When weather is drier, the rats seem to love living under the soil, and can dig deeper than water can seep. They could even have been safe in their burrows as the storm swept the city Monday. But many likely were out on the hunt for food.
"They're in the subway, in spite of the subway," said exterminator Benett Pearlman of New York-based Positive Pest Management Corp. The underground systems are the first things rats reach when breaking through the soil in search of sustenance. This perpetual hunger likely killed many as floodwaters washed back through their tunnels into their nests, probably killing the sick, the elderly, and new mothers with their young.
The many thousands that made it out alive—most using the same stairways people use, Pearlman said—were trapped aboveground on Tuesday, hunkering down behind trash bins and under cars until nightfall.
Sandy has brought a feast to their feet. New sources of food are washing out of the waterways and along flooded streets, including loads of rotting trash, other rats, pigeons, and fish. The well-fed rats will burrow beneath buildings under cover of night to establish new homes, sliding into holes as small as a half inch (1.3 centimeters)—the width of their skulls—even though their bodies can measure up to 18 inches (46 centimeters) long.
As for New York's other ubiquitous wildlife, Tufts University animal behaviorist Robert Cook thinks pigeons are in an excellent position when the city is flooded and windy. They're originally cliff-dwelling birds, so skyscrapers suit them, Cook said. They'll find a safe place to get out of the wind, then fly to new food sources.
"There's a reason rats and pigeons are so successful around humans," he says, "They're well adapted to what we do."