Occasional paper: The Suplex Bird

Today I’d like to talk about that delightful little companion of field and garden: the shrike.

[copyright Rosemary Mosco, 2024, birdandmoon.com]

If you know, you know.  And if you don’t know… well, let’s talk about shrikes.

Shrikes are a group of birds found across the tropics and the northern hemisphere.  There are about 30 species, which means they’re a reasonably successful group.  They’re a sister clade to the Corvidae — the crows, jays, and ravens — and like their corvid cousins, they’re pretty bright.  Today’s paper is about loggerhead shrikes, which is the little guy in the cartoon above.  (The cartoon is very accurate; Ms. Mosco takes her bird art seriously).  But it applies generally to most species of shrike.

So let’s go to the obvious bit first: shrikes are sometimes known as “butcher birds”.  This is because of their strange and rather gruesome habit of impaling their prey on thorns or sharp branch-ends.


Shrikes of all species and both genders do this, because it’s a way to store food safely.  (It’s basically the same strategy that a leopard uses when it stashes a dead antelope ten meters up in a tree.)  However, in several species the male shrikes take it further and will decorate a particular bush or tree with dozens of little corpses — mice, large insects, small birds — as a display to impress and attract females.

Okay, that’s strange and interesting.  But while it’s the thing most people know about shrikes, it’s far from the strangest thing about them.  Shrikes are much weirder than people realize.

Let’s start with something so obvious it gets overlooked.  Look at those photos.  The shrike is a predator, right?  It’s a pure carnivore, eating nothing but meat and flesh.  Its entire diet is large insects and small vertebrates: mice, frogs, lizards, snakes, and other birds.

What do we expect a predatory bird to look like? Well, normally we expect it to look something like these guys:



Okay, those are big and shrikes are small.  So, what do we expect a small predatory bird to look like?


Despite their differences, these guys are all very obviously birds of prey.  They all have hooked beaks for tearing flesh, forward-facing eyes, and — this is key — they all have large, powerful talons.  And those talons are absolutely crucial!  They use those sharp, strong claws for gripping, for killing, and for dismembering their prey.

Now look at the shrike.  It has a slightly hooked beak, its eyes are only somewhat forward-facing, and it has no talons whatsoever.  It’s hopping around on pretty ordinary little bird feet, not much different from a common thrush or sparrow.

Okay so:  why doesn’t it have talons?  And without talons, how does it manage to capture, kill and dismember its prey?

Well, the shrike has evolved its own, very strange mode of predation.  It’s not a pursuit predator, like a wolf; nor an ambush predator, like an owl or a cat; nor even a speed predator, like a hawk or a cheetah. No.  The shrike is a deceit predator, and it uses a strategy that is completely unique among birds.

Let’s start with its appearance.  The shrike looks like a harmless songbird.  In fact, it looks like what birders call a “Little Brown Job” — meaning, one of the dozens of species of small-to-medium-sized brownish or greyish songbirds without much color or any distinguishing characteristics.

[all images public domain]

Can you spot the killer in this lineup?

— And here’s a thing: the shrike is, in fact, a songbird.  It’s not related to hawks or falcons at all.  Its remote ancestor was probably something like a small jay or magpie.  But while other songbirds evolved to hop around and eat seeds and little bugs and whatnot, the shrike went a different route.

Because, you see, the world is full of Little Brown Jobs.  Sparrows and chickadees, thrushes and tits, flycatchers and warblers and wrens: they’re all small, they’re mostly spotted or striped white and grey and brown, and they’re all harmless to anything larger than a beetle.  So animals of all sorts — frogs and mice, small snakes and lizards, newts and shrews and of course other birds — have evolved to ignore Little Brown Jobs. 

Because if you’re a mouse or a lizard or a sparrow or some other small prey animal?   And you freak out every time a harmless chickadee or nuthatch comes near?  You’re going to quickly die of sheer stress, because Little Brown Jobs are everywhere.  You can’t be fleeing for cover at every pipit or junco.  You have to do threat assessments.  You have to filter.

