Buzz
Crows are far from typical birds. They possess sharp intelligence and a highly interactive social structure. Unusual experiments revealed just how expansive a crow's mind truly is. Scientists subjected these birds to kidnappings and tested them with fables and the corpses of other crows.
The outcomes were astonishing and, at times, a little unsettling. Crows exhibited traits usually attributed to humans, showed unusual responses to death, and even engaged in hunting a creature that is a natural predator to all others, captivating those who take the time to understand them.
10. Amusement Park Employees
Approximately two decades ago, Christophe Gaborit observed wild ravens rummaging through garbage. Many years later, Gaborit worked as a falconer at a French theme park called Puy du Fou, renowned for its ancient gardens and villages. Guests are also treated to historical reenactments, yet they tend to leave behind a fair amount of litter.
Looking for a solution, Gaborit recalled his experience with the ravens and proposed an innovative idea—train rooks to clean up the trash. Rooks, like crows, are highly intelligent members of the crow family.
In 2000, Gaborit began raising and training his first pair of birds. Using a specially crafted cabinet, he rewarded the rooks with treats for depositing items such as cigarette butts into it. Over time, he successfully trained six rooks to recognize and collect litter. These feathery trash collectors completed their training in 2018 and now roam the park, tidying up the grounds.
9. Dead Crows Disturb Them
Some believe that crows conduct funerals for their deceased. While this idea is fanciful, it’s easy to see why it endures. Unlike many birds, which pay little attention to their fallen kin, crows gather around their dead, calling out to one another, and showing an unusual level of focus on the situation.
However, they are not mourning the dead. The surviving crows recognize that something caused the death of one of their own. They realize that the threat is real and could harm them as well. Their apparent concern is more about identifying the danger and ensuring they can avoid it going forward.
A significant study on dead crows, conducted across more than 100 breeding sites in Washington State, revealed that crows regarded humans who interacted with a dead crow as a potential threat. Even after the dead crow was removed, the crows remained cautious, avoiding areas where such a human had been.
The birds did not react negatively to volunteers who simply stood there empty-handed, or even those holding a dead pigeon. However, individuals who had previously handled dead crows (now with empty hands) were subjected to aggressive scolding by the crows for weeks.
8. They Attack Ravens
Crows and ravens belong to the same family and share similar characteristics, but they are far from friendly. Ravens are much larger and often pilfer crows’ eggs. Occasionally, they even prey on crows themselves. Despite this, the smaller crows are far from helpless victims.
A recent study analyzed over 2,000 reports from bird-watchers regarding interactions between crows and ravens in urban areas. The findings revealed that crows frequently teamed up to make life difficult for ravens.
Crow mobs are so aggressive that ravens avoid settling in prime locations that are home to such gangs. While other bird species use coordinated attacks to fend off larger predators, none do it quite like crows: 2–5 birds form a tightly-knit, organized unit.
This successful strategy is primarily attributed to the social nature of crows and the solitary behavior of ravens. Had ravens been more social and formed their own groups, the crows would have faced a much tougher challenge.
7. Aesop’s Fable Proved True
Ancient tales have long recognized the cleverness of crows. One such story from Aesop’s Fables, titled “The Crow and the Pitcher,” tells of a thirsty crow that, in search of water, encounters a tall jar. Realizing the water is out of reach, the bird cleverly drops pebbles into the jar to raise the water level.
Recently, researchers decided to put the fable to the test with a small twist. Instead of thirst, they enticed the crows with snacks. Two tubes filled with water and tasty treats were placed in front of the birds.
In front of the tubes were various objects the crows could drop in to raise the water level. Some were deceptive choices, like lightweight polystyrene pieces and hollow cubes that wouldn’t help at all. The other items included solid cubes and heavy rubber pieces.
The six New Caledonian crows quickly realized that the food was just out of their reach. Remarkably, they also understood the concept of water displacement and began dropping heavier objects into the container to raise the snacks to a reachable level.
6. They Consume Cane Toads
While it might seem typical for a crow to have a toad for lunch, this becomes far more surprising when the amphibian in question is Australia’s notorious cane toad. Originally introduced to the continent in 1935 to control a destructive beetle, the toad has now become a toxic invader. It secretes a lethal white substance that can kill dogs, cats, snakes, and even humans. Worse still, the toads thrived once they reached Australia.
A 2006 survey estimated there were approximately 200 million cane toads in Australia, their population thriving due to a lack of natural predators. In 2018, a photographer captured the first known evidence of crows filling the ecological gap. Within 40 minutes, one crow had eaten a cane toad and survived to tell the story.
