Five things about crows

Frankly, it's amazing that it's taken me so long to write about them

I’ll let you into a secret. Some of my friends call me Crow Jo. One just calls me The Crow. I like it. It’s the consequence of spending four years researching crows for my DPhil (now more years ago than I care to think about), meaning that these fantastic birds have become part of my identity. Four years of crows, that’s all, but the moniker has stuck and I’m happy with that, because crows will always hold a special place in both my heart and my brain.

[No, not that crow - although do I wish I had a pet crow that would ride on my shoulder and help me to avenge my enemies? Yes, yes I do.]

Since finishing my DPhil, I moved away from doing science to writing about it. And, naturally, the crows have come with me, in that I’ve managed to keep writing about them and spreading word of their amazing behaviour. I wrote about the way that corvid studies (corvid being the scientific name for the crow family) have contributed to the history of animal behaviour research in Ten Thousand Birds and, of course, the whole inspiration for Aesop’s Animals was the fable of The Crow and the Pitcher. In that book, I also tried to offer alternative, more biologically realistic, animal characters for several of Aesop’s fables, such as The Wolf in Sheep’s Clothing, and it just so happens that certain corvids were candidates for a couple of these too. You could say I’m on a mission to ‘corvidify’ everything, but in reality it’s just that the more we discover about these birds the more we learn how fascinatingly complex they are. Having said that, I heeded John’s advice about not making every chapter of Aesop’s Animals about crows; I suppose there’s a (theoretical) possibility that not everybody wants to hear about them all of the time.

Given the title of this post, however, today is not a day to be skimping on crow content! And hopefully, unless you’re in a hurry and misread crow for cow (it’s been known - my apologies if you were hoping for some juicy bovine-related content), that is exactly why you’re here.

The things is, as a bona fide crow nerd, I often forget that other (whispers, ‘more normal’) people haven’t dedicated as much of their brains to thinking about these birds as me. I assume that what I think are well-known facts are known by all, meaning that it can be a surprise when I talk to somebody who doesn’t know them. And so, in my overarching mission to keep spreading the word of the crow, I thought I’d do a corvid piece this week. It’s not supposed to be a feature-type piece telling a comprehensive story and summarising all of the evidence. Instead, I want to share some of my experiences from working with these birds, as well as shine a light on the aspects of crow biology that I find are often not appreciated or well understood. I was going to call it ‘Ten things you didn’t know…’ but apparently that’s not the done thing anymore; facts should come in lists of odd, unpredictable numbers like nine or thirteen or seven. I plumped for five, as ten is really far too many and I’d always prefer to leave you wanting more. So, as a kind of introduction to the world of crows, here are my five things that I think you should know.

1. They aren’t all black

We tend to think of corvids as big, glossy, black birds. It’s pretty much a defining characteristic - ask somebody to draw a crow or a raven and I’ll bet that all of them will colour it black. And while it’s true that many species are dressed in black (or black and white), that’s not representative of the whole family. Crows, ravens, jackdaws and the single rook are ‘true’ crows, in that they belong to the Corvus genus, but Corvus is only one genus within the family group Corvidae. Magpies, for example, are corvids but the genus is Pica (because they were thought to eat almost anything), while Blue Jays are Cyanocitta (blue chatterer), nutcrackers are Nucifraga (literally, nut breaker), and the Eurasian Jay is Garrulus (excessively talkative). There are others, including Pinyon Jays, Gray Jays, choughs and treepies, all of which are also corvids.

The true crows are monochrome at best, so don’t look to them for carnival clothing. The jays and magpies, on the other hand, sport some of the most beautiful plumage. Even here in the UK, a country notable for its distinct lack of colourful birds, we have the Eurasian Jay, whose dapper black moustache, rich chestnut plumage, and cerulean wing edges are a visual treat. Then, in North America, the Blue Jay is a gorgeous bird, while further south, the Green Jay is a tropical stunner. And on the other side of the world, the Green Magpie dazzles in acid apple green.

