The Most Ingenious Hawk in New Jersey

Yahoo

23-05-2025

In November of 2021, Vladimir Dinets was driving his daughter to school when he first noticed a hawk using a pedestrian crosswalk.
The bird—a young Cooper's hawk, to be exact—wasn't using the crosswalk, in the sense of treading on the painted white stripes to reach the other side of the road in West Orange, New Jersey. But it was using the crosswalk—more specifically, the pedestrian-crossing signal that people activate to keep traffic out of said crosswalk—to ambush prey.
The crossing signal—a loud, rhythmic click audible from at least half a block away—was more of a pre-attack cue, or so the hawk had realized, Dinets, a zoologist now at the University of Tennessee at Knoxville, told me. On weekday mornings, when pedestrians would activate the signal during rush hour, roughly 10 cars would usually be backed up down a side street. This jam turned out to be the perfect cover for a stealth attack: Once the cars had assembled, the bird would swoop down from its perch in a nearby tree, fly low to the ground along the line of vehicles, then veer abruptly into a residential yard, where a small flock of sparrows, doves, and starlings would often gather to eat crumbs—blissfully unaware of their impending doom.
The hawk had masterminded a strategy, Dinets told me: To pull off the attacks, the bird had to create a mental map of the neighborhood—and, maybe even more important, understand that the rhythmic ticktock of the crossing signal would prompt a pileup of cars long enough to facilitate its assaults. The hawk, in other words, appears to have learned to interpret a traffic signal and take advantage of it, in its quest to hunt. Which is, with all due respect, more impressive than how most humans use a pedestrian crosswalk.
Cooper's hawks are known for their speedy sneak attacks in the wild, Janet Ng, a senior wildlife biologist with Environment and Climate Change Canada, told me. Zipping alongside bushes and branches for cover, they'll conceal themselves from prey until the very last moment of a planned ambush. 'They're really fantastic hunters that way,' Ng said. Those skills apparently translate fairly easily into urban environments, where Cooper's hawks flit amid trees and concrete landscapes, stalking city pigeons and doves.
That sort of urban buffet seems to have been a major incentive for this particular Cooper's hawk, Dinets, who published his observations of the bird in Frontiers in Ethology, told me. One of the (human) families in the neighborhood regularly dined outdoors in the evening, leaving a scattering of food scraps on their front lawn that would routinely attract a group of small birds the next morning. But the hawk needed perfect conditions to successfully dive-bomb that flock: enough cover, from a long-enough line of cars, to attack unseen. That scenario would play out only on weekday mornings, when both foot and car traffic were heavy enough that the crosswalk signal would stall lines of cars down the streets.
Over several months, Dinets noticed that the bird seemed to have figured out this complex system of ifs, ands, or buts. The hawk appeared only when the necessary degree of congestion was possible. And only after the pedestrian-crossing signal was activated would it ready itself for an attack—perching in a nearby tree to wait for the backlog of cars that it knew would soon manifest. Then, only after the queue stretched long enough to totally conceal its path, the bird would head toward its prey.
The crosswalk signal seems to have been key to this plan: The hawk could predict with startling accuracy how well cloaked it would be—and, thus, the success of its attack. 'The hawk understood the connection,' Dinets told me. That's hard to prove without experimentation, beyond Dinets's observation of this single bird—but that this hawk figured out the chain reaction that this signal could set off, under weekday-morning conditions, is definitely plausible, several researchers told me.
Plenty of animals, including other types of birds, have proved themselves savvy in human environments. Pigeons, for instance, wait for humans to turn on drinking fountains, then sip the water. Ng has spoken with farmers and ranchers in Alberta and Saskatchewan who have seen hawks use the sounds of gunshots during gopher hunts as a cue that a feast is impending. And crows have been spotted dropping hard-shelled nuts into roads so that cars will crack them open.
Still, Ng, who wasn't involved in the observations, told me that this hawk's feat is impressive, even if no other bird ever replicates it. The hawk clued into a human signal, in a human system, that was multiple steps removed from its target. Managing these attacks required a degree of foresight, a mental map of the neighborhood, even a sense of a human week's rhythm—understanding, for instance, the difference between weekday rush hours and weekend lulls.
The bird also appears to have picked up on all of this relatively quickly: Many Cooper's hawks spotted in cities come to urban areas only for the winter, which hints that this one may have conjured its plan of attack as a recent immigrant to the area. Generally speaking, the faster a creature learns something new, the more cognitively adept it is likely to be, Joshua Plotnik, a comparative-cognition expert at Hunter College, told me. And this hawk managed all that as a juvenile, Ng pointed out—still in the first couple of years of its life, when most Cooper's hawks 'are just not good at hunting yet.' A common cause for mortality at this age, she said, is starvation.
But maybe the most endearing part of this hawk's tale is the idea that it took advantage of a crosswalk signal at all—an environmental cue that, under most circumstances, is totally useless to birds and perhaps a nuisance. To see any animal blur the line between what we consider the human and non-human spheres is eerie, but also humbling: Most other creatures, Plotnik said, are simply more flexible than we'd ever think.
Article originally published at The Atlantic