Uptown Rats : Vegetarian rodents that prefer the suburbs have settled in some of Orange County’s nicest locations. It’s the Vector Control District’s job to make them feel unwelcome.

Rats? In squeaky-clean Orange County? The four-legged kind? Yes, about 2 1/2 million of them, about one per person.

They’re not your grimy New York alley rats. This variety, the roof rat, is better suited to the Orange County lifestyle. That is, it’s slimmer, more active, hardly ever eats meat and prefers the best neighborhoods.

Last year, the area to complain most about rat infestation was in well-manicured Laguna Niguel--nearly two complaints a day. Neighborhoods in San Juan Capistrano were runners-up, and high-rent districts such as the Fullerton hills and Corona del Mar were well represented.

It’s the lush landscaping that’s so attractive to the rats, says Fred Beams, assistant manager of the Orange County Vector Control District. Besides shelter, the ivy, fruit trees and snails provide a rat banquet.

“You walk up to a $3.5-million house in Fullerton and tell them they have a rat problem, and they refuse to believe it,” Beams says.

But believe it and do something about it, he urges, because it’s taken a lot of work to keep the rat population down to merely a couple million. Ease up and the population could easily double.

Now that summerish weather is here, rat sightings will increase, Beams says. “As the weather warms, people spend more time on the patio, and they’ll look up and see a rat coming down the telephone wire. It may be their first sighting.”

Some people are horrified just by the sight of rats. “I don’t much like to be around them myself,” says Beams, a 32-year veteran of the district.

Others are infuriated to discover rats have gnawed their appliance hoses and automobile wiring. (Rats’ front teeth never stop growing, so they gnaw to grind them back.)

But the real reason to control rats is disease, Beams said. A rat can be a flea-mobile, and rat fleas can drink up plague bacteria from one mammal and inject them into others.

That’s bubonic plague, as in the Black Death, the five-year pandemic that killed as much as a third of Europe’s population in the mid-14th Century. It’s still around, still nasty and now and then someone contracts it.

Orange County’s modern disease records, which extend back to 1928, show no cases of plague, but in other parts of the Los Angeles Basin, there have been four confirmed cases in the last 14 years. A man in nearby Diamond Bar contracted the disease in 1979.

All survived, since modern antibiotics can cure plague if used in the early stages.

Right now, the county’s rat situation is stable, Beams says. Rats trapped and tested show that only one in 10 has even one flea. And the rats themselves are not diseased, he says. The real reservoirs of plague bacteria are ground squirrels.

But as they have done before, rats could become the bridge that brings plague into human contact.

Why aren’t the neighborhood cats helping out? “When you’re getting fed for nothing, why take on a foot-long rat?” Beams asks.

So it falls to the district’s 16 technicians to carry on the rodent war.

Al Arballo, one of the district’s technicians, works the Mission Viejo area. Driving to the next call, he nods toward the densely landscaped slopes on either side of Los Alisos Boulevard.

“Look at this. Rats are going to live in this stuff, and how often does anyone come to trim it back? They live well here. It’s a clean area, lots of food--pet food, snails, berries--and they don’t require that much water. They can get enough off a sprinkler head.”

On the other hand, the Norway rat, the rat of Eastern and Midwestern cities, must find a good water source every day or two. It’s only one of the differences.

The Norway rat (which probably comes from China, not Norway) is the stouter, with smaller eyes and ears, a shorter tail and a blunt nose. The roof rat has a sharp nose and a tail longer than its body.

The Norway rat likes a high-protein diet and often finds it in the trash. The roof rat is less likely to be in the dumpster. It’s almost a vegetarian, shinnying up trees to eat the fruit and nibbling on ivy shoots.

Both rats are very intelligent, but while the Norway rat can become a good pet, the more skittish roof rat resists domestication.

There are few Norway rats in the Western states. “There’s a fair population in downtown Los Angeles. That’s about it,” Beams says. Roof rats will live in the city, “but they’re really the suburban rat,” says Beams. “Some people call them the commuter rat. Actually, they will travel a fair distance for food.

“We did some studies in Orange. We put little transmitters around their necks for about three weeks. We found out that while they’re nocturnal, they are sometimes active in the daytime.”

Some take to freeway landscaping and never leave, Beams says. Others live in the chambers formed by the dead, drooping fronds of palm trees. “They can nest there, and they’re away from predators.”

Dense bougainvillea vines are also popular with rats, but by far their favorite home is Algerian ivy, the kind with the large leaves. “And it’s terrible to get rid of,” says Beams. “If I were a homeowner, I just wouldn’t plant ivy, period.”

