Someday I will come up with a good reason why I am friends with the neighborhood crows. For now, I can say that it started when I looked up from my office window to see this big flock of crows hanging out on the roof of an apartment building nearby. I had heard that these creatures, part of a larger family of birds called corvids, were among the smartest animals in the world. If they were that intelligent, I wanted to meet them. How could I get those awesome animals to come visit me? I decided to find out.Six months later, I have made friends with about seven crows and two small, brightly-colored corvids called scrub jays — one of whom eats out of my hand. Like many scientists who study these animals, I've become convinced that these creatures are not only smart, but also have a theory of mind.
When I started trying to make friends with the crows, I didn't know much about these birds other than what I'd read in popular accounts. I thought they liked shiny things (which turns out not to be true), and I'd heard Cornell ornithologist Kevin McGowan say on NPR that they liked peanuts. So I took a big piece of shiny tin foil and wrapped it around the wooden railings on my balcony, stashing some peanuts underneath it. Whenever I saw the crows, I would whistle and wave and stand next to the foil. Yes, I'm sure I looked like an idiot, but apparently they noticed.
One morning while I was in bed, I heard a bunch of thunks and the sound of ruffling feathers. When I came out to the balcony, I could see that the crows had ripped open the foil and taken the peanuts. I continued with this routine for a while, and eventually they would come to get their peanuts when I was working. I'd watch them advance slowly down the railing, one eye on me, then snatch the peanut. Every day, a group of three would come to eat — two seemed to be a mated pair, and the third I nicknamed Whitey because he had a big white patch on one wing. He seemed to be quite old and feeble, and had a hard time landing and taking off. I left a lot of peanuts out for Whitey on a lower railing where it was easier for him to land. He and his two flock friends would pick up the peanuts in their beaks, then fly into the tree where they would hold the peanut against a branch with one claw and peck it open for the nuts inside.
This became our daily routine. Here you can see a video by Bruce Bourque showing how crows (and one scrub jay!) eat the peanuts he put out.
Hiding and Stealing
Along with the crows came two small, obnoxious birds with bright blue wings and fluffy gray breasts. They were lightning fast and would grab two or three peanuts in the time it took Whitey to get up the gumption to land and pick up just one. The crows would yell at them — aw aw aw! — and the interlopers would screech back — ack! ack! ack! It was a showdown, and I was pissed that these little guys were stealing my friends' food.
Here's a video showing the kinds of birds I saw, by Seth Herbey. So I started reading up on these blue birds and discovered that they are scrub jays, also members of the corvid family. They're quite smart, just like their crow brethren, and are famous for their ability to hide food in up to 200 hiding places and remember them all. Researchers have shown that they also seem to remember when they cached their food, returning to food that spoils quickly earlier than to food (like peanuts in the shell) that keeps for a long time. Once I knew this, I started watching the jays more closely. Sure enough, they would grab a peanut and race somewhere nearby — the neighbors' lawn, the backyard cottage storm gutter, our flower beds, various trees — and hide their food. The crows would always follow them.
The leaf-choked storm gutter was a favorite hiding place, and the crows started hanging out on the roof next to it, rooting through the leaves for the jay's stashes. It got to the point where I'd put out peanuts and the crows would just wait for the jays to grab them, and then follow them and watch while they hid the peanuts. This is thieving behavior that scientists have studied for many years, and they've discovered that scrub jays have a habit of hiding food, then going back and hiding it again elsewhere, especially when they know they're being watched. In this way, they fool the observer into thinking the food is hidden in one spot when it has actually been moved somewhere else.
Some scientists say that the jay's ability to figure out that they are being watched by potential thieves shows that they have a theory of mind — in other words, they can model another bird's thinking to themselves, and figure out what its motivations might be. It also shows that they can plan for the future, since they not only create these caches of food but maintain them by moving them around to fool the crows who want to pilfer.
Mobbing
One day, Whitey and his two friends stopped coming around. I suspect that probably Whitey died. For a while no new crows came around, but I did witness an astonishing crow gathering. A group of about nine crows gathered on the rooftops of the tall apartment buildings ringing my backyard. A couple of them were absolutely enormous — I'd never seen them in the neighborhood before. They all started calling back and forth to each other — aw! aw! — and they were clearly communicating. One would start with two cries, then the others would reply with two. Then they would each cry out three times in a row. I felt like I was watching a council of crow elders or something.
