Bitten by the Bug--Beetles, to Be Exact

Gil Challet has traveled to some of the most inhospitable places in the world in search of the wily diving beetle.

“Most of them are small and black,” said Challet, who has more than 7,000 diving beetles mounted, labeled and displayed in his Irvine home. He has collected them during excursions to Brazil, Peru, Colombia and South Africa, to name just a few diving beetle locales.

Challet is one of about 200 entomologists in the world who specializes in the study of the Dytiscidae family of diving beetles.

They’re not very attractive, admits Challet, 56, who is completing a second scientific paper on the beetles, which are from 1/25 to 3 inches in length.

“This one is black with gold spots on it,” he said, pointing to a specimen in the laboratory at the Orange County Vector Control District, where he has been district manager since 1974. “That’s probably the most colorful one.”

It is not an unusual avocation for a man who has made the detection and eradication of bugs and other pests--collectively referred to as vectors--his life’s work.

“I started collecting them when I was a university researcher. My job was to go around and get insects--beetles included--that would feed on mosquito larvae. I’d go out and collect these things, put them in large containers, introduce a certain number of mosquito larvae and see how many they ate. I would evaluate them as predators.”

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But at the Vector Control District, celebrating its 50th year in Orange County, Challet and staff breed mosquitofish, not diving beetles, to control the county’s mosquito population. The translucent, one-inch fish are stocked in flood-control channels, ponds, swimming pools--any body of water likely to breed mosquitoes.

“If we didn’t have mosquitofish, we would have to double our pesticide use and maybe even double our manpower. Once we plant mosquitofish, they take care of it. With pesticides, you have to go back every two weeks. A single mosquitofish can eat at least 100 larvae a day, probably more.”

The San Joaquin Freshwater Marsh near UC Irvine is the county’s largest breeding area for mosquitoes, Challet said.

“It is without a doubt the mosquito capital of Orange County. We can go down there and get 20,000 mosquitoes in a little trap overnight. We’ve tried almost everything in the book to control them.

“Most of our operations around the county are directed at the mosquito larvae in the water. But at San Joaquin Marsh, the vegetation is so dense, we can’t get the pesticide through the vegetation. So we have to go around at night when the adult mosquitoes are flying around and spray with fogging machines.”

Mosquitoes are carriers of the encephalitis virus, which is passed to the insect through the blood of small birds. An encephalitis outbreak in 1984 prompted the Vector Control District to begin trapping birds and testing their blood on a regular basis. The last significant increase in the virus among birds was about three years ago, Challet said.

The testing is part of an early warning system in which vector control’s 38 staff members routinely trap and test birds and rodents for signs of disease that could be passed on to humans.

The average 2,000 mosquito complaints a year placed to the Vector Control District pales in comparison to the county’s No. 1 vector problem: rats. Besieged residents place an average 10,000 calls a year to Challet and staff, appealing for help. Challet recommends poison in most cases.

“Rats are very suspicious of anything new in their environment. If you put a rat trap out there, you have to get them used to it. You should set the trap with the bait on it, unsprung. Leave it out there for three or four days for them to start feeding on it, and then on the fourth or fifth day you should set the trap.

“Mice, on the other hand, are very inquisitive. When I first moved into my house in Irvine, we had two mice and I put out two traps in the attic. I set them, I closed the attic door, I walked about 10 feet away and boom! I had both mice.”

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One threat that has yet to materialize in Orange County is the Africanized honeybee, Challet said.

“They are stalled out in Riverside and Imperial counties now. The experts think that they might have reached their ecological edge of the envelope. I still think they’re going to cross over the mountains and find a favorable habitat along the coast, but there are several things going on out in the deserts that we don’t quite understand.

“The environment in the desert is not really conducive to this bee; it’s more of a tropical bee. And there is a parasite on the bees that is killing them off. In most cases, the Africanized bees will take over a regular hive, but out in the desert we’re not seeing that. We don’t know what’s going on.”

Even if the so-called killer bees eventually reach Orange County, Challet said they are not as dangerous as some sensationalized stories would suggest.

“We feel that the media hype will really stir people up the first year. So we plan to have people who will go take care of the swarms that are in public places, and we will have public education materials in hand. But once people see that there’s not a group of bees knocking on their front door ready to sting them to death, I think they will get used to them.”

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Profile: Gil Challet

Age: 56

Hometown: San Diego

Residence: Irvine

Family: Wife, Linda, a second-grade teacher in Irvine; two grown daughters

Education: Bachelor’s degree in biology and a master’s degree in ecology from San Diego State University

Background: Two years research work on the biological control of mosquitoes at UC Riverside; entomologist at the Los Angeles County Department of Agriculture for two years; vector ecologist at Orange County Vector Control District since 1969, promoted to district manager in 1974

On tracking mosquitoes: “We have maps of all the known mosquito breeding sources in the county. Every street, gutter, catch basin that has ever bred mosquitoes--it’s all marked on a map. And we have a list of about 1,000 swimming pools that have at one time bred mosquitoes that we have to go back and look at on a routine basis.”

Source: Gil Challet; Researched by RUSS LOAR / For The Times