New York is intensifying the fight against the rodent population on the city streets – targeted measures are being taken to destroy them, inspection control is being strengthened, and new methods of storing garbage are being introduced. However, research shows that mice have developed resistance to common household poisons, and rats have learned to avoid traps. Read about how effective the measures taken to curb the growth of the rodent population in New York are and what new methods can help in the fight against rats that have already adapted to standard methods of rodent control.
Researchers from Rutgers University (New Jersey) analyzed the DNA of 300 mice and gray rats captured in densely populated areas of New Jersey, Pennsylvania, Washington and New York. The results showed that about 70% of mice have genetic mutations associated with resistance to rodenticides widely used to kill them.
According to scientists, this adaptation was formed over decades of constant contact with poisoned baits. As a result of natural selection, the most resistant individuals survived and left offspring, whose bodies did not react to the effects of poisons.
Rats, on the contrary, are more wary of unfamiliar food, so their genetic resistance to poisons develops more slowly. Instead, large rodents adapt through learning and behavioral changes. Thus, it turned out that many of them learned to avoid traps.
“We have numerous videos showing rats avoiding mechanical traps such as traps and glue devices that are widely used by pest control professionals. Some rats may approach the trap about 300 times over the course of a week without ever touching it,” study author Jin-Jia Yu told The New York Post.
Scientists warn that long-term use of rodenticides could damage the city's ecosystem. Rodents continue to eat poisoned baits without serious consequences for their lives, but toxic substances accumulate in the bodies of predators – birds, coyotes and other animals that feed on mice and rats. In this regard, experts recommend more actively introducing non-chemical methods of pest control.
“Research shows that almost all wild animals that feed on roadkill have traces of rodenticides in their bodies,” said study author Changlu Wang.
New York ranks third in the United States in the number of rats, behind only Los Angeles (California) and Chicago (Illinois). However, authorities say the situation is gradually changing. One of the most effective measures in recent years has been the replacement of plastic garbage bags with containers.
Under former Mayor Eric Adams' administration, the use of containers became mandatory, first for food service establishments, and by March 2024 for all city businesses. Later this requirement extended to low-rise residential buildings. As a result, containerization has covered about 70% of the city's waste management system.
It was under Adams that the position of director of rat control first appeared in New York. It was occupied by former teacher Kathleen Corradi, who received the nickname “Queen of the Rat” among the residents. One of her projects was the educational walking program Rat Walks. According to Corradi, scientific evidence confirms that it is the reduction of the food supply and the elimination of favorable living conditions for rodents that make it possible to achieve a sustainable decline in their numbers.
The current mayor of the city, Zohran Mamdani, continued to promote his predecessor’s initiative. A few months ago, he announced his intention to switch to full containerized waste storage by 2031.
“By the end of next year, we will have a fully containerized waste collection system in at least one community district in each of the five boroughs of New York City. And by the end of 2031, we will completely transfer the entire city to container waste storage,” Mamdani noted.
Another initiative in 2024 was proposed by New York City Council member Sean Abreu. Unofficially dubbed Flaco's Law, the project calls for the use of rat birth control in areas where trash is already stored in containers. The pilot program began in the summer of 2025 in Harlem. Dozens of special “stations” with bait containing contraceptive drugs were installed there.
Despite the ability of rodents to adapt to traditional control methods, the measures taken are gradually bringing results. A total of 11,106 rodent complaints were reported in New York City year to date through June 18, 2026, a 29% decrease from the same period in 2025. In Manhattan, the number of complaints dropped from 4,487 to 2,662. Brooklyn remained the area with the highest number of complaints, with 4,071 complaints, but there was also a 26% decrease compared to 5,495 cases a year earlier.