That was when a new bird emerged on top of one of the roofs. It was a gorgeous hawk, with a pale breast and huge, brown-spotted wings, which it opened at one point to an astonishing wingspan. It stood there silently on its corner while the crows called. What the hell was this? I wondered. I decided to try to participate, since obviously non-corvids were at this party. When one crow issued his calls, I would whistle back with the same number of sounds the whole gang was making. Finally, after about ten minutes of the crows and I calling back and forth, the hawk took off in a graceful arc, and the whole flock shot after him.
I later learned that I'd unwittingly participated in a mobbing. Here, you can see a video of a hawk being mobbed by two crows, taken at Drew University in New Jersey. Hawks are the crow's natural enemy, eating their eggs and babies, and crows from different flocks will occasionally band together to chase a hawk out of their territories. This particular hawk had been hunting in our neighborhood, and I'd caught him leaving the remains of half-eaten pigeons in our backyard a couple of times. So the crows had finally banded together to chase him out. I felt unhappy about this — urban hawks are rare, and this had clearly been his territory — but it was also a basic part of how ecosystems work. Animals compete with each other for resources, and these crows wanted to protect their offspring.
Later, I watched two scrub jays chase a lone crow away from the tree in my backyard when they wanted all the peanuts I'd put out. Jays mob crows all the time. Sometimes, crows mob each other. Mobbing is part of the corvid way.
Love and Communication
Soon after I started feeding the scrub jays, I realized that they were a mated pair. Female scrub jays make a distinctive call, often called a "rattle." (You can hear it in this video from Lorcan Keating). So I was able to identify the female by her call, and by the fact that she was far more curious and brave than her mate. She would walk right up to me on the rail and wait for her peanut. So I started to offer her peanuts from my hand. She took one! Sometimes, I would just stick my hand out of the sliding glass door with a peanut in it, and she would swoop down, grab it, and launch herself back into the sky by pushing off from my finger. She never quite landed on me, but she always eats out of my hands now. And, I might add, she'll eat out of the hands of anybody who comes out of my office door with a peanut. Her mate prefers to sit in the tree and dive for the peanuts I throw.
I'm not the only person who has befriended a scrub jay like this. I love this video by Rachel575, where she chats with a scrub jay who likes to come into her apartment for peanuts.
One day, the female scrub jay showed up with a small cracker in her mouth. She laid it down right next to me on the railing, then hopped over to grab her peanut. I'm not entirely sure if she meant to bring me the cracker, or if she forgot about it in her excitement over the peanut. But as ornithologist John Marzluff notes in his book Gifts of the Crow, it's fairly common for these birds to bring odd presents to their human friends. If crows do it, I would assume that jays might do it too.
A new flock of crows started hanging out in my backyard about a month ago. There are four of them, and they are all clearly juveniles: small, crazily curious, and awfully clumsy. Unlike their predecessors, who would gracefully scoop up peanuts and crack them open while balancing in the tree, these crows will fly elsewhere (usually to a roof) to crack the peanuts open and snack. But they do like to visit by sitting in the backyard trees, or sometimes on the railing where I put out peanuts for them. Often when they arrive they'll stand somewhat accusingly on the railing, looking right at me. "Where are the damn peanuts?" they seem to be asking.
One of them I've nicknamed Stretchy because he loves to sit in the tree near my window and do crow yoga. He'll stretch one wing, then the other, then each leg. He'll pull one wing low, loop his leg over it, then scratch his head. It's insanely adorable. One day I went outside next to him to stretch too. When I spread my arms out, he jumped away, watching as I slowly stretched my legs. Then he went back to stretching his wings. Were we communicating? Who the hell knows? It was fun, though.
Scrub jays tend to hang out in mated pairs, while crows form flocks made up of family members. That's why crows visit my backyard in flocks. After observing both groups for a while, it was clear that they had fairly complex relationships. The two jays fight sometimes, screaming and chasing each other down the whole block of backyards next to mine. They also play. One of the jays likes to chase its tail.
UC Davis ecology researcher Teresa Iglesias discovered that jays also hold noisy "funerals" when they discover a dead scrub jay. Here is a video she took of what the scrub jays did when they discovered a dead jay in her friend's backyard.
