Animals and Insects

Rats Are Seemingly Taking Over U.S. Cities

Why does it seem like the rat problem is such a stumper for so many U.S. cities, and what can be done do to solve it?

Rats Are Seemingly Taking Over U.S. Cities
Richard Drew / AP

Major cities are declaring a war on rats, dedicating new programs and funds to try and slow down their population growth.

The rat problem is more than just a nuisance. Rats can also spread dozens of diseases through direct contact, and not just by touch. Just breathing in the same air as an infected rat or touching food or materials contaminated by an infected rat can be dangerous. Plus some of those diseases, like hantavirus, can be deadly.

New York Mayor Eric Adams famously "hates rats more than anything." This year, his office listed a job opening for a "Director of Rodent Mitigation," which required a "vehemence for vermin" and "an aura of badassery."

But it's not just New York; all across the country, reports of rat sightings have jumped since the pandemic began. That might be in part due to the increase in outdoor dining, some dips in trash collection during the height of the pandemic because of budget cuts, and sanitation staff out sick with COVID.

But it's hard to confirm how much populations may have grown because of the pandemic, especially since reports of a "rising rat problem" have been coming out for many years now.

A report from 1994 speculated about how budget cuts in New York led to an increase in rodents, and another from 1976 feared the rise of "super rats," which could ingest lots of poison and survive. Even a New York Times article from 1865 complained the city was getting the "unenviable notoriety" for having more rats than "any other city in the union," and if the growth couldn't be stopped, the city council would need to hire the Pied Piper.

These brown rats many cities are seeing aren't actually native to North America. They came to the U.S. in the 1700s, likely through New York City, and quickly spread like wildfire with their unique survival abilities as the U.S. colonies expanded west.

Rats are an unusually adaptable species. They can swim, climb, jump three feet and squeeze into small spaces. They don't need much food to survive, and though they don't live too long, they have large litters.

New Zealand Has 34 Years To Get Rid Of Rats
New Zealand Has 34 Years To Get Rid Of Rats

New Zealand Has 34 Years To Get Rid Of Rats

New Zealand's pest population is killing 25 million native birds per year.


These brown rats can't survive in the wilderness, so they stick to major hubs of human activity, like cities. But their growth in North America came to a halt at the northern border, when they met an unmovable Canadian province: Alberta, the largest area in the world to declare itself "rat free."

The brown rats didn't reach Alberta until as late as the 1950s. Just as rat infestations began springing up along its southeastern border, the provincial government sprang into action. The government assigned pest control supervisors for each county and used an aggressive campaign of toxins like arsenic across farms, buildings and any site that might draw rats. They also led an extensive public education program on spotting and dealing with infestations. This included local seminars, radio broadcasts and more.

Alberta residents and local officials were responsible for treating rat infestations themselves, with some steep fines if they didn't comply. Today, rats are still illegal to own in Alberta, even as pets, and can only be used in research or in zoos with special permits.

Some have argued this might be too extreme, particularly forcing families to surrender their pets if caught, but what's clear is that rat infestations plummeted and have been barely detectable for years.

U.S. cities could learn a thing or two about how to eliminate rate infestations on a massive scale, but not everything can be replicated. Alberta was able to eliminate infestations before they reached major urban centers, and the province is landlocked.

The rat problem is tougher to solve for coastal cities or any cities with ship access, since an influx of rats on ships is harder to stop.

But that hasn't stopped cities across the U.S. from trying everything to tackle the problem, from bringing poisoned food to rat burrows, to ultrasonic devices, to rat birth control, to scented trash bags.