Left to right: Eurasian Jay (Nadine Trief from Pixabay), Blue Jay (PublicDomainImages from Pixabay), Green Jay (Hector Avila from Pexels) and Green Magpie (Image by Kevin from Pixabay)

One can only speculate whether the ways that crows and ravens have been portrayed in western cultures might have been different, had they been as pretty as some of these birds.

2. They are songbirds

Yes, naysayer, you’re right. Crows don’t sing. Crows caw, while ravens cronk, jackdaws tchak, and jays screech; it’s a fantastic medley of sound, but quite different from the melodious whistles and warbles of the more familiar songsters. You are therefore forgiven for thinking that they cannot be songbirds, for surely that must be a defining feature of this group?

Not so. Corvids, along with your familiar garden songbirds, are members of a group called the oscines, which are characterised by having highly developed vocal organs. Ravens are therefore the largest songbird. And while they don’t produce a song like a thrush or warbler, they do have a far more diverse vocal repertoire than just the obvious calls. Breeding pairs, for example, make a range of soft little noises to each other, and crows, ravens, jays and more are fantastic imitators of sounds in their environments. In the wild, they typically mimic birds of prey - Eurasian Jays have been captured on several occasions mimicking the mewing calls of buzzards, while in the US, Steller’s Jays are known to mimic the call of the Red-shouldered Hawk. Why do they do this? Because it provides them the opportunity to be deceptive. Steller’s Jays have been filmed emitting hawk calls around busy bird tables, which has the effect of sending all the smaller songbirds dashing for cover. The jay then gets the bird table’s goodies all to itself - a private dining experience for a clever bird.

In captivity, their tendency to imitate means they produce the sound most frequently heard - that of people talking to them. You just have to scan YouTube for videos of ravens saying ‘hello’ or, in the case of this White-necked Raven at Knaresborough Castle in Yorkshire, ‘Y’aright love?’ to see how common this is.

The video below shows Mischief, also a White-necked Raven, who is a superstar when it comes to producing human speech but, as the video shows, doesn’t always get it right.

I could honestly link to videos of ravens and jays imitating voices and birds and cats all day, but that would make this piece ridiculously long. So, just to say that if you still haven’t heard enough, here is a ten-minute video of a captive-born raven called Fable, chattering and singing away to herself in her aviary. It’s a joy to watch, and she only slipped in one cheeky little swear!

3. They recognise us (and hold a grudge)

You may have heard of the infamous study of American Crows conducted by John Marzluff and team on the Seattle campus of the University of Washington. Intrigued by anecdotal reports of crows and ravens recognising the faces of researchers who captured them, Marzluff set out to test it. In 2006, he and his students donned latex caveman masks and trapped seven crows around campus. When they later returned to the same spots, either wearing no mask or a Dick Cheney mask, the crows paid no attention. When, however, somebody returned with the caveman mask on, all hell broke loose! Marzluff has described how gangs of the birds would follow and divebomb them - they clearly recognised the face of their previous captor and weren’t happy about it. Here’s a photo of the caveman mask, taken from an Audubon article on Marzluff and his work, which is well worth a read if you’re interested in learning more.

One of the caveman masks. Creepy.

I followed up with Marzluff while I was researching Aesop’s Animals, and was intrigued to hear that he has been testing the birds ever since. In April 2020, 14 years after the initial capture, six of the 25 birds he encountered in the caveman mask scolded him and, astonishingly, so too did 12 of 27 crows he encountered wearing the Dick Cheney mask. As he told me: ‘I think what is going on with Cheney is that there is some generalisation of masked people being dangerous.’ Given that Dick Cheney shouldn’t be associated with danger (to crows), this indicates that the fear responses to people wearing caveman masks had spread. What’s more, since only seven birds were originally trapped, those fear responses had spread to birds that had never even experienced the unpleasantness of being caught. And, fourteen years on, only one of the original seven was still around. It remains to be seen whether the birds are still responding, but it’s possible that some of the crows on the Seattle campus will continue to scold mask-wearers because that’s just what they’ve grown up to do, without any direct experience of why.

