Rats first arrived on the scene in the late Miocene era, 10 to 15 million years before Homo sapiens. Today, there are at least 370 species of rat. The types that have plagued humanity — the black and the brown — originated in Asia. Precisely how and when these rodents migrated to the Western world is unknown, but they probably hitched a ride with unwitting merchants around the turn of the first millennium. The Norway Brown has called Boston home since the 18th century, when it came over on British merchant ships and literally ran its smaller cousin — the black, or "roof" rat — out of town. Ever since, despite our best efforts, Norway Browns continue to survive, and even thrive, in our company.
"They’ve been under such great pressure over the centuries, and yet they endure," says Colvin. "If you watch their behavior, they are really great at risk management. Their adaptive traits for survival — that is to be marveled at. From a standpoint of public health, they are terrible. But from an ecological perspective, they are wonderful, fascinating critters."
Indeed, rats are impressive physical specimens, equally adept at climbing, swimming, and burrowing. Because it has a collapsible skeleton, a full-grown rat can fit through a hole the size of a quarter. Rats can walk high wires and leap two feet into the air. They can gnaw through steel and concrete. But it’s in the sexual arena that rats really start to shine. A female rat reaches sexual maturity at a few months old, after which she averages 22 sex acts a day. She can give birth to a litter of pups every three weeks, with six to 12 pups in a litter, and can get pregnant 48 hours after giving birth. As Robert Hendrickson writes in More Cunning Than Man, "A single pair of rats can potentially produce 359 million heirs in three years."
Rats are also impressively savvy and resourceful creatures. Hendrickson relates a chilling instance where rats took to "farming" crabs, taking the live animals into their burrows, biting off their legs to render them harmless, and then harvesting them at their leisure. "Countless laboratory tests," Hendrickson writes, "have shown that the rat is an extremely intelligent animal blessed with a good memory, excellent insight, and the ability to solve problems." Dominant rats, for example, will often use subordinates to scout out a potentially dangerous environment, or as "tasters" to test suspicious items of food.
Like humans, rats have extremely complex social relationships. And, like many humans, they have a taste for beer. One study — in which rats ignored levers that provided slow and steady supplies of food in favor of levers that doled out larger helpings intermittently — suggests that rats may even have a penchant for gambling. There have also been studies suggesting that if you treat a young rat kindly, it will develop into a smarter and more affectionate — a more well-rounded — adult. This fact has not been lost on a growing number of American pet owners who shun the dog, the cat, and the parrot in favor of the rat (see "Rats Amore," sidebar).
Even those who don’t call themselves rat fans admit to having some degree of sympathy for the animal. I myself recall seeing a rat being chased across the plaza of the Christian Science Center, then stomped, one afternoon a few years ago. The animal’s terrified squeals, which intensified every time its assailant brought his boot down on its back, filled me with pity. Rats are living creatures too, are they not?
Carl the homeless guy, for one, admits to harboring a trace of sympathy for the animals. "You can’t blame the rats," he says. "They’re just trying to survive."
Such arguments are unlikely to sway John Meaney, who calls rats "the enemy" and refers to areas with high concentrations of the animals as "hostile ground." Meaney would gladly see the city’s rat population utterly and mercilessly decimated — a prospect growing increasingly dim in a winter so warm the rats are shagging openly in the streets. But Meaney continues to be hopeful. "This year we’ll increase our control measures, start early," he says. "We’ll keep it under control."
When reminded that such mild weather will almost certainly lead to a booming rat population in the spring, Meaney responds with a terse, "Not in this city." Even he, though, admits that until the city’s trash situation is brought under control, the rat problem will never be licked. "There’s still room for improvement," he says. "You just kill as many as you can."
Peter Catalano, who’s on the steering committee of the Fenway Action Committee, takes a less charitable view of the city’s ongoing trash woes. "The fundamental problem is that the Menino administration allows dumpsters to overflow and allows trash to be left out overnight," he says. "They want to have conventions in this city, and they can’t pick up the trash in the Back Bay. You see these mountains of stinky trash, and that creates a feast for the rats. I think compared to most other towns, Boston is an absolute laughingstock and a disgrace. They’re courting all these big conventions — it’s a joke. We’ll see if the delegates like Boston’s wildlife rustling across their feet."
The Central Artery’s Fothergill, meanwhile, laments the fact that the nearly $2 million poured into his department over the last decade is starting to dry up. "With the budget cuts, all of our research went by the wayside," he says. "One time, we had all these grandiose plans to map the entire area. I used to enter every code-enforcement ticket, I did mapping of all the sewers. But all that support is gone. We’re pretty much battling the rats from the outside now."
On a balmy winter morning, Fothergill spends a half-hour marking the entrances to the burrows that have appeared alongside Boston’s Holocaust memorial. The memorial has proven to be a big hit with local rats — not only is there an abundant food supply at nearby Haymarket, the steam that billows from the memorial’s glass chimneys keeps the rats warm and snug. So Fothergill will kill off the rats that have set up shop here. Next month, he will kill some more. The month after that, he will kill more.
But the rats will come back. Given the right conditions, they always do.
At the height of the Artery project’s anti-rodent efforts, some experts were predicting that the city could find itself completely rat-free by 2005. Fothergill, when asked about these predictions, lets out a bitter laugh. "Oh, no," he says. "No, no, no, no, no."
Chris Wright can be reached at email@example.com