POSSESSING LARGE BRAINS for their body size, a knack for social networking that requires no internet connection, and keen powers of observation, crows and ravens are among the big personalities of the bird world. They are also what ornithologist Dr. John Marzluff calls, “black-feathered practitioners of lifelong learning,” and from him we can learn about the capacity of their avian brains and the range of things it allows them to do–from the funny to the daring, much of it almost unbelievable.
Marzluff is a renowned ornithologist and urban ecologist, and professor of wildlife sciences at the University of Washington. He is author most recently of “Welcome to Subirdia”—his fifth book. He has written other titles specifically about his area of particular expertise, the corvids—crows, ravens, jays and their relatives—including one in collaboration with illustrator Tony Angell that I just read called “Gifts of the Crow,” the subject of our discussion.
Read along as you listen to the Dec. 21, 2015 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).
my crow and raven q&a with dr. john marzluff
Q. It has been raining here today. We haven’t had much rain in the Northeast lately, though I know you’ve been having crazy, crazy rain in the Pacific Northwest.
A. It is very, very wet.
Q. Looking out the window today, I was thinking: How do birds stay dry, anyway? There is always a question about the birds; I have infinite questions about them.
A. They’ve got, fortunately, very nice oil glands, and they just coat themselves with a sheen of oil and most of the rain just beads right off of their back and rolls off.
Q. Smart bird—or well-built birds.
The corvids—the crows, the ravens. I love these birds, and consider it a treat when a flock of crows come calling or a raven leaves its distinctive tracks in the snow.
I suppose I have to ask the boring question first: Who’s who? How do we tell crow and ravens apart?
A. The raven is a much bigger cousin of the crow. They’re in the same genus [Corvus], and so they are closely related and share a lot of characteristics because of that. But the voice is the easiest characteristic. If you can hear them, the crow is mainly going to caw, and the raven is going to quark, and drip like a faucet and bark like a dog, and make lots of other sorts of noises.
A. Being about twice the size, and having about a 4-foot wingspan, the raven really dwarfs the crow when you see them side by side. Its tail is also more shaped like a diamond, and it’s got more of a beard around its throat from its lanceolate feathers there.
Q. I feel like I see crows in numbers, and ravens in onesies and twosies. Is that an incorrect assumption, or a characteristic?
A. That’s quite characteristic. Ravens and crows both mate and form monogamous, lifelong pair bonds, but the raven quickly kicks its kid out of the territory and the pair patrols that territory. [Laughter.] You typically just see the pair.
Q. Is the raven our largest songbird?
A. It’s the largest songbird in the world. Technically it’s a songbird because of complex throat musculature that it has.
Q. It has a syrinx?
A. All birds have a syrinx. It has a junction box there between the two branches of the bronchi that go to the lungs, and it’s where the voice is produced. But the thing that the songbirds have that the others don’t are very complex muscles that wrap around that syrinx so that it can warp and pull and stretch in so many ways to make such a variable amount of noise.
Q. Interesting. The subheading of the book “Gifts of the Crow” reads, “How Perception, Emotion, and Thought Allow Smart Birds to Behave Like Humans.” A number of times as I was reading the book I was flashing on a National Geographic series from a few years ago called “Monkey Thieves” about the troupes of rhesus macaque monkeys of Jaipur, India, and thinking these corvids remind me of those monkeys! [Laughter.]
In fact in the book you do note several aspects of avian cognition seen in these birds that scientists had thought for a long time only humans and some monkeys possessed–like insight, for instance.
A. Insight has always been one of the hallmarks of primates. The idea here is that you can look at a problem and intuit the solution, basically see the steps that are required to solve this problem. So imagine food hanging from a string, or buried in a tube you cannot reach. You might start thinking, “How can I position that tube, or could I use a tool to get at that food that’s in there?”
Monkeys of course will solve that problem, but crows do as well. Depending on the species, some, like the New Caledonian crow would fashion a tool to get that food out—and they do it almost instantly when they see the problem.