The crows will sometimes help each other, or sneak behind each other's backs. One crow I call Clumsy because he always knocks over several peanuts before managing to snag one off the railing. When he comes alone to eat the peanuts, he always takes as many as possible and races away. But when Stretchy comes, he'll stand over the peanut offering and call to his flock. Soon all four will be there, including Clumsy, knocking the peanuts around and eating until I stop feeding them.
I never feed the birds before noon, because they are incredibly noisy and I don't want them bugging our neighbors in the mornings. The jays and crows seem well aware of this. They never show up before about 12:30 looking for peanuts. The jays will often spend much of the afternoon returning every hour to sit next to the window and look at me, puffing up their feathers so they look like they're de-rezzing and then coming into focus again. I'll watch them clean the down on their chests, occasionally eating a tiny nit they find there, and marveling at that goofy way they have of scratching their heads. It's a kind of companionship.
Theory of Mind vs. Series of Instincts A recent article published in PLoS, "Corvid Re-Caching Without A Theory of Mind: A Model," illustrates the odd dichotomy between scientists who approach the question of bird intelligence. In it, a group of researchers suggests that scrub jays who re-cache their food after being observed by other birds (like the jays do when the crows are watching) aren't doing it because they know the crows might steal. In other words, they have no theory of mind that allows them to take the crows' perspective and guess at their motives. Instead, say the researchers, jays simply have an instinct that makes them get more stressed out when they are being watched by other birds. Then, when they get stressed, they have the urge to re-cache their food. This would suggest that jays operate on a less sophisticated level in some ways. They don't realize what the crows might do, and they don't even know why they are re-caching. They simply get stressed out and have the urge to re-cache and then they're done.
Many scientists, like Gifts of the Crow author and scientist Murzluff, take the opposite point of view. Murzluff believes that crows and other corvids have a theory of mind, which allows them to understand and anticipate the behavior of other creatures around them. This is why, for example, crows are able to figure out that it's a good idea to scavenge for food on the Seattle ferry between cars — they've seen people toss food out the windows before, and anticipate they'll do it again. It's why scrub jays know that the crows are watching them to try to steal their peanuts. Crows also use tools, bending sticks to turn them into hooks for retrieving food.
They play, as you can see from this video of a crow surfing on a snowy roof in Russia.
And they'll even feed other animals, as this pet crow does with his dog and cat pals.
Their highly-developed brains — different from mammal's but no less complex — seem capable of planning for the future (caching), guessing at motivations and acting accordingly (re-caching food) and problem solving (tool use).
Do crows, jays and other corvids share with humans the ability to know themselves and know other creatures too? Or are they merely acting on instinct, which we mistake for more complex thought patterns? It's impossible to say for certain. But there is no doubt that they are extremely intelligent, social animals, who count humans among those creatures they are willing to trust.
Memory
One of the most fascinating facts about crows is that they have excellent facial recognition abilities. They dive-bomb people who hurt them even years after the injury, and they will return to people who feed them for years too.
I recently got back from a long trip, and I wondered if the scrub jays and crows would remember me. They did. A few hours after I walked into my study, the scrub jays landed on the railing and and shot me looks that said, "Give me a peanut now, human." When I stepped outside with the peanuts, the female jay started dancing. She ran in a tiny circle and jumped up and down. Then, for the first time, she landed on my hand and stayed there for just a second before snatching her peanut and zapping away. I tossed her mate a peanut, and he dove for it, then flew next door to tap it into a hiding spot at the edge of our neighbors' lawn.
Here's a great video by HollyCalifYankee where he shows a scrub jay eating out of his hand in slow motion.
A few minutes later, all four of the crow gang landed on the branch that is closest to my balcony. It bowed under their combined weight. Normally they wouldn't all share the branch, nor would they land so close by. I'm not sure you could say they had missed me, but certainly they'd missed those peanuts. I put some peanuts out for them in their favorite place, and before I'd even gone back inside, they'd whirled down to grab as many as possible.
I watched from behind the glass door, admiring the light on their feathers. And laughing at Clumsy, who'd piled up way more peanuts than he could carry in his beak, losing many in the process. But he kept trying over and over to make the perfect beak-ready stack. If meeting once a day to share food makes a friend, then these corvids have definitely become mine.
Top photo by SipaPhoto via Shutterstock
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