New York's bins are closing the lid. The rats will still have food

NEW YORK'S RAT problem is shrinking. Or at least the number of citizens complaining about rats is. Since the Department of Sanitation began requiring buildings and businesses to put their refuse in sealed containers, rather than leaving plastic bags on the sidewalk, 311 rat-complaint calls have fallen for 19 consecutive months. In 2024 they were down by more than 25% on the previous year, city officials say. In Hamilton Heights, a Manhattan neighbourhood that piloted the scheme first, sightings dropped by 68% in the first three months alone.

The policy has a simple logic. Rats are opportunistic omnivores whose range is constrained mainly by the distance to food: a typical brown rat nests within 100 feet of a reliable meal. Plastic bags, torn by wind, weather or the rats themselves, turn the city's curbs into a nightly buffet. Locking trash in a bin removes the buffet. "No garbage, no rats", as Dr Bobby Corrigan, a rodentologist who advises American cities, puts it.

To be sure, the programme is not yet universal. All businesses have been required to use containers since March 2024, and low-density residential buildings since later that year. About 1.1m official bins are now in use across the five boroughs, covering roughly 70% of the city's waste. The administration of Mayor Zohran Kwame Mamdani, successor to Eric Adams who first championed the policy, has pledged complete containerisation by 2031. The remaining gap - mostly large apartment blocks and co-ops - is being addressed with so-called Empire Bins, sealed on-street containers borrowed from European practice.

The decline in complaints is real enough. But 311 calls are a noisy measure. They depend on residents noticing rats and bothering to report them. As bins tidy the sidewalks, fewer people may look; as fewer people look, fewer calls come in even if the underlying population has not fallen by the same margin. The Department of Sanitation itself acknowledges that 311 data are "by no means a perfect" source. Sightings are a proxy for exposure, not a census.

The bigger complication is that the bins are addressing one driver of a problem with at least two more. In February 2025 a study published in Science Advances, led by Jonathan Richardson, an urban ecologist at the University of Richmond, used public rat-sighting data from 2007 to 2024 to show that warming cities saw their rat populations grow. New York City experienced the fourth-largest increase among the 16 cities examined. The mechanism is physiological: cold weather forces rats indoors and into shelter, limiting foraging and breeding. Milder winters and longer autumns extend their active season. Since the 1950s, New York's temperature has risen by about 0.3°C each decade, with further increases of between 2°C and nearly 5°C projected by the next decade, according to the city's own climate panel.

The bins cut off one food source. They do nothing about the other - or about the second force now working against the city. The containerisation programme is a reversal of a policy mistake made half a century ago. In 1971 the city council abandoned the secure metal cans that New Yorkers had used for generations in favour of plastic bags, which were lighter for sanitation workers to handle. The short-term savings in labour convenience created a long-term ecological subsidy. The current programme is unwinding that subsidy. That is the right move. But the arithmetic of warming means the city is now closing one tap while another is being turned on.

The cost of closing the tap is another structural question. The bins are not free. The common residential unit costs between $45 and $55. For building owners, the Centre for Building in North America and the Centre for Zero Waste Design estimate the average cost of waste handling at about $75 per apartment per month - more than the roughly $35 the city pays to collect and dispose of the waste, and a cost that flows, directly or indirectly, to residents. Co-ops and condominium owners fought the mandate on the grounds that it added an unaffordable operating expense. The city council overrode them in November 2025 by a vote of 30 to 11. The bins are a public health investment, in other words, but the bill is largely private.

A further confounding factor should not be ignored. Much of the early decline in rat sightings coincided with the dismantling of the city's outdoor dining sheds, which the city had installed during the pandemic and began removing in 2023. The sheds accumulated food waste and created sheltered nesting ground. Workers in Hell's Kitchen, where three corners at one intersection once hosted dining structures, say rats all but vanished when the sheds came down. The containerisation programme and the shed demolition are intertwined causes. The city has an incentive to claim credit for both.

What should happen next is not hard to see. The bins are the necessary first step, and they deserve credit for the improvement they have produced. But a city that wants to hold the line against rats must do more than lock away its rubbish. That means enforcing the container mandates - including the fines, up to $150, for non-compliance - rather than letting the programme stall under the weight of its own rollout delays, which have already provoked complaints from residents who asked for bins years ago. It means integrating rat management into climate adaptation planning, since a warming city is, ceteris paribus, a ratter city. And it means looking beyond waste management to the other structural attractants: the food-service industry, which generates a disproportionate share of accessible organic waste, and the building stock, which provides shelter in the form of gaps in curbs, foundations and subway infrastructure.

The deeper point is a familiar one for cities grappling with ecological problems of their own making. A single policy lever can produce measurable results. It cannot, by itself, reverse a trend that has more than one cause. New York is doing the right thing by putting its trash in bins. The question is whether it will do anything else before the next winter is too mild for the rats to stay away.