Almost every morning they wake me. Their raucous cries are harsh and grating, like fingernails on a chalkboard. They cluster in a flock known as a murder, cawing their displeasure at an owl or hawk who has chosen my woods for its roost. The crows flutter and dive, becoming more daring with each fly-by. Eventually one of two things happen: the raptor gives up her perch and flies off or the crows grow tired and move on to other mischief.
One cold blustery day I watched seven crows in the bare branches of a tall oak growing on the banks of the York River at Gloucester Point. The upper-most bough bobbed wildly in the wind. As I watched, each crow took a turn, bouncing skyward several times before being displaced by another. It dawned on me that these crows were playing.
Scientists tell us that many birds play. In at least a third of bird species, voluntary, interactive, and stress-free movements have been well documented among chickens, ducks, seabirds, woodpeckers, owls, hawks, and songbirds. But no group of birds has been reported to play as frequently or with such complexity as the corvids.
Corvidae, more commonly known as the crow family, includes crows, ravens, jays, and magpies in North America. Crows’ close association with humans predates written history and has inspired art, legends, myths, and language. Archaeological evidence reveals that our earliest ancestors shared the company of crows and ravens. Even today these birds benefit from our road kills, peruse our garbage for food and nesting material, incorporate our voices into their own language, and routinely annoy us with their actions and sounds. But do we benefit from them?
Corvids display high intelligence, playfulness, mischievousness, passion, and sorrow. People from all walks of life have eagerly shared their encounters with these fascinating creatures that give new meaning to the term ‘bird brain’.
Many of our encounters with crows begin with their raucous cries that wake us from our slumbers and disturb our backyard reveries. The crow has more than 20 calls but is certainly not known for the beauty of its song. Its cacophony of caws is strident and annoying. In fact, its frequent cawing is a signal to others in its extended family that an interloper has been spotted.
I watched a flock of crows harass a barred owl perched up in a beech tree one summer. Risking one’s life to harry an eagle, hawk, or owl seems a requirement for many corvids. This behavior may seem analogous to David facing Goliath, but for the corvid the gains outweigh the costs. Predators preoccupied with a mob of crows swooping, fluttering, and cawing are distracted from hunting and their presence made obvious to others. They either hunker down, miserable, awaiting the end of the assault, or fly off to find less hostile territories.
Either way, the risk takers have reduced the chances of a predator’s success and in doing so have participated in a social exercise by displaying valor and flight skills. The more daring crow may gain a mate or higher rank in its avian hierarchy. The youngsters learn by observing the mobbing. Of course, all this implies that corvids possess reasoning powers.
For centuries, philosophers and scientists have believed that other animals were incapable of conscious thought or emotion. But as we learn more about how information travels through the brains of other species, the more we come to realize that many sentient beings can mull over complex problems and derive solutions.
The crows of New Caledonia have demonstrated on more than one occasion the ability to fashion hooks out of plant material or sticks in order to fish for grubs and spiders. In an interview with the British Broadcasting Co., Professor Christian Rutz, lead researcher on crow studies on the island of Okinawa, observed, “We tend to assume that the closer an animal is to us, the more intelligent it should be, and thus we more easily understand that primates make and use tools. But we have to be more humble and accept that many ‘small brained’ animals are intelligent enough to make and use tools, and sometimes are more proficient at this task than our cousins.”
But could crows evolve beyond simple fishing hooks to something more complex? Following up with the New Caledonia crows, researchers from Cambridge University devised a vending-type machine that required the crows to drop in small pieces of paper to release a treat. First the birds had to be shown how to operate the device. Once they learned to drop or nudge a stone or bits of paper into the slot and trigger the reward, they were given pieces of paper too big to flit into the slot. It didn’t take long before the crows would snip the paper into smaller bits to fit into the slot. But was this evolutionary innovation?
To make the test even more definitive, the researchers provided each of the eight crows with a vending machine that would release a treat only when a particular size of paper was inserted. The birds had no template; they just needed to remember the size of the paper token their machine required. All eight adults spontaneously made the right-sized piece of paper for their vending machine.