And that cognitive-perceptive filter is where the shrike makes its living.  It has evolved to look just enough like a harmless songbird that it doesn’t trigger any avoidance reflexes in potential prey. 

But this introduces some problems.  As we all know, one of the triggers for prey is the distinctive silhouette of a raptor.  That’s why those hawk-shadow cutouts work to warn birds away from glass, and it’s why a fake owl makes a great scarecrow.



But another trigger is… talons.  Studies have shown that a bunch of different prey species will flee or hide in the presence of a bird that has talons. 

So the shrike doesn’t have talons because it can’t.  Talons would completely blow its cover.  But without talons, how then does the shrike kill its prey?  

Put a pin in that, because there’s one more freaky thing about the shrike.

“She will stand at perch upon some tree or poste, and there make an exceedingly lamentable crye and exclamation…all to make other fowles to thinke that she is very much distressed and stands in need of ayde; whereupon the credulous sellie birds do flocke together at her call. If any happen to approach neare her, she…ceazeth on them, and devoureth them (ungrateful subtill fowle) in requital for their simplicity…”

— That’s from The Boke of St. Albans, a 15th century treatise on hunting and falconry.  And it describes the shrike using what scientists call an “acoustic lure”.  

Because shrikes don’t just look like songbirds.  They sound like them, because they mimic their calls.  The shrike’s default call is a harsh little shriek, like a jay’s call but higher pitched.  (Hence the name.  Shriek, shrike.)  But they’re not restricted to that call, because they’re also excellent mimics.  And they will very deliberately mimic other birds in order to lure them close.  They start with distress calls, presumably because those are easiest.  But older and more experienced shrikes can expand their repertoire to include territorial challenges and mating calls.  

When I described this to an academic friend, he cried out “It’s a monster from folklore!”   And it kind of is, right?  The voice from the forest that calls out for help, or that sings a song that’s seductive and sweet?  But don’t you go there… Yes, if sparrows could talk, the shrike would be their Dracula, their Grendel.

Acoustic luring is rare among land vertebrates, but it’s not unknown.  Most famously there’s the margay, a South American jungle cat, that can mimic the distress calls of baby monkeys.

The shrike’s cousin, the jay, also mimics the calls of hawks — though apparently it does this, not as an acoustic lure, but defensively, to protect its territory and drive away competitors.  Jays have been observed using hawk calls to clear a bird feeder for themselves.

But okay: the shrike gets close to prey by looking harmless and sounding harmless, and it can even lure other birds with fake calls.  But now that it’s up close… with a relatively small beak and no talons, how does it actually kill its prey?

Well, we used to think we knew.  Let’s look again at our little friend:


[Neighbors said he was quiet and kept to himself]

It doesn’t have talons.  And it doesn’t have a massive beak like a hawk or an eagle, either.  But its beak does have that little overhanging “tooth” at the end. And its head is rather big for its body, and its neck is quite thick.  From a certain angle, it almost looks a bit hunchbacked.  What’s going on with that?

Well, what we saw was that the shrike would often begin its attack with a sudden sharp peck, always delivered to the prey’s head or neck.  So it was assumed that this was the killing blow, presumably severing the spinal cord.  The shrike would then grab the prey, give it a shake, and fly off.  When vertebrate prey items were examined post-mortem, sure enough, the spine was severed.  

(By the way: the impaling on thorns?  This is how shrikes dismember their prey without talons.  They evolved to use a tool, the thorn, as a utensil.  Using it as a larder, and then as a sexual display, presumably evolved later.)

Okay so that seemed to make sense, except… even with disguise and luring, killing your prey with a single very precise blow seems like kind of a tall order.  Also, while the shrike’s beak is sharp and strong, it didn’t seem quite the right shape for a deep severing blow.  And further, while the shrike would often start with the peck, sometimes it would skip it and go straight to grabbing and shaking.

Which brings