Occasionally, the roof rat emerges and is seen. A cocktail lounge in Orange is supposed to have had a rat amble across its bar about the same time each night, “and the regulars kind of adopted it,” Beams says. “Until the health department heard about it.”

More often, the sight of a rat results in a call to the vector control district, which gets 6,000 or more a year. A technician shows up to inspect, advise and set out rat poison free of charge. But only outside in the yard. Indoor work is left to commercial pest control companies.

“Fifty percent of the calls are people having problems indoors,” Arballo says. “They hear them in the walls, maybe find droppings in the garage.”

Garages are a particularly common haven, for even if garage doors are closed, a rat can get through a half-inch gap at the floor. “Half an inch is plenty of space. If they can get their head through, the rest of the body can make it. They can flatten out to nothing.”

The householder’s reaction to the discovery can vary from one extreme to the other, Arballo says. “One lady, she’s literally crying. Another, it’s a big joke. I get people who don’t want me to tell the neighbors.”

It’s a little silly, he says. “Good neighborhood, bad neighborhood, the rats are there either way.”

That rats are attracted only to decaying neighborhoods is just one of the myths, Beams says. Another is that rats appear in new neighborhoods because they’re on the outskirts where rats live naturally.

“There are native rodents, and new places like Rancho Santa Margarita have trouble with them at first. But they are not rats,” Beams says. “The rats show up 10 or 12 years later like clockwork. We don’t know how to prevent it. They probably walk there. They migrate from one grove to another, and a few probably hitchhike in trucks.

“We try to convince homeowners to take action. We’ll put out the poison, but we expect them to follow our advice. But there are no strong laws that compel them to do it.”

Rats, by ZIP Code

Complaints of rats made to the Orange County Vector Control District in 1991.

ZIP Code, Location: Reports 90620 Buena Park: 73 90621 Buena Park: 48 90623 La Palma: 16 90630 Cypress: 46 90631 La Habra 7 90680 Stanton: 18 90720 Los Alamitos: 91 90740 Seal Beach: 18 90742 Sunset Beach: 1 92615 Huntington Beach: 1 92621 Brea: 75 92624 Capistrano Beach: 26 92625 Corona del Mar: 97 92626 Costa Mesa: 164 92627 Costa Mesa: 86 92628 Costa Mesa: 1 92629 Dana Point: 59 92630 El Toro: 131 92631 Fullerton: 75 92632 Fullerton: 58 92633 Fullerton: 79 92634 Fullerton: 2 92635 Fullerton: 100 92640 Garden Grove: 128 92641 Garden Grove: 103 92642 Garden Grove: 3 92643 Garden Grove: 42 92644 Garden Grove: 33 92645 Garden Grove: 49 92646 Huntington Beach: 165 92647 Huntington Beach: 151 92648 Huntington Beach: 23 92649 Huntington Beach: 46 92651 Laguna Beach: 152 92652 Laguna Beach: 1 92653 Laguna Hills: 91 92655 Midway City: 25 92656 Laguna Beach: 49 92660 Newport Beach: 128 92661 Balboa: 3 92662 Balboa Island: 1 92663 Newport Beach: 12 92665 Olive: 41 92666 Orange: 28 92667 Orange: 175 92668 Orange: 16 92669 El Modena: 77 92670 Placentia: 78 92672 San Clemente: 96 92675 San Juan Capistrano: 72 92676 Silverado Canyon: 2 92677 Laguna Niguel: 530 92678 Trabuco Canyon: 1 92679 Trabuco Canyon: 28 92680 Tustin: 164 92681 Tustin: 1 92683 Westminster: 160 92686 Yorba Linda: 124 92687 Yorba Linda: 45 92688 R. Santa Margarita: 7 92690 San Juan Capistrano: 2 92691 San Juan Capistrano: 266 92692 San Juan Capistrano: 382 92701 Santa Ana: 87 92702 Santa Ana: 3 92703 Santa Ana: 34 92704 Santa Ana: 63 92705 North Tustin: 175 92706 Santa Ana: 93 92707 Santa Ana: 62 92708 Fountain Valley: 234 92709 El Toro Marine base: 1 92713 Santa Ana: 1 92714 Irvine: 54 92715 Irvine: 74 92720 Irvine: 15 92801 Anaheim: 56 92802 Anaheim: 85 92804 Anaheim: 113 92805 Anaheim: 60 92806 Anaheim: 75 92807 Anaheim Hills: 128 92808 Anaheim Hills: 10 Total: 6,195

Favorite Haunts ZIP Code, Location: Reports 92677 Laguna Niguel: 530 92692 San Juan Capistrano: 382 92691 San Juan Capistrano: 266 92708 Fountain Valley: 234 92667 Orange: 175 92705 North Tustin: 175 Source: Orange County Vector Control District