Eager to eradicate rats, New York City held its first National Urban Rat Summit, bringing together experts from across North America to share best practices in rodent control, including strategies borrowed from Europe.

For nearly 60 years, New York City officials have realized that killing rats alone won’t solve the problem. These creatures are remarkably prolific, with just one pair capable of producing up to 15,000 offspring a year. The city has tried various tactics, including attempting to curb the rat population with contraceptives, but the rodents have always found a way to thrive.

Now, the city is ready to try again, utilizing the latest advances in rodent birth control and better waste management.

New Pilot Project to Control New York’s Rats

A new bill introduced last Thursday could require the city’s health department to deploy salt-based sterilizing pellets in two neighborhoods as part of a pilot program. These pellets would target both male and female rats and would be used in so-called rat mitigation zones, covering at least 10 city blocks.

Shaun Abreu, a council member from Upper Manhattan and sponsor of the bill, predicts that this effort will be more successful than previous attempts, especially when combined with broader rat-control measures, such as using garbage bins and expanding composting programs.

One key benefit is that contraceptives are less likely to harm wildlife, unlike traditional poisons. This was seen in the case of Flaco, the beloved Eurasian owl whose death was partially blamed on rat poison.

City officials have adopted a comprehensive approach to combating rats. Loretta Mayer, the scientist behind ContraPest, a rat contraceptive, reports promising results from its use in the subway system. The bait contains active ingredients that impair ovarian function in female rats and disrupt sperm production in males.

Animal rights groups have also voiced support for the bill, arguing that contraceptives provide a more humane solution to rodent control, while also protecting animals higher up the food chain.

Mayor Eric Adams recently noted a decline in rat sightings since the city began using garbage containers, and this new project aims to combine both strategies to reduce the rat population as much as possible.

How New York City’s Rat Population Grew 800% and Infested the City in Less Than 65 Years

Rats first made headlines in New York City in 1860 when they reportedly mutilated and killed a newborn child. By 1865, The New York Times noted that the city had earned a reputation for having more rats “than any other city in the Union.”

In 1950, the city’s rat population was estimated at around 250,000. Since then, estimates have varied wildly, including a 1997 figure that claimed there were 28 million rats. However, a more conservative estimate from 2014 placed the number at about 2 million.

The early 1970s played a critical role in the surge of rats across the city. First, the federal government passed the Clean Air Act of 1970, leading New York City to ban apartment buildings from using incinerators to dispose of garbage.

Second, in 1971, the city introduced plastic garbage bags. Instead of metal trash cans, rats suddenly had easy access to an abundance of food, as more garbage accumulated that was no longer being burned.

Climate change was another factor. While rats don’t hibernate, their reproductive cycle slows down in winter due to the difficulty of finding food. As winters have grown warmer, rats have been able to reproduce more frequently.

From 1987 to 1996, New York City’s budget for rodent control dropped from $12 million to $5 million, leaving the city unable to maintain its three-pronged approach to pest management.

The rat problem worsened during the pandemic, with more garbage left outside for longer periods due to outdoor dining regulations and reduced garbage collection. Rats took advantage, multiplying in the streets.

According to the Department of Health’s Rat Academy, the only way to stop rats is to starve them. But in a city like New York, where streets are often lined with trash, that’s easier said than done.

This is why the city is seeking alternative methods. While there’s no plan to eradicate the rats entirely, the goal is to significantly reduce their population.