right, that the Medfly has entered that fourth and final phase.

There are some crucial points to be emphasized here.

First of all, Phase 3--naturalization--is a critical and difficult time for an insect. It is not easy to get a toehold in a new land. It arrives suited for life in the place it left, and like a human immigrant, it has a sort of biological “accent.” Also like the human immigrant, its offspring will become native speakers and natural citizens. The only difference is that the insect takes a number of generations, for its adjustments are genetic. It must adjust to different pathogens, different strains of food with different levels of minerals, and so on. And, if pesticides are used heavily against it, the insect must acquire some kind of resistance, some way of coping with them, because they are part of the new environment. Malathion bait is part of the Medfly’s new home, a big part.

To get some idea of how difficult it is for insects to adapt to a new land, entomologists have been introducing beneficial insects deliberately for more than 100 years, and only about 30% of the species have ever established themselves. And these were given every advantage--matched to similar environments, released in huge numbers, put in sheltered places, provided with food, shielded from pesticides.

The point is, Medflies are not like fungus spores or plant seeds. Infestations do not sprout wherever an infested fruit rolls to a stop, which most likely would be the garbage can. There is virtually no chance that each of the new catches represents a new infestation.

Furthermore, Medflies are being caught in the same neighborhoods where they were caught eight years ago. At least four of these sites were heavily sprayed with Malathion. The odds of new infestations occurring on top of old ones cannot be calculated, literally.

Finally, if, for the sake of argument, tourists, immigrants and aliens were importing fruit, and if the flies were sprouting like seeds as the government claims, then you would expect infestations throughout Southern California. Especially in San Diego, with its river of immigrants flowing northward. Southern and Central California would have gone up in a huge Medfly conflagration long ago. Until this last month, all of the captures have been in the Los Angeles area.

The truth can be denied, but it cannot be altered: The Medfly is established. Almost certainly it has been among us since 1975 and has never been eradicated. The chances are excellent that it arrived even earlier, as long ago as the mid-1960s.

How The County Tried To Kill A Fly The number of medflies found in Los Angeles County each year. 1975: 34 ‘76: Eradication claimed ‘80: 4 ‘82: Eradication claimed ‘84: 1 ‘86: 1 ‘87: 44 ‘88: 53 ‘89: 241 Source: California Dept. of Food and Agriculture