New York City has tried just about everything to win the war on rats.
We’ve hired a literal “Rat Czar,” rolled out strict new trash bin rules, and debated the merits of pizza rat for years.
But according to a fascinating new report from National Geographic, our greatest weapon for tracking the city’s rodent population might actually be the East River.
A team of researchers led by environmental geneticist Mark Stoeckle at The Rockefeller University spent a year pulling water out of the East River.
And they didn’t use million-dollar equipment to do it—they just used a plastic bucket from the hardware store.
The scientists were testing the murky water for eDNA (environmental DNA).
As Stoeckle explained to Nat Geo, “There’s DNA all around us.”
Animals are constantly shedding skin cells, hair, mucus, and feces.
When heavy rains hit the five boroughs, all that terrestrial waste on the streets washes straight into the river—which is admittedly gross to think about, but an absolute goldmine for scientists.
By analyzing these tiny genetic clues, the researchers unlocked a massive biological secret right in our backyard.
While they found an incredible 71 species of fish thriving in the water, they also found a whole lot of New York City’s surface-dwelling residents.
The East River is basically a rodent radar.
The study consistently detected rat DNA floating in the river.
But it’s not just a fun (or horrifying) fact—it could be a game-changer for the city.
The researchers suggest that by monitoring the spikes and fluctuations of rat eDNA in the water, pest control could actually use the river as an early warning system.
It could help them detect the early signs of a neighborhood infestation before it spirals out of control.
It’s basically crime scene technology, but for urban pests.
(And yes, it tracked other wildlife, too.) Alongside the rats, the water was filled with the genetic fingerprints of local squirrels, raccoons, and even beavers.
It also knows what we’re eating for dinner.
Because wastewater overflows into the river, the waterway acts like a giant, liquid diary of everything New Yorkers do.
The researchers actually found eDNA from cows, pigs, and chickens in the water.
When they matched the proportions of that animal DNA against U.S. meat consumption statistics, it was an almost identical match. The river literally reflects our diets!
So, the next time you’re sipping a drink on the Williamsburg waterfront or riding the NYC Ferry, take a look at the water.
It might not be crystal clear, but it’s doing the dirty work of tracking the city’s rats for us.
