‘They are as big as cats’: Newton and Cambridge discuss rats on the rise

"They scream all the time and I’m afraid to go out."

Newton and Cambridge residents say rat populations are on the rise. George Rizer/Boston Globe

No, they’re not a figment of the imagination. There actually are more rats.

As unsettling as that is, rodentologist Bobby Corrigan confirmed during a virtual Q&A for Newton residents that the rodent population is estimated to be up between 15 to 36 percent, he said, based on his own records from surveys, as well as talking with other scientists, and scientific investigations.

Rats have been a regional issue for a while, with Boston ranking as one of the most rat-infested areas in one report.

“A town like Newton is a perfect example as to what’s happening around the world, and that is, generally, rats are on the increase,” he said.


Mayor Ruthanne Fuller mentioned rats during an update from late August, noting that the city was taking measures to help control the rat population, including requiring rodent control for every demolition, and using rodent control measures that are safe for the environment.

Corrigan, who spoke during an event held by a mayoral candidate on Sept. 8, noted that when it comes to rats, there are a variety of myths, including that their numbers increase due to construction or the pandemic, and that they’ve become more aggressive. There’s also no such thing as “super rats” that poison doesn’t work on.

“There’s no rats in Newton that are as big as alley cats,” Corrigan said. “I would offer a challenge to anyone here tonight that if you bring me a 2-pound rat, just 2 pounds, I’ll write you a check for $500.”

But what the pandemic did do — and what construction often does — is cause rats to migrate, according to Corrigan. 

“There are changing patterns without a doubt,” he said. “When everybody shut down, when all the restaurants closed, and all our towns and cities, many of the rats that were depending on that trash, that food trash that goes out in our communities every night, [it] no longer was there.”


But there isn’t data to prove they’re more visible. He did say that with people working remotely, they were more likely to see a rat because they were home more.

What Corrigan recommended, rather than calling an exterminator, is for the city to be proactive and organized when it comes to rodent control. He advised getting a community group together to work on the problem. What the group could do is look at data from complaints, and map out where the highest populations of rats are. The group could also look at dumpsters to see if trash is being properly disposed of, among other measures, to come up with a plan for rodent control.

Cambridge also dealing with unwanted rodents

In Cambridge, the city has been fielding recent complaints from residents about rats, and the city is looking to take more measures against the animals.

The City Council recently adopted an order that imposes a variety of measures to help control the rodents, including choosing a point person to deal with rat issues, and serve as a liaison between the public and the Council on rats.

The Council also requested that the city departments look back on the rodent and pest control report from February 2020 and consider if there needs to be more money allocated toward control efforts, and how they are determining if the measures are working.


“Over the past several weeks, as I’ve been talking to more and more people, what has been a recurring theme is the problem with rodents in our city,” Councilor Denise Simmons said during the meeting when the policy was adopted, according to Wicked Local. “I had a young lady come by and literally showed pictures where the rodents were burrowing under her property.”

Recent complaints to the city’s reporting system include dead rats in the street, as reported on Tuesday.

“Rats running back and forth here,” another report from Wednesday says.

Despite Corrigan saying rats can’t get as big as a cat, one Cambridge resident says otherwise in another rat report.

“Rats are running wild between 17-19 Hunting Rd and willow street,” the report says. “They are as big as cats. They scream all the time and I’m afraid to go out.”

Editor’s note: This story has been updated to clarify some of the common myths about rats.


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