The more we learn about crows, the smarter they get!

A  few years back, I wrote an article for Washingtonian magazine about wildlife to be found in urban areas, even a large metropolis like Washington, DC. In it, I made a casual reference to the “smart crow” scavenging for food in a McDonald’s parking lot. I couldn’t believe it when the editor omitted the word “smart” in the published article – maybe he thought readers would get confused, thinking I meant smart like Albert Einstein!  I guess I shouldn’t have assumed that everyone had heard of the intelligence of the corvid family, which includes crows, ravens, rooks, jays, jackdaws, and magpies.

Always watching and learning, crows are very resourceful. They can mimic calls of other birds, make tools, play tricks on each other, recognize and communicate danger to flock mates, and talk to each other in a dialect all their own. Their personality and ingenuity make them a fascinating group to watch. In all animal groups, brain size increases with body weight. The corvid’s brain is larger than other birds relative to its size – more in line with primates – when graphed against its body mass. This undoubtedly figures into what many researchers consider the bird’s intelligence in getting along in the world.

Most of the year, crows travel in tightly-knit family groups where they work cooperatively to find and exploit food sources. Photo by Lisa Rest at musicbirdblog.com.

Most of the year, crows travel in tightly-knit family groups where they work cooperatively to find and exploit food resources. Photo by Lisa Rest at musicbirdblog.com

Generally too cautious to come to feeders, crows will often congregate in large numbers to glean farm fields, but they have also developed some pretty unique ways to get food. My husband and I took a picnic lunch up to the Blue Ridge Parkway one day and while we were eating, we watched two crows dropping walnuts onto the hard road surface to crack them open. Then they would fly down to inspect the shells and clean out the nut meats. I’ve heard that crows will also place hard-to-crack nuts on roads in front of passing vehicles and then retrieve the crushed pieces. Maybe someone else has witnessed this, but I haven’t.

Some crows are known to be tool users in their natural environment. The New Caledonian Crow has been intensively studied recently because of its unique ability to manufacture and use its own tools in the day-to-day search for food. These tools include breaking off twigs and using torn leaves with barbed edges as hook-tools to dislodge insects from holes and crevices.

Crow using a stick as a tool. Photo by sciencemag.com

Crow using a stick as a tool. Photo by sciencemag.com

Scientists from New Zealand’s University of Auckland wanted to find out if New Caledonian Crows could spontaneously make tools from materials not previously encountered in order to get food. Placed in a situation where the bird can reach but not obtain a morsel of food using a straight piece of wire, it will bend one end of the wire into a hook. It then uses the hooked end to reach and obtain the food. The researchers believe that there is cultural evolution going on with the New Caledonian crows; that is, they invent new tools, modify existing tools, and pass these innovations to other individuals in their group.

As a young girl, I watched and listened to the crows communicating with each other. I decided the “crow call” was the perfect way to secretly communicate with one of my tomboy friends. While playing in the abandoned orchard behind our neighborhood, the “caw-caw” let us “talk” in a language no one else could decipher. I felt very clever using our secret crow calls. We were, after all, being sly and trickster-ish, mimicking what we understood to be a very intelligent bird.

If only we’d known back then what would come to light about crow intelligence years later, we’d have reveled in our secret crow calls even more. There’s a lot more going on in the corvid brain than we ever could have imagined.

“The important thing is to not stop questioning. Curiosity has its own reason for existing.” ~ Albert Einstein

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Common Raven – an oxymoron?

Photo by Omar Runolfsson @Creative Commons

Photo by Omar Runolfsson @Flickr Creative Commons

My only up-close encounter with a raven was several years ago while hiking to the top of a mountain. Stopping to sit on a rock and rest, I looked over and saw one of these super-large black birds perched, not 20 feet away, on a limb jutting out over a cliff. From its high perch, the raven could see the Maury River and the surrounding valley below. We watched each other for several minutes, neither uttering a sound, until his curiosity was satisfied and he launched himself from his perch and soared out over the valley.

Even now, many years later, one of the greatest pleasures I get to experience living in the Blue Ridge is watching a raven flying overhead on easy, flowing wingbeats, filling the empty spaces of the valley with an echoing croak. Surveying its domain, from the Alleghenies to the west and the Blue Ridge to the east, and all the ridges and valleys in between, the raven is master of the skies.

Perhaps no bird is so widely recognized or enters our consciousness as permeated in legend or folklore as the Common Raven. Native Americans of the Northwest revere ravens as being the creator of earth, moon, sun, and stars, but also regard it a trickster and cheater. Poets and authors of Western cultures have used the raven to symbolize death and evil and portrayed them as harbingers of doom. Other than possibly the American Crow, no other bird is steeped in so much mystery, myth, and misinformation.

In reality, ravens are curious, playful, and clever. Thanks to the efforts of researchers and ornithologists, we now know a lot more about this secretive species, and one thing is certain – there is nothing common or ordinary about the Common Raven. Wonderful books have been written about ravens that give us new insight into their habits and social dynamics. Books such as Mind of the Raven: Investigations and Adventures with Wolf-Birds (Bernd Heinrich), Bird Brains: The Intelligence of Crows, Ravens, Magpies, and Jays (Candace Savage), and In the Company of Crows and Ravens (John M. Marzluff ) allow us to peek into the complex world of the raven.

Even the most devout bird watchers don’t often realize that the raven displays ability in problem solving, as well as other cognitive processes such as imitation and insight. One experiment designed to evaluate these processes involved a piece of meat attached to a string hanging from a perch. To reach the food, the bird needed to stand on the perch, pull the string up a little at a time, and step on the loops to gradually shorten the string. Four of the five Common Ravens used in the test succeeded. (source: Wikipedia.org)

Ravens also have a playful side that few of us will ever get to see because of their shyness around humans and preference for roosting and nesting in inaccessible areas. There are reports of them making their own “toys,” breaking off twigs to play with other ravens. Their play often involves inventive behaviors such as sliding down inclines on their belly, repeatedly dropping sticks while in flight then catching them in mid-air, hanging upside down by one or two feet, snow “bathing,” giving vocal monologues, and playing “tug-of-war” or “king-of-the-hill” with other ravens. (source: Cornell Lab of Ornithology).

Last week I noticed two ravens flying overhead that were engaged in behavior I hadn’t seen before. One bird bumped into the other bird, which fell off to the side, then returned to bump the first bird. It went back and forth like this, the two birds jostling each other until they were out of sight. At first I thought it was a raven chasing an intruder out of its territory, but usually such altercations are over rather quickly. I now believe the two birds were a mated pair or family members just having fun doing what ravens do.

Ravens, like their crow cousins, have a reputation for being noisy. In fact, I usually hear their raucous calls before I see them when they leave their roosts in the morning and fly out over the valley in search of food. Most times, I see only one raven, but if flying with a mate, the pair will exchange calls back and forth while hunting.

National Park Service photo

Ravens always seem to have a lot to say. – National Park Service photo

Common Ravens have the greatest variety of calls than perhaps any other animal in the world except human beings. Most of the 30 categories of vocalization recorded are used between pairs and their offspring and include alarm calls, chase calls, and flight calls. Non-vocal sounds include wing whistles and bill snapping. If one of the pair is lost, its mate reproduces the calls of its lost partner to encourage its return. They can mimic other birds, and when raised in captivity can even be taught words. (source: Cornell Lab of Ornithology)

It seems an unfortunate injustice indeed to choose the word “common” to identify such an extraordinary creature as the unCommon Raven.

Wisdom begins with putting the right name on a thing.
(Old Chinese Proverb)