Of the many myths that have followed the Brown Rat around New York City down the years perhaps the most commonly cited –and loved– is the one about there being one rat per person. That would equal more than 8 million Norway Rats, as they are also called.
How many rats there are in New York City, however, is anyone’s guess. As a health department spokesperson recently noted, you can’t easily tag and follow wild Norway Rats—life-threatening disease in tow and all.
Whether called Norway, Brown, wharf, gray, sewer, barn or house rat, it's the same species (Rattus norvegicus) that arrived in the Big Apple in the late 1700s, eventually pushed out the Black Rat and has dominated urban centers in the country for generations since.
Rat inspections have increased citywide in recent years, increasing by 18 percent last year to 128,900, DOHMH reports. In Brooklyn, the number of inspections increased by 9,000 to 41,000 from 2010 to 2012. The department issued 1,483 rodent violations to residential and commercial property owners in 2012, down by more than 300 from 2010. Since the storm the city has handed close to 2,000 violation notices for rat activity.
Though news reports and interviews with exterminators suggest an increase, even a surge, in the rat population in Brooklyn after Hurricane Sandy, data from the New York City Department of Health and Mental Hygiene suggest otherwise.
Extensive inspections in flood zones after the hurricane did not see an increase in the rat population, says DOHMH spokeswoman Diane Hepps. In fact, rat complaints to 311 were lower after the storm than in the previous year—often the case, she says, as large storms can flush rats into the open, but might also drown them.
But some Brooklyn residents say rats were a persistent or even growing concern before the storm, and from experts and community boards there have been calls for a more comprehensive strategy to get rid of Brooklyn's rodents.
Associated with neighborhood transition
As if Norway Rats are the underground gastronomes of gentrification, up-and-coming neighborhoods overflowing with garbage from newly minted bars and restaurants turn up the highest numbers in the borough, according to people who kill rats for a living.
Exterminators cite Williamsburg, Bushwick, Bedford-Stuyvesant and Brooklyn Heights as problem areas, and city statistics offer circumstantial evidence to back their claims up.
The city's rat information portal (RIP) indicates that neighborhoods that have yet to see significant gentrification also see fewer rats. Brownsville, one of the poorest areas in the borough, saw the highest number of initial rat inspections for the borough, almost 4,000 through 2011. Yet, remarkably, less than 2 percent turned up any signs of rat activity. Crown Heights also received more than the average number of inspections in 2011 according to the latest data, yet of the near 1,700 visits, only 7 percent found active rat signs.
However, half of almost 700 inspections performed in neighboring (and hipper) Bedford-Stuyvesant turned up signs of rat activity. Sixty percent of 105 inspections performed in Brooklyn Heights suggested rat activity. And half of over 500 inspections in East Williamsburg also pointed to rat activity, over the same period.
Areas as far apart as Stuyvesant Heights and Greenpoint in North and Central Brooklyn also bore marks of active rat signs.
Brooklyn's most controversial development site at Atlantic Yards figured into news reports about rat sightings. One resident on Dean Street says that as ground broke on the project in 2010, rats flooded the neighborhood, presumably from on-site burrows. One store owner blocks from the stadium describes seeing a dozen or so of the nocturnal creatures scatter as he went to his car one morning in the wee hours. Residents reported seeing rats as big as cats and claimed that, for a year during construction, backyards by Dean Street, adjacent to the Center, were uninhabitable.
One local tells City Limits there appears to have been a letup in rat activity since the center opened last September, but adds that the summer of 2012 was frightening. He looks forward anxiously, he says, as temperatures rise. Since cold winters curb population growth for the warm-blooded creatures, coming spring and summer months could portend more problems.
King Rats? Yes. Giant Rats? Maybe.
Even without an accurate estimate of their number in the city, we still know a lot about rat behavior and extermination, through decades of research.
Rats live in nested colonies many feet underground that are organized hierarchically. Colonies are dominated by the largest male, the notoriously promiscuous King Rat—usually the fattest one, who marks his territory by maiming others. A rat found with part of his tail bitten off is marked for lowly status. Once the colonies are disturbed, rats will exit through a “bolt hole” in the burrow system and seek shelter elsewhere.
Stories of gigantic rats are often discounted by experts as mere mythologizing. Although mature Norway Rats at two months old can span more than 18 inches, they rarely weigh more than a pound. The average weight in a city is closer to half that. The Norway Rat’s ability to raise its fur catlike when threatened usually explains the reports of enormous rodents.
But size isn't everything: A female rat in the wild is mightily fecund. Under ideal conditions she may produce between 25 and 35 pups or more in a year, if she lives that long (most rats in the wild don’t make it past six months). Less than two days after her 22-day gestation period, she is ready to start the cycle again.
However, fertile as she is, she can’t breed if she can’t feed. And that's the key to stopping rats.
