For nearly 60 years, New York City leaders have understood that they could not kill their way out of the rat problem.
Rats are prodigious breeders, with one pair having the potential to produce 15,000 descendants in a year. City officials have tried repeatedly to give them contraceptives and diminish their ranks, but the rats have prevailed.
Now, citing advancements in rodent birth control and trash storage, the City Council wants to try again.
A new bill being introduced on Thursday would require the city’s health department to deploy salty pellets that sterilize both male and female rats as part of a pilot program. It would take place in two neighborhoods within so-called rat mitigation zones covering at least 10 city blocks.
The bill’s sponsor, Shaun Abreu, a council member from northern Manhattan, said that this attempt would be more effective than past efforts, particularly when paired with the city’s broader push to fight rats, which involves putting trash in containers and expanding composting.
“We believe that we need to take a shock-and-awe approach to the rat problem by throwing everything we have at it,” he said.
There is another potential benefit: Contraceptives are not likely to harm wildlife like Flaco, the beloved Eurasian eagle-owl whose death was blamed in part on rat poison.
“Birds of prey shouldn’t have to eat rats that have rodenticide,” said Mr. Abreu.
The major question is whether the city can finally get rat birth control right.
“Will we ever eradicate rats? I don’t think so,” he said. “But you should do everything you can to reduce the size of the population.”
Mayor Eric Adams has made fighting rats a signature initiative. He installed his own rat czar, Kathleen Corradi, and started an ambitious plan to move trash from fetid garbage bags off the street and into European-style containers.
Mr. Abreu has been working with Loretta Mayer, a scientist who created ContraPest, a rat contraceptive that transit officials said had showed promising results when used in the subway. The bait contains active compounds that target ovarian function in female rats and lead to infertility in male rats by disrupting sperm cell production.
Dr. Mayer, who now runs a nonprofit dedicated to humane animal population control, said in an interview that the pellets were full of fat and salt and they were so delicious that rats preferred them to digging through the trash.
“It’s better than pizza,” she said.
Dr. Mayer said the greatest challenge would be scaling up to have enough pellets to distribute the contraceptives more broadly. She said the cost was low, at about $5 a pound.
Other cities have tried rat contraceptives, including Boston, Columbus, Ohio, and Hartford, Conn. Mr. Abreu said that past attempts in New York City had been unsuccessful because officials were not persistent enough. Or they used liquid bait instead of pellets, he said, and did not pair it with trash containerization, which gives rats fewer culinary alternatives.
Mr. Abreu has become an evangelist for the mayor’s “trash revolution,” and his district is where the city’s trash containerization pilot is taking place.
Some animal welfare groups support his bill, arguing that contraceptives are a more humane way of dealing with rats and will help other animals higher in the food chain.
Flaco the owl captured the city’s imagination after he escaped from the Central Park Zoo, and his death in February after a year of freedom was met with an outpouring of grief. He died after apparently striking an Upper West Side building, but a necropsy found that he had a life-threatening amount of rat poison and pigeon virus in his system.
“Honestly, it took the death of Flaco for people to really pay attention to this issue and the fact that his tragic death could have been avoided,” said Kathy Nizzari, the chair of the Lights Out Coalition, a group dedicated to protecting wildlife. “Why is the government spending millions of dollars on poison when it doesn’t even work?”
