Depending on where you live, there’s a good chance that you see a crow nearly every day. Fortunately, they’re one of the most fascinating birds on the planet. Corvids, the bird family that includes ravens, crows, and magpies, are incredibly intelligent — and it seems like every time we learn something new about them, it raises even more interesting questions.
Do crows really recognize human friends? Why do thousands of birds swarm certain neighborhoods? And what’s up with crow funerals? Read on for the answers to these and other questions about one of the most intriguing birds around.
Crows Recognize Faces — and Keep Both Friendships and Generations-Long Grudges
Have crows ever acted weird around you? It’s possible they remember your face, and that could be a good thing — or a very bad thing.
In 2008, a University of Washington research team led by John M. Marzluff published a study on crow behavior, risking their very eyeballs to do so. Wearing what they called “dangerous” masks (made of rubber and meant to resemble cavemen), the researchers captured and banded a group of crows — something the birds didn’t like too much.
While the crows acted normally to maskless or differently-masked researchers, the crows would scold (with loud, harsh calls) anyone wearing the dangerous mask, even when it was worn upside-down. As time went on and word spread among the flock, more and more crows would join in with the behavior. Over the course of several years, researchers walked around the UW campus wearing the bad mask, and, to this day, still get scolded and dive-bombed by birds more than a decade later, even though the crows from the study have likely died. Research has shown that the crows reacted to these threats and stored them in their memories in bird versions of the amygdala, a process much like that of humans.
This research confirmed what crow pros had always suspected: That crows don’t just recognize humans, but have deeply held opinions about individual people. Kevin McGowan, a researcher at the Cornell Laboratory of Ornithology, says that crows he has captured and banded are often still mad at him, while birds that have gotten many snacks from him follow him around. Plenty of non-scientists have shared the stories of their own corvid friendships, too, both in modern times and throughout history.
Crows Have Excellent Collaborative Communication Skills
As evidenced by the growing number of vengeful birds in the mask experiment, crows have excellent communication skills — and can go into far greater detail than just “this is bad.”
In the 1980s, researcher Lawrence Kilham studied a group of crows living on a ranch in Florida. (The technical term for a group of crows is a “murder,” by the way.) In one of his observations, five crows were helping a mother crow build a nest by bringing her sticks. After an excessive, messy pile of sticks accumulated, the mama crow was able to communicate that the deliveries were no longer helpful. She spent the next two weeks finishing up the nest with materials from the pile.
After decades of crow study, Cornell’s Kevin McGowan has even learned to understand some of what they’re saying through the timing, spacing, timbre, and energy of their calls — at least, some of the simpler stuff, such as “a hawk is approaching,” “the hawk is getting closer,” or “help me harass this owl.” He says that music is a better comparison than spoken word.
In addition to caws, crows have noises such as rattling, clicks, and bell-like sounds in their vocabulary, plus non-vocal communication. Sometimes they even imitate other birds.
Crows Have Funerals (Kind Of)
There are many ways you can make enemies with a crow, but one of the quickest is to be seen with a dead one. When faced with a dead member of their own species, many wild animals will avoid the area. Crows, on the other hand, will mob the body in large, loud gatherings — then silently depart.
While crows do have tight social bonds, the funerals may be more about information-sharing. What happened here? How can we avoid danger? Who are we ganging up on over this?
In 2015, University of Washington researchers found that when crows see a human in the proximity of a dead crow just once, they can continue associating that person with the death for up to six weeks. Humans, however, are not public enemy number No. 1. When researchers presented a hawk near a taxidermied crow, the mobbing intensified.
They also found that, while threat assessment is a key part of these gatherings, crows don’t do the same thing for just any species of dead bird — this ritual is reserved for their own.
Crows Might Be as Smart as Great Apes
Clearly, crows are very intelligent, but just how smart are they? In addition to their dynamite communication, threat assessment, and memory skills, crows demonstrate self-awareness, capacity for learning, and problem-solving abilities that may approach those of great apes.
New Caledonian crows — who live on the islands of New Caledonia in the South Pacific — are especially well-known for being adept with tools. In one experiment, a crow figured out how to use water displacement to get access to food. In another, the same species of crowfashioned a hook out of a piece of wire to dig out a treat — and in yet another, they used a small stick to push a long stick into the right position for reaching food.
In 2018, University of Auckland researchers decided to see if crows could remember templates and replicate them. First, the researchers fashioned a small, snack-dispensing mock vending machine that accepted a specific size of paper. The crows, presented with pre-cut paper, would learn which one operated the machine. Later, presented with one larger sheet of cardstock, the crows would tear the paper to roughly the same size from scratch.
Caledonian or not, crows have a sophisticated understanding of cause and effect. BBC Earth observed one crow in Japan who learned to open nuts by dropping them into traffic. When he discovered it was difficult to retrieve them, he started dropping them at pedestrian crossings so he could harvest the insides without getting run over.
Crows Have Close-Knit Family Relationships
American and Northwestern crows are known for close family bonds. Pairs of birds mate for life, and older crow offspring will pitch in raising the younger ones. During the egg incubation period, the mama crow has food delivered a few times an hour by her mate and other family helpers. Cornell researcher Kevin McGowan has witnessed crow families of up to 15 birds at one time.
It gets sweeter: At hatching time, other crows start visiting just out of curiosity about the new baby. Researcher Lawrence Kilham observed mother crows greeting these visitors by moving slightly to the side to give them a peek. In crow families, adults can stick around their parents’ territory for a while, sometimes for several years. Even once they do move out, they may come back every so often, sometimes to help with nest-building.
While mating and hatching season are both big deals in crow family life, learning-to-fly season is up there, too. Many young birds of other species don’t see their parents again after getting pushed out of the nest for the first time, but crows keep a close eye on their juveniles while they’re running around on the ground — and occasionally, an unsuspecting human will get a little too close and get dive-bombed.
Tens of Thousands of Crows Roost Together
Crows have large families, but, in the fall and winter, they have even bigger roosting communities. This is why on chilly afternoons, you may see thousands of crows swarming around one place. Smaller groups of crows come to these giant roosts from miles around. Roosts even host international guests; some crows from Canadian forests will winter in Seattle for the warmer city environment. More than 15,000 crows sometimes roost in downtown Portland alone, and 16,000 crows roost on the University of Washington, Bothell, campus near Seattle. In the Fort Cobb area of Oklahoma, the roost population exceeded 2 million in 1970.
You did not mention that crows are excellent talkers. They get even the tone correct. We found and raised a baby crow. It learned many words and phrases, and would greet you with hello and your name. It could speak loudly and clearly, in my voice or my wife’s. It was a very loving bird, extremely smart. Better than any parrot we ever had.