Nanaki Singh was walking home last week, hours after the remnants of Hurricane Ida turned many intersections in the Brooklyn neighborhood of East Williamsburg into knee-deep ponds, when he noticed a dead rat lying smack in the middle of the sidewalk. And another. And then another.
“I saw a total of six dead rodents within 10 square feet,” Mr. Singh, 23, said in a Twitter message to The New York Times on Thursday. He posted photos of the evidence on the social media site, along with some somber commentary and an “R.I.P.”
He was not the only one to notice that the storm had left a segment of the city’s rat population — which has never officially been counted, although estimates range into the millions — distressed, displaced or deceased.
On the shorelines of Jamaica Bay in Queens and Brooklyn, walkers spotted an unusual number of dead rats on beaches, as first reported by Gothamist. On the Upper East Side, one resident saw not one but three live rats skitter into her building, one stepping on her foot along the way.
Scientists who study urban rats said that the surge of water that coursed through streets, pipes and basements last week likely drowned thousands of rats and disrupted the habitats and feeding habits of many more.
“Just like people were caught off guard by the swell of flooding water coming down the streets, it’s possible that some of these rats also couldn’t get away in time,” said Jason Munshi-South, a professor of biology at Fordham University.
More rats live in sewers than in the subway, mainly in the older pipes that are made of brick; rats even nibble out mortar and burrow into the crevices. The pipes usually contain some air, and rats are relatively good swimmers, Dr. Munshi-South said — but with storm water so overwhelming the system that water gushed like geysers out of toilets and manholes, many could have been swept under by pressure or lacked enough space to take a breath.
But the rat population will more than survive this latest disruption, as it has many others. Early in the coronavirus pandemic last year, when restaurant closures reduced the availability of tasty scraps, the rodents improvised by finding edible pickings in residential garbage, which increased with the suspension of compost programs.
And in any case, scientists say, rats reproduce quickly and recoup any dip in population within months.
“From what I saw this summer,” Dr. Munshi-South said, “the rat population is quite healthy.”