Lessons from the 'Big Dig'
Much of what is known about rats can be credited to mammalian biologist Dr. Bruce Colvin. Colvin says if we implemented all that we know about rats we could dramatically reduce their numbers in New York, where they are accused of causing everything from debilitating illness to house fires due to their incorrigible tendency to gnaw.
Colvin was mentored by the greats in the modern field of rat ecology, including its father, David E. Davis, debunker of the myth about one rat per person in the Big Apple. (He put the true figure at 250,000 in 1949.) Colvin developed an "integrated systems approach" to killing the pest, novel for the time and now the model for urban rat control.
It was initially deployed during the Big Dig project in Boston almost 20 years ago. Colvin and his team of handpicked biologists spent 10 years targeting rats along a route of seven miles for the federally funded project. When it was completed, almost 97 percent of the rat population had been eliminated. He credits its success to cooperation between government, business and the community, and a paradigmatic shift in thinking that put the focus of extermination efforts on the rats' environment.
The approach, he says, is simple. Fill in cracks in sewers and sidewalks, for example, and rats have nowhere to nest. Cut them off from their food supply and their numbers might fall so dramatically, you might not see rats at all.
Trashing garbage bags
The Bloomberg administration points to a similar program, its Bronx "rat indexing" initiative, as an instance of aggressive action against rodents. In the pilot, which began in 2007, inspectors walked every block of a 12-square-mile area that suffered intense rat problems, looking for signs of infestation and, on finding evidence of rats, ordering owners to address the problem. According to the city, the project reduced the number of properties with rodents by 83 percent; it's now being extended to Manhattan.
But Colvin believes a broader focus on the way New York disposes of refuse is in order. The rats' ally, says Colvin, is the common plastic garbage bag. Left at the curbside, it's a buffet for vermin. If New York replaced the plastic garbage bag with the more realistic metal or hard-plastic receptacles, the five boroughs would see a lot fewer rodents, Colvin says.
Even in rat hotspots in Brooklyn, a mix of trash-disposal methods is visible. Though Forest Ratner has handed out hundreds of trash receptacles since construction began, plastic refuse bags a plenty can be seen on the streets surrounding the Barclays Center
Despite the increased number of inspections, since 2009, the city's budget for pest control has been reduced by 16 percent and the number of staff cut by a third—although the remaining staff is now more evenly distributed between a central office and borough divisions.
According to 311 statistics, the city recorded 239 rat sightings in Brooklyn in January, up from 225 in January 2012 and 162 in January 2011.
The city's annual register of community board budget requests reflects broad concerns about rodents. A proposal from Brooklyn Community Board 1 to improve refuse collection for eight public housing developments affecting 11,000 units that experience “chronically inadequate refuse collections” was denied. Board 2, which contains the Atlantic Yards project, also requested extra funds to address the escalation in rodents due to large-scale construction in recent years, but was turned down because "DOHMH did not find signs of rats in Atlantic Yards."
Resilient, skillful enemies
Around the Barclays Center, black boxes known as “bait stations” are also in view, sometimes on the same sidewalk as the plastic trash bags.
However, the value of rat traps on their own is doubtful, says exterminator Jim O'Brien, because rats have whisker-like hair that helps them avoid new things in their path. Rats are notoriously neo-phobic, according to rat expert and entomologist Dr. Jill Gordon.
Rat poison—usually an anti-coagulant that kills by causing internal bleeding--can also be merely a stop-gap measure, Colvin says, bringing short-term relief but unlikely to stem the tide of rats in the long-term.
Rats can jump three feet vertically and four horizontally, dig three feet down, survive a 50-foot fall, swim a half-mile, squeeze through a half-inch opening and chew through aluminum sheeting or cinder block. Though rats suffer from poor eyesight and are chiefly nocturnal, they have a remarkable sense of smell and are capable of picking up ultrasound.
Given those skills, relatively warm but moist weather, plenty of food and a safe place to nest, a colony can take off in no time.
Rats are, however, timid creatures, according to Gordon. That rats are violent is another myth, she says. Contrary to popular belief, they will run rather than fight—unless they are cornered, when they are capable of ripping flesh open with their incisors. Because of the mammals' timidity, rat bites are uncommon in the city.
But it is rats' capacity to spread dreadful diseases and destroy food that causes greatest concern among experts and exterminators. The Norway Rat’s fur and feet (in addition to its bite) spread a variety of dangerous pathogens, including leptospirosis, also known as Weil’s disease, a bacteria that can lead to kidney damage—meningitis, respiratory distress and even death. Norway rats are also linked to hemorrhagic fever and rat-bite fever. Ticks carried by rats can cause typhus.
Salmonella, a bacteria dreaded by restaurateurs, can be spread by eating or drinking food or water contaminated by rat feces.
Indeed, it all comes back to food. Rats eat large amounts of it, and they contaminate even more with their urine, feces, and hair. At least 20 percent of the world's food is eaten or contaminated by rats and mice each year. Some of it comes in plastic garbage bags.