Remarkably, it seems that Australian crows have figured out which parts of the cane toad are poisonous. They avoid the toxic white secretion by grabbing the toad by its limbs or head and flipping it onto its back to expose its belly. The crows then feast on the safe parts, such as the thighs, tongue, and intestines.
5. They Hold Grudges
Don’t anger a crow—it will remember. An unusual experiment demonstrated that crows do not forgive those who wrong them. A study conducted in 2012 revealed that researchers in Seattle conducted a strange “kidnapping” of several crows.
Wearing a mask labeled “the threatening face,” the researchers captured 12 crows from the wild. The birds were kept for four weeks, cared for by someone wearing a different mask, known as “the caring face.” Neither mask appeared particularly friendly nor frightening. Both were neutral, though distinct.
Despite this, the crows associated the experience with the masks. During their captivity, the crows were occasionally exposed to the “threatening face” before undergoing brain scans. This study marked the first time researchers observed that crows store negative associations in their brains in a manner similar to mammals.
Eventually, the crows were set free. A follow-up study revealed just how deep a crow’s inability to forgive goes. Despite the passage of years, the crows quickly recognized a researcher wearing the "threatening" mask. They mocked him and even performed several dive-bombing attacks.
4. Corpse Canoodling
Certain crows display deviant behavior—they have been known to attempt mating with the dead. In 2015, researchers conducted an extensive study in Washington State, using a stuffed bird to draw the crows in and observe their reactions. To their surprise, one crow tried to mate with the decoy, an act that could potentially expose the bird to disease or even predators. This was an odd behavior, especially considering the crows’ high intelligence.
To gauge how prevalent this behavior was, the researchers engaged with 308 pairs of wild, mated crows. They presented taxidermied crows, squirrels, and pigeons. The inclusion of other species helped determine if the crows’ necrophilic tendencies extended to corpses of animals other than crows.
The behavior was uncommon. Only about 4 percent of the crows exhibited a desire for romance with the deceased. They only attempted to mount the stuffed crows, making it clear that most crows shared the researchers' sentiments—canoodling with corpses was a hazardous pursuit.
The necrophilic crows also exhibited increased aggression, suggesting that the stress of the breeding season, coupled with the unsettling sight of a dead crow, may have caused them to become confused and irritable.
3. They Build Compound Tools
In 2018, a group of New Caledonian crows shocked researchers with their remarkable behavior. They demonstrated an ability once thought to be exclusive to primates: they crafted compound tools to access a snack hidden inside a box.
The discovery of this skill in birds is extraordinary. What makes it even more impressive is that the crows had no prior training, except for understanding the purpose of the box. They had to use a long object to retrieve the snack, showing remarkable problem-solving abilities.
Once they figured it out, the crows were left with pieces that were too short to reach the food individually. The solution was to combine them. Faced with the challenge, the crows managed to assemble the parts within 4 to 6 minutes after the experiment began.
After putting it together, the crows used the long tool to push the treat toward an opening in the box. This achievement required not only persistence and dexterity but also foresight. To combine the pieces, the crows had to visualize how everything would fit together before actually assembling it.
2. Crow Versus Eagle
In 2015, photographer Phoo Chan captured stunning images of an eagle and a crow in the California sky. In an unlikely showdown, the crow bravely decided to confront the larger predator alone. Chan’s photos followed the dramatic sequence, showcasing the crow’s bold attack and how it managed to latch onto the eagle.
For some reason, the crow decided to perch on the eagle's back. It gets stranger. The eagle didn't seem to mind its unexpected passenger. When bird experts examined the photos, they didn’t find the crow’s action of attacking the eagle strange. In the summer, crows can be particularly territorial, especially about airspace. Their young are vulnerable, which makes the adults more aggressive toward intruders.
Despite that, it's rare for a single crow to challenge a giant eagle and then settle on its back. So why was the eagle so unconcerned? Eagles face frequent harassment in the air from other species, so one more attack doesn’t seem out of the ordinary. Once the crow landed and became passive, the eagle likely ignored it, assuming no threat.
1. They Visually Judge Weight
Humans can typically judge the weight of a moving object, like how a fluttering leaf shows its lightness. This ability was once thought to be unique to humans, but crows have proven otherwise. Specifically, a study involving 12 New Caledonian crows, divided into two groups of six, revealed that they too can assess weight based on visual cues.
The training followed the same pattern for both groups: place an object in a box and earn a treat. However, one group received rewards only when they placed heavy items in the box, while the other earned goodies for depositing lighter objects.
In the second phase of the study, the crows were introduced to two unfamiliar objects. For three days, they watched as the suspended items reacted to a fan.
As expected, the lighter object moved more. The crows also observed the objects when the fan was off, and there was no movement. When given the chance to choose between the objects, depending on their earlier training, the crows picked the correct object 73 percent of the time.