The facial recognition research is infamous, but what’s less well known is that crows recognise us in other ways, too. Hand-reared Carrion Crows pay more attention when they hear the voices of unfamiliar people compared with the voices of their owners, which makes sense since unfamiliar people may be dangerous. But the category of ‘familiar’ and ‘unfamiliar’ is also broader than individual voices. Large-billed Crows in Japan paid more attention to the voices of strangers speaking Dutch compared with strangers speaking Japanese, showing that they can discriminate between other features of the voices that they hear. Novelty could mean danger for crows, so while they’re quick to adapt to things that go on in their environments, they’re always on high alert.

4. They can make and use tools

It used to be the case that chimpanzees were the only non-human animal known to make and use tools, and even that was a seismic discovery, sending shockwaves through a societal belief that only Man was capable of such things. Today, we know that many more animals incorporate tools into their lives, not least the New Caledonian Crow, which happens to be the species I studied for my DPhil in Oxford.

I’m not going to summarise the wealth of experimental research that has been carried out by different research groups on New Caledonian Crows since the 1990s, when their natural tool use was first scientifically investigated. Suffice to say, it shows these birds to be exceptional. All members of the species routinely use and make tools from twigs or strips of thick leaf; they are flexible in the way that they use and make them; and they can use them creatively to solve problems. In all of this, these birds rival chimpanzees, leading to the nickname ‘feathered apes.’

They also, if you keep them in captivity, have a habit of poking things into places you might not expect. They prodded sticks under doors, lodged little pieces of woodchip into keyholes and, most alarmingly, poked twigs at uncovered plug sockets (thankfully, they never had access to metal tools). They also used sticks to poke at things they weren’t sure about, such as a spider motif on somebody’s clothing, which was the inspiration for one of my studies on non-food related tool use. Indeed, just as you or I might do upon coming across something unknown or unpleasant in the woods, some of the crows used sticks to tentatively prod at rubber snakes and spiders put into their aviaries.

My biggest finding was that New Caledonian Crows will use sequences of tools. In essence, I presented them with a piece of food that was too far away to reach, a short tool that also could not reach the food, and longer tools that were also out of reach of their beaks. The way to solve the problem was to pick up the short tool and use it to retrieve another tool, which could then be used to retrieve the food. It sounds simple, but using a tool to get another tool is not something crows would naturally do (if a tool doesn’t reach in the forest, they just find another one); this was a test of their cognitive flexibility and planning behaviour. And they passed, some of them on their very first trial, when they couldn’t have learned through trial and error. One bird, Betty (the same bird that bent wire into a hook in a famous study a couple of years earlier), even solved the most complex problem, using a sequence of three tools in the correct order to reach the food. Here’s what that looked like, and the full publication with links to the videos is here.

5. They aren’t ‘stuck in time’

Unlike my cat, Hattie, who was the subject of my first ever Substack post, some species of corvid have been documented to show complex forms of memory and plan for the future (something called ‘mental time travel’ by some researchers).

My cat has no time for resolutions

Mental time travel means being able to re-experience times that have passed and pre-experience what the future may hold. We do this all the time, sometimes to detrimental levels, and that’s why practitioners of mindfulness urge us to be ‘more present’. Animals, it was long assumed, are essentially ‘stuck in time’. With no thoughts for past or present, they can therefore be thought of as the true masters of mindfulness.

Of course, claims of human superiority (‘humaniqueness’) rarely last long, and some of the most compelling evidence comes from corvids. There’s also great evidence from studies of apes, and even cuttlefish, among others.