Others might drop things into water to raise the level and float food up to them, or use other sorts of advanced techniques to get at the solution to a problem. [Above, New Caledonian crow making a hooked tool from straight piece of wire.]
Q. Amazing. You also say in the book that they can be observers of body language and the intent of other individuals, or other creatures.
A. We did some experiments here with our American crows that live here in Seattle, and they’re quite tame here. You can typically get quite close to them in the city. But if you lunge at them or even if you just look at them as you approach, they are a completely different bird. They’ll stand away, they’ll move away; they understand that you are paying them some attention and therefore it may be good or it may be bad, but they’re not going to take the risk.
Q. Until the 1960s, you write, birds were regarded as simpletons by scientists, like that expression “birdbrain.” You don’t think birdbrain is a slur, do you? [Above, another video example of birds’ ingenuity in using “tools.]
A. It’s a compliment of the highest order, to be sure.
Q. In some of the corvids, their brains are particularly large for their body size.
A. It’s important to understand that it is relative to their body size. The brain of a crow is about the size of your thumb, but the bird only weighs less than a pound. So it’s a large brain relative to its body size. Compare it to something like an ostrich—which is the other extreme for a bird. A very big body, but probably not the brightest bird out there. But crows and ravens, their brains are much more for their body size on line with what we would consider the small monkeys to have. They’re really more like a primate in terms of the amount of brainpower they can bring to a problem.
Q. Mammals and birds both trace back to same reptilian brain—we have a common ancestry, don’t we?
A. That’s the one point we try to make in the book. Some of the things you see and how you interpret them do seem fantastic. But it all comes back to the similarity we have in not only our brains, but the particular nerve cells in our brains—the transmitters that allow us to communicate between nerve cells in the brain and form complex memories. That all goes back to this reptilian heritage that mammals and reptiles and birds all share.
Q. So interesting. Did diet—or does diet—have to do with how developed certain of the corvids’ brains have become? Because they love food, don’t they? [Laughter.]
A. It’s involved, and they’ll do anything to get at food.
It’s almost to flip that around a bit: Because they have a large brain they also have to capture a lot of energy every day. So they have to have a high-quality diet, or at least a lot of whatever they’re eating.
The brain is the most expensive organ in the body for us as well as any other vertebrate. It takes a ton of energy, and when you have a big one, you’re sacrificing the need to do other things instead of getting food. You’re sacrificing that and trading it off with the ability to do things very efficiently with that brain.
Q. We’ve been talking about ravens, and crows, and they have other relatives like the jays. Do they have similar diets, or eat distinctive things?
A. They’re very different. I would say that within the corvids in general, and there are about 140 species there, some are extreme specialists. The pinyon jay, for example, eats primarily pine seeds. It stores pine seeds through to the fall to fuel its economy all winter and spring. Other birds like the raven and generalists, and they’ll eat anything that moves or lies around too long [laughter]—they’re going to eat it.
Some are very flexible in diet, and others are very specialized. The interesting thing is that specialization has driven some parts of the brain of these birds to be incredible—like the pinyon jay I mentioned has to remember where it puts all these seeds. So it has a very large hippocampus, part of its brain that’s responsible for spatial memory.
The raven has got to solve lots of different problems and figure lots of different foods out, so it has a large general forebrain.
Q. You write in “Gifts of the Crow” that everyone always has a crow story, and I suspect when you go to cocktail parties everybody wants to tell you theirs.
Q. [Laughter.] Rather than tell you that I wanted to ask about another corvid I seem to attract a lot, the blue jay—not an unusual bird in my rural spot. One of my peculiarities among many is that because nature always cleans its plate, I waste nothing—including mice from traps in the cellar or barn or shed. I just put them outside, and by the next morning someone takes it away.
The other day I tossed one out onto the lawn, and went inside, and within minutes something caught my eye, and it was a blue jay that came and stabbed at the mouse and pushed it around at it for a minute, then lifted off and left with it. I didn’t realize they were omnivores or carrion eaters.
