gross things

Researchers Conducted a Rat Census in New York City

In this June 15, 2010 file photo, a rat moves along the ground near the subway tracks at Union Square in New York.
Photo: Frank Franklin II/Corbis

Rats: They are disgusting and they are everywhere, especially if you live in a large city like New York. It’s hard to wait for the subway here without seeing one scurrying across the tracks, presumably in search of diseases to intentionally infect itself with and pass on to humans. But do rats, as many have claimed, actually outnumber humans in the Big Rat-ple (sorry)? Not so, claims a new study in Significance from researchers who, yes, attempted a rat-census.

To the press release:

The analysis classified rat sightings by city lot, of which there are roughly 842,000 in New York City. The researchers estimated 40,500 rat-inhabited lots in the city. By liberally assuming that 40 to 50 rats belong to a typical colony and that one full colony occupies each rat-inhabited lot, the researchers concluded that 2 million would be an extremely generous estimate of the city’s rat population.

While the rat population remains a serious problem in New York City, there appears to be no evidence supporting the 8 million number. In problems like this, the city’s open data is invaluable for challenging rumors, evaluating community need and establishing government efficacy,” said Jonathan Auerbach, author of the Significance study winner of the YSS/Significance Young Statisticians Writing Competition.

So rest easy, New Yorkers: There are a mere 2 million or so disease-ridden tick-trains scurrying about at your feet at this very moment. Plus all those mice. And roaches. And weird weasel-like creatures. It’s a helluva town!

Researchers Conducted an NYC Rat Census