Rats chew car wires, enter homes in Berkeley Hills, causing costly damage

Rats are proving an often expensive nuisance in some parts of Berkeley. Photo: Wikimedia Commons

By Steve Taylor

The Berkeley Hills boast stunning natural beauty, high education levels, big incomes and robust property values. But like a debutante with an STD, the neighborhood also has an embarrassing secret: a recent upsurge in reported rat activity.

The pests are nesting on car engines, where they sharpen their teeth by chewing on wires, which leads to major repair costs. Worse, Roof Rats are invading attics and Norway Rats are moving into basements and crawl spaces, pushing exterminator bills to thousands of dollars.

“Based on [the] number of calls to my office and posts on Nextdoor.com, I think it’s safe to say that North Berkeley has a rat infestation problem,” wrote City Councilwoman Susan Wengraf in her newsletter in November.


“We’ve lived here on Avenida for 50 years,” one hills homeowner said. “There is a dramatic increase in the arrivals of rats. Alameda County identified a serious infestation two years ago. … We had a hole we didn’t know about and it will cost us $7,000 to clean, remove and re-sterilize our attic and some crawl spaces.”

The homeowner cautions DIYers not to clean up rat droppings without wearing a mask and waterproof gloves. The vermin can be vectors for diseases such as salmonellosis, leptospirosis, murine typhus, even the plague, although the plague is clearly not as common in urban areas now as it was the Middle Ages.

At Berkeley’s Environmental Health Division, Manager Manuel Ramirez takes a measured approach when asked if rat problems are growing in the hills. “I haven’t noticed an increase in complaints,” he said, “but rodent infestation is always an issue in a city environment. They’re here for a reason: we’re providing them with shelter and food.”

The hills’ ample foliage harbors them, and residents overfeeding of wild birds and pets can guarantee a steady meal plan for nocturnal scavengers. In addition, construction activity can drive pests from their preferred habitats into our cars and homes, Ramirez said.

This reporter and Berkeley Hills resident has his own experiences with the rodents. Rats tried to nest on the engines of my cars last summer. They seemed bent on preparing nests for winter. I baited snap traps with peanut butter (it’s what the pros use) and placed the traps in the engine compartments. Then I propped the hoods open about 1.5 ft. using wood poles so the engine compartments weren’t so protected and inviting to the shy creatures.

Rats are wily. I learned that trapping them requires persistence: keeping the traps ready even if the prey gets away a few times. Eventually, I caught a couple of rats and the problem ended, no wires chewed.

Others report far worse car-rat encounters. “Two days apart our two cars (one old, one new) wouldn’t start and had to be towed,” said Monika Eisenbud two days before Christmas. “Rats had chewed wiring in both, with the wiring harness needing replacement in both cars (pricey!). This has never happened to us before in 20 years of living in the Berkeley Hills.”


Adds another neighbor: “I had extensive rat damage on my Range Rover a few years ago where they chewed through the engine wires and casing and caused about $7,000 in damage. It took the shop about a month to repair. When it’s super cold, rats like to hide in warm places … We solved the issue by having a pest-control person put traps around the car.”

The city offers extensive advice on rodent-proofing homes.

What else can be done? Some residents recommend getting a pet cat, or – better yet – befriending a fierce feral one.

Kristen Van Dam, who lives near Tilden Park, recommends owl power: “I am (among other things) a site assessor for the Hungry Owl Project,” she says. “Barn owls are by far the most prolific consumers of rodents out of all our local owls. And, unlike cats, they don’t prey on native songbirds. If there are a few neighbors interested in setting up a barn owl box, I’d be happy to provide expertise and advice.”