A. I would say even the most specialized seed eaters—and the blue jay is toward that line, and specializes in acorns for the most part. But even those that are specialized in the corvids, they’ll always take matter like that. They’ll take a small mouse, a small bird, an egg, a small snake or frog. Again kind of getting back to your first point about the quality of the diet, and that’s high energy, high fat and protein that’s coming in with a small animal like that. That really helps them meet their energetic needs.
Q. Last winter I saw a first with the blue jays again, when they pecked light-colored latex paint off my front porch and would disappear with pieces of paint. And eggshells as well, which I put out for them—within moments, they pick them up and fly away with them. Do they have a crop where they can stash things, or a pouch?
A. The blue jay’s got what we call an expandable throat, which can hold a couple of acorns. When you get into something like the Clark’s nutcracker, they have a special pouch that’s a space under their tongue that opens up like a pelican’s pouch, and they can put 150 or so pine seeds in that thing and fly off with it.
So within the corvids you see these different adaptations to their different ways of life, and again the blue jay is more general—so it hasn’t committed all the way to a throat pouch, but it’s certainly got some elasticity there to help it carry a big load.
Q. The informal verb “rook”–meaning to take money from someone by fooling or cheating them—and it’s also the name for a species of corvid. No coincidence, correct?
A. I think it’s definitely related, yes. [Laughter.]
Q. There’s a chapter in the book called “Delinquency.” [Laughter.] Let’s talk about that a little.
A. The rook is a rather large corvid, sort of halfway between a raven and a crow in size that lives in northern Europe. It’s closely tied to agricultural lands. It probes around for worms, for the most part. But they are very keen on getting food and hiding it, and keeping it hidden from others. They try to deceive others in terms of where they put food for later use. I would guess that they probably stole things that were laying around the farm—not just plants, but shiny things as well. That might have led to that saying.
Q. As I mentioned, there’s a chapter in the book called “Delinquency,” and a wonderful anecdote about windshield wipers, and delinquent crows.
A. It’s not an isolated incident. The interesting thing is that evidently corvids have a little bit of a penchant for windshield wipers all around the world. Out here in the Northern Cascades, I got a call from the National Park Service that was concerned with campers there. They were having their windshield wipers stolen while they were hiking or sleeping, and they were afraid that people would have an accident if they got in their car and didn’t realize their wipers were gone and hit a rainy day like today.
They figured out that it was a raven that was stealing these windshield wipers [laughter], and they had no ideas why, or how many birds were involved. My daughter and I went up there to start catching the ravens and tagging them and seeing who was participating, and maybe figuring out why they were doing this.
Long story short: It was a pair of ravens that lived right around this visitor center that was the culprit, and the folks at the park had already named it Hitchcock, and they were concerned again with the damage it was doing.
We tried to use its big brain to our advantage, and we captured the bird, Hitchcock and its mate. We captured them in a parking lot where cars are vulnerable to having their windshield wipers taken, and we banded the bird right on a windshield.
A. That’s an uncomfortable thing for a raven. They’re being held by us. Typically we try to be as calm and keep the birds in the dark as much as possible, but we didn’t this time. We let him look full-on at the windshield the whole time we were putting a band on his leg and measuring him, and tagging him for our scientific use later. And then we let him go. But we hoped that he would form a complex memory of that bad thing—that guy holding me, and looking at a windshield wiper and being in this area—and stop messing with windshield wipers from then on.
And indeed the behavior declined. It doesn’t occur now at all, and those birds are still around. We’ve been able to utilize the birds’ intellect to teach it what’s not acceptable in this setting, and allow the bird to live there and keep other ravens that might pick up the habit from coming in as well.
The other alternative was just to kill the bird and remove it.
Q. And people do that; they get infuriated with birds and destroy them.
A. There are other solutions, and this was an example.
Q. You said the birds are still there. How long do crows and ravens live?
A. The longest on record are somewhere in the 15- or 20-year range, because you have to have a bird banded to follow it, and really know its exact age. If you do the calculations based on their annual rate of mortality, which is very low—less than 5 percent—certainly there are some birds out there that are 20, 30 or maybe even 40 years old out there in the wild.
