ANDREW LIMBONG, HOST:
Eric Adams, the mayor of New York City, has long been plagued by an arch nemesis.
(SOUNDBITE OF ARCHIVED RECORDING)
ERIC ADAMS: Everyone that knows me, they know one thing - I hate rats.
LIMBONG: It's become such a big issue that this week, Adams appointed the city's first-ever rat czar. Meanwhile, Anil Oza and Regina Barber of NPR's science podcast Short Wave have been peering into the secret life of New York City's rats to find out if, scientifically, we even know enough to take on our furry neighbors.
ANIL OZA, BYLINE: Rats have been all over the place in New York City, both literally - I see them all the time on the train tracks when I'm going home. There's posters everywhere advertising this new policy of putting out garbage later in the day. So I've been making a lot of calls to understand the extent of the problem, and one of those people was Michael Parsons, an urban rodentologist at Fordham University here in the city. And Michael actually has this five-step process for limiting the number of rats. And the first step was the one that really stuck with me.
MICHAEL PEARSONS: So step one, right? Know your enemy. And that really is about understanding the biology of rats.
REGINA BARBER, BYLINE: OK. I mean, I struggle with understanding biology in general, but how do other scientists understand our ratty enemies?
OZA: Well, actually, they feel just as clueless as you do, Gina.
BARBER: (Laughter).
OZA: And it turns out that question is a lot easier asked than answered. Take Kaylee Byers. She's a senior scientist at the Pacific Institute on Pathogens, Pandemics and Society at Simon Fraser University.
KAYLEE BYERS: We don't really have a good sense of the rat situation anywhere, to be honest. I mean, we know lab rats, right? But that's not the same as studying wild rats. What do their relationships look like when they're underground? And I think part of the reason it's hard to gather that information is because they are really elusive.
BARBER: OK. So, Anil, what's New York's plan for tackling these elusive critters?
OZA: For one, there's a new rule where people have to put out their garbage much later in the day than they used to, 8:00 instead of 6:00. And they're also hiring a rat czar. This person's job would be to get rid of the rats in New York City and to get their population under control. Let's focus on that first one for a minute because it cannot be understated how important garbage is to rats. I thought that Michael put this connection really, really well.
PEARSONS: There's a rat equation, and it goes simply garbage in equals rats out.
BARBER: I mean, I like the math. It makes sense. But what does he think about moving the garbage timing? Is it going to make any difference?
OZA: Actually, he doesn't think it will. And it comes down to our understanding of rats. So New York, along with all the places we're going to talk about today, have two main kinds of rats. There's brown rats, which is the ones that you see scurrying along the street a lot, and then black rats, which are sometimes called the roof rats because they're on the roofs of buildings and stuff like that. But both of these species are nocturnal, which means that...
PEARSONS: When you shift the garbage around in the daytime, you can move it around all you want to. You can put it in the trunk of your car. You can drive it around. You can take it with you grocery shopping. The majority of rats don't care because, you see, they're asleep. They're waiting for the picnic to happen in the evenings.
BARBER: Then what should we be doing about the garbage?
OZA: Yeah. So all of the experts I talked to, including Michael, said that when people or city officials talk about rat management, it's usually all about getting rid of the rats instead of focusing on the reasons that they're there. They usually said that rats are a symptom of other problems in the city. But Kaylee told me, based on her work with the Vancouver Rat Project, we need to focus on the problems that are causing rat overpopulation in the first place.
BYERS: We need to not just be thinking about, how do we eradicate rats, right? We've been doing that for thousands of years. Catch, kill, repeat - that's our motto, and it's not working. And so instead, having someone to think about, how do rats intersect with other aspects of urban planning in the city, waste management, green spaces, transit, housing?
BARBER: Yeah, because rats have been in cities forever, right? I guess they would end up everywhere. This actually makes me think of that opening scene of "Ratatouille" where you realize the rats are everywhere in Paris.
OZA: Exactly. And there's different kinds of rats. You have Remy, who loves to be in the city eating from restaurants, and then you have his brother who loves just eating the garbage.
BARBER: Yeah.
OZA: But just like that, New York City has a bunch of different kind of rats. And there was no one better to explain those nuances than Bobby Corrigan. As I was talking to researchers for this story, they all mentioned him by name, telling me, you got to talk to Bobby. He's one of the preeminent experts on urban rats. And he's done research for many years. And he's worked in pest management here in New York City. And he says those nuances are found in the rats' many, many wide-ranging homes.
BOBBY CORRIGAN: We have these rats that occupy all the spaces. They occupy ceilings in some of the most modern skyscrapers in any city around the world. They're all the way down into the sub-sub basements of our 1800s buildings. But we're not measuring any of that. So we don't have any idea when, let's say, someone initiates a campaign to control the rats of a neighborhood. What does that mean? What are we controlling, the surface rats? And if we only control the surface rats, what about the subsurface rats? What about park rats? So forth and so on.
OZA: And rat management is really a global issue. In 2017, New Zealand created this really, really ambitious program called Predator Free 2050 to get rid of a bunch of invasive animals - possums, stoats, ferrets, weasels and, of course, rats. This is Dan Tompkins, the science director of that initiative.
DANIEL TOMPKINS: Rats are a global pest. You have to admire these animals. They are pests because they are just so good at doing what they do.
BARBER: And has this plan fared any better with rats than New York?
OZA: So it's really hard to tell so early into this program, but they've had some success. And I think it might have something to do with the differences in the way that Dan was talking about rats compared to some of these New York City officials.
BARBER: So what was that?
OZA: Yeah. So when Dan talked about managing rats in these huge urban neighborhoods or throughout the country, it was a big collective thing that people were doing in their backyards or with their communities. But here in New York, it's really an individual thing. Remember that second part of the New York rat program?
BARBER: Yeah, the higher the rats are, to hunt down and murder all the rats?
OZA: Yeah. And some of the scientists I talked to had question marks about this rat czar. And it may be the wrong way to be thinking about this problem because it places all of the responsibility on this one person to be thinking about these rats and chasing after them, when really what we need is everyone to be involved in it in their own neighborhoods and managing their garbage. But that's something that Dan says that New Zealand has done really, really well.
TOMPKINS: We're trying nationwide eradication. We quickly realized that to get this job done, you've got to have the engaged support of communities. Also, they're really building a sense of ownership. And that means that they're in for the long haul. And they take setbacks and things not working, and they keep going until they get it right.
OZA: Because one person, a single rat czar can't be in all of the ceilings and basements and pipes and public spaces in New York City all at once and every day. Every individual in the community is really, really important, especially when you're battling another animal that's so elusive and so smart and that reproduces so quickly.
BARBER: It's not sounding like New York's current action plan is effective, but maybe I'm wrong. But do you think we can actually fix the urban rat problem in New York?
OZA: I hate to say that it's really hard to say if we know whether this will work or not, but it definitely won't be easy. When I was talking to Bobby, who's a pioneer of this field, he thinks that making a big impact on these urban rat populations will take a serious pivot and shift in this current thinking. Specifically, he thinks that we have to stop underestimating rats. He was even telling me about times that he's seen rats set off traps with sticks so they could run around and get a bunch of food. So instead of relying just on the usual traps, sprays, poisons or other things, we need to be doing everything that we can to rat proof the city.
BARBER: I am never going to underestimate a rat ever again.
OZA: Well, I hope the next time you see a rat, you think of me.
BARBER: (Laughter).
LIMBONG: That was Anil Oza and Regina Barber of NPR's science podcast, Short Wave. Transcript provided by NPR, Copyright NPR.
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