This past summer, a theme park in France deployed six rooks (European corvids) at the Puy du Fou theme park where they taught them to collect cigarette butts and other small bits of trash. The birds deposited the litter into small boxes that would then deliver food as a reward. Head of the park, Nicholas de Villiers, remarked that, “It was not just about keeping the area clear, but it was also about showing that nature can teach us to take care of the environment.”
For more than two centuries, having a ‘bird brain’ was considered a sign of stupidity. Now it may turn out to be a compliment. In studies conducted at leading universities around the globe, dozens of species of birds have been found to have more neurons packed into their small brains than are found in mammalian or primate brains of equal mass.
A human brain weighs about three pounds, or 1.9 percent of our total body weight. Earth’s largest mammal, the blue whale, has a brain that accounts for only 0.01 percent of its body weight. For crows and ravens, as a percentage of body mass, they approach or exceed our own, tipping the scales at 1.4-2.7 percent. Corvids therefore, have brains on par with mammals rather than birds.
Songbirds, of which the corvid is a member, have surprisingly large numbers of neurons in their pallium; the part of the brain that corresponds to our cerebral cortex, which supports higher cognition functions. Although scientists acknowledge the relationship between intelligence and neuron count has not yet been firmly established, when compared to mammals other than man, birds possess higher cognitive power per pound. The mysteries of the avian brain have just begun to be explored.
The accounts of researchers, scientists, and observers have managed to paint a fantastic picture of this clever, social, opportunistic, and associative learner we call crow. Its impressive brain enables these long-living, adaptable creatures to solve problems, test their environments, observe responses, and accumulate experiences. As a group, they function much like a family.
By human standards, crows are not long lived. The oldest wild bird on record lived to be 14; most rarely make it past seven. During that time, they live in communal flocks, youngsters helping parents to raise the young, seeking out food, guarding for threats, and learning from fateful situations.
YouTube videos and news snippets reveal crows and ravens gathered around their dead, circling and circling like some sort of macabre ritual. Rarely do they touch the body, and it’s unclear whether they are paying emotional respects or simply acquiring knowledge about danger or contemplating hierarchical opportunities. In all likelihood, corvids gather around their dead because it is vital they learn the causes and consequences of another crow’s death. If crows do mourn, this display is short-lived.
Reports of crows maiming or murdering a flock member have been well documented worldwide. These boisterous gatherings, called crow courts, often result in the driving away or even death of the offending party. Whether these outcasts are members of the extended family or interlopers who have invaded another flock’s territory is unknown. Most of the time the aggression ends when the offending party flees or is killed.
Back at the tree, the crows continued their play. Frivolous antics are routine among crows and ravens. They’ve been observed windsurfing at Rocky Mountain National Park, gripping thin slivers of tree bark with their feet, spreading their wings, and riding the wind currents down a mountainside. In the mountains of Canada, ravens have been photographed sliding down icy, pitched roofs and steep, snowy banks. Numerous reports of crows riding bouncing power lines or tree branches, like the tree at Gloucester Point, are quite common. In the wild, turkeys and crows have interacted in ways that suggest play. Captive ravens have been seen playing with balls or luring a family pet into play with a string. These glimpses into crow lives suggest that corvids possess a brain capable of complex thought, assuming characte
ristics once ascribed only to primates and humans.
Our cultural interactions with crows have formed our opinions regarding these enigmatic birds. Their association with thievery, uncanniness, fidelity, death, and charisma are deeply embedded in our psyche. The crow’s ability to bond with people has enabled corvids to hold prominent roles in our literature, fables, religion, homes, and hearts. As we have explored its habits, brain, and emotional behavior, we have observed how this species has adapted and exploited whatever life has thrown its way. The nature that we may take for granted is home to creatures who think, reason, dream, play, take risks, love, and mourn. For all their perceived faults, they can also enrich our lives.