Q. Wow. With the windshield-wiper kleptomania, you said it’s not just that one incident?
A. It’s been reported in several national parks in the West. It’s been reported in Australia with a different species there. For some reason, these birds really like rubber. Maybe the pliable nature is kind of like an animal skin, and they tug at it—and that’s something that they find possibly leading to food, or that they find interesting or stimulating to touch. We’re not really sure why they do it.
Q. I am always wowed by stories about crows’ ability for facial recognition. Can we talk about Dick Cheney for a minute? [Laughter.]
A. This is funny. It was an experiment we devised, because whenever we study the birds around here, we climb to their nests to band their babies. Or we’d catch them to band or tag them. We always felt that the birds knew us after that; they acted differently. Some were more aggressive; some were more cautious around us after we had watched them awhile.
So we tested that idea directly. The idea we had was to catch a few birds—and the way we catch them is by shooting a net over them. So that’s a scary situation again. When we ran up to get the birds out of the net to band them and tag them, we wore a particular mask.
In our case, the dangerous guy wore a caveman’s face. So the birds as they were having this difficult experience with us, they were looking at a caveman the entire time.
Our idea was then anybody could wear this caveman’s mask later, and walk through where we caught birds. We could see if these birds really respond differently, and it wasn’t just us thinking that. Because anybody could do it.
We also wanted to compare the reaction to us wearing a different mask—and that’s where the Dick Cheney comes in. [Laughter.]
Dick Cheney was the vice president at the time, so his mask was on sale in the internet, and I got a couple. We now walk around campus as Dick Cheney or the caveman, and see if the birds can tell us apart.
Q. And they can, yes?
A. And they can, and they have been for nine years now. So this is an example not just of fine discrimination—to tell those two apart—but also social learning. Birds that are able to tell those masks apart now weren’t even born when the caveman did anything wrong.
They’ve learned from seeing others who were around demonstrate that this guy is bad.
Q. Besides being gifted in these ways we’ve been talking about, crows are inclined to give gifts—you mentioned shiny objects earlier. Have you ever received any yourself?
A. Personally I have never gotten a gift from a crow, probably because I do more scary things to them than pleasant things to them. But I’ve been gifted by learning about these treasures that many people get, and I have seen many of these treasures—and I’ve seen video of the birds holding these things now.
What it looks like are fairly young birds probably, or perhaps birds that don’t have a mate that are courting a human in this case really as a social partner. Maybe a mate, but at least as a social partner.
They give things like trinkets from lockets, or necklaces or keys, or pencil erasers, or shiny rocks and pieces of glass are very common that people get. It happens where either someone’s done a crow a really good deed like free it from a trap, or where they have been feeding them consistently.
Q. I love it. I’m so glad you could join me again to tell us about the gifts of the crow.
(Black-and-white illustrations from “The Gifts of the Crow” are by co-author Tony Angell.)
more from john marzluff
- A Tedx talk (above video)
- On how crows regard their dead and learn from death, from a recent interview in “The New York Times”
- Our previous interview, on “Welcome to Subirdia” (about birds that thrive close to us)
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MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its seventh year in March 2016. In 2016, the show won three silver medals for excellence from the Garden Writers Association. It’s produced at Robin Hood Radio, the smallest NPR station in the nation. Listen locally in the Hudson Valley (NY)-Berkshires (MA)-Litchfield Hills (CT) Mondays at 8:30 AM Eastern, rerun at 8:30 Saturdays. Or play the Dec. 21, 2015 show using the player near the top of this transcript. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).
enter to win the book
I’LL BUY A COPY of “Gifts of the Crow” for a lucky reader. All you have to do to enter is answer this question in the comments box below, all the way at the very bottom of the page after the last reader comment:
What’s your crow (or raven) story? As we said in the interview, everyone seems to have one.
No answer, or feeling shy? Just say, “Count me in,” or something to that effect, and I will, but a reply is even better. I’ll pick a random winner after entries close at midnight Monday, December 28, 2015. Good luck to all. (Disclosure: Purchases from Amazon affiliate links yield a small commission.)