Rat teeth are almost as strong as steel. Rats were once pitted against dogs in fights in the back rooms of bars. Rats destroy food, spread disease, and have been known to bite people. Notorious gnawers, they are particularly attracted to wires. In his book “Rats,” Robert Sullivan says that rats cause up to 25 percent of all unsolved fire cases, 26 percent of electric-cable breaks, and 18 percent of phone cable disruptions.
Rats thrive on garbage in New York, which, according to the Department of Sanitation, collects 12,000 tons of refuse per day. There is no reliable census of rats, though some estimates for New York City have gone as high as 30 million, up from 250,000 at mid-century. The rat population across America is believed to be growing slightly faster than the human population.
The city relies on a multi-pronged effort to help fight the rats. “We hand-inspect vacant lots, hand out citations for garbage violations, educate people—and then there is extermination,” said Rick Simeone, director of the Department of Pest Control. Extermination is actually the least effective method, since rats are difficult to poison or trap and are such prolific breeders that exterminators cannot keep up.
Rats are far more neophobic than mice, meaning that they fear new things placed in their environment, so they avoid traps. Poisoning is the most effective way of killing them, but that is difficult as well: rats can detect poison in as small a quantity as two parts per million.
When extermination begins, rats simply accelerate their breeding. A single pair of rats can produce 15,000 offspring in a year, and they tend to breed until the have maxed out their food supply.
The only effective way to get rid of rats is to get rid of garbage. “In general rodents need food, water and a place to live,” said Celina De Leon, a representative of the city. “In the absence of garbage, leaks and harborage there is not likely to be an infestation.” Indeed, Montana did not have its first rats until 1923, because there were not enough people living there to support them.
If garbage were disposed of properly rats would run out of places to live. “Do not feed squirrels, pigeons and strays,” De Leon said. “If you do, you are feeding rats, too. Bag your garbage in plastic and put it in a can with a tight-fitting lid, and toss garbage in a trash can; not on the street, sidewalk or subway tracks.”
The Department of Pest Control is stepping up its education efforts, said Simeone. “We have all kinds of things going on,” he said. “It is pretty exciting right now. We have education and outreach programs and we have brought Bobby Corrigan in.” Robert Corrigan, a preeminent rat expert, is teaching a rat inspection and extermination course for the city. Recently, when a team of health inspectors gave a passing grade to a Greenwich Village Taco Bell—where video cameras later caught rats running around after hours—the inspectors were sent to Corrigan’s class.
The New York rat is the brown rat. The black rat once dominated the city but was driven out when the brown rat arrived, around 1775. The black rat was the vehicle of the plague because they live in attics and rafters, close to humans. The brown rat is a burrower. It lives in basements and sewers and is relatively shy. When a rat bites a person it is usually a sign of a bad infestation in the area. According to the American Journal of Epidemiology 514 New York City residents reported being bitten by rats between 1991 and 1994.
Rats are continuing to thrive in New York. Several private exterminators that were contacted were too busy to talk. A representative of Broadway Exterminating said that his employees were all working 12 hour days and still not getting all their work done. “There are just too many rats right now,” he said.