Although Common Ravens have been observed planning for future tasks by storing tools, even with delays of up to seventeen hours, it’s the Western Scrub Jay that I want to discuss. These, like many corvids, store excess food in autumn, and clever experiments from the lab of Nicky Clayton in Cambridge have shown that they remember not just what they stored, but where and when - all the components of the subjective, unique memory experiences that we call ‘episodic’. In the absence of being able to ask the birds whether they’re re-experiencing the memory of storing food, this is the best that animal researchers can get. Not only that, but these jays seem to reflect upon their own experiences during the process of storing their food. Rates of theft are high, and to combat this a bird that is stashing its seeds may try to hide them out of sight of another bird, or even to make false stores. Squirrels do the same. But what’s really interesting about the jays is that they seem to make use of their own experience of thieving to inform their food caching behaviour. When birds that have previous form as thieves were being watched by another bird, they moved their food to new sites and tried to store it out of sight of the watcher. Naïve birds, on the other hand, didn’t. Scrub jays seem to relate their prior behaviour to the possibility of future stealing by another bird, which is remarkable.

In the other direction, Western Scrub Jays also seem capable of thinking ahead. In one beautifully simple experiment, the birds were given the opportunity to plan for breakfast, by allowing them to store pine nuts in locations that they learned would either contain or not contain food the following morning, and into which they might be shut into. If the birds were only behaving according to how they were feeling at the time of storing, you would expect them to store the nuts randomly. If, on the other hand, they were thinking ahead they should preferentially choose to store food in locations where there would be none, in case that’s where they ended up. This is exactly what was found, suggesting that the birds were intentionally pre-empting the risk of going hungry the next morning.

So there you go. There are many, many more things about corvids that I could write about - this really only scratches the surface. But since writing about them is one of my favourite things, it seems likely that I might follow this up at some point for a part 2. In the meantime, next time you salute Mr Magpie, have a think about what might be going on behind those beady eyes.

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Some interesting things

• A study was published this week about a male orangutan who tended to a facial wound with chewed up liana leaves, a plant which is known to have anti-inflammatory and pain-relieving properties. So called self-medication behaviour has been observed before, but not with anything that actually has medicinal properties. The authors conclude that, ‘This possibly innovative behavior presents the first systematically documented case of active wound treatment with a plant species know to contain biologically active substances by a wild animal and provides new insights into the origins of human wound care.’ Study here.

• Regular readers may remember Charlotte, the pregnant-by-parthenogenesis stingray at an aquarium in Charlottesville, who was touted to give birth ‘imminently’ back when her pregnancy was announced in February. I’m afraid I took my eye off the ball a bit in my last couple of posts, having provided regular updates on her before that. So it falls to me to let you know that Charlotte… HAS STILL NOT GIVEN BIRTH. And this now has my full attention, because Charlotte has her own fan club and some people are starting to call BS and question whether the whole thing has been a hoax to get attention. Said one user, ‘We've been catfished by a stingray.’ I prefer to believe that it’s just an unusually long pregnancy, given the unusual conception, because there are far too many conspiracy theories in the world already. But I shall continue to provide updates on this fishy story.

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#NaturePhotoADay

If you follow me on Instagram, you’ll see that late on New Year’s Day I decided to set myself the challenge of starting a nature related Project365 (this year, #Project366), meaning I have committed to sharing one nature photo every day for the whole of 2024. You can follow along on Instagram if you like, but I share my favourite from the previous fortnight here anyway.

This week there has been a mating frenzy around the bee hotels, with more bees emerging than I think we’ve ever had. I’ve shared some videos, along with photos from a wonderful long weekend in the Lake District, where we walked up hills, saw baby Herdies, caught up with friends and drank beer in the sun(!). The last fortnight also saw us in the local woods at the peak of bluebell time - the delicately scented blanket of blue was a real sensory treat.

But my favourite was finding this owl pellet. Natural treasure! These always bring back fond memories of collecting and dissecting them as a child, teasing apart the matted fur and trying to work out what had been eaten. This one was jam-packed with rodent bones, although I couldn’t tell you what. See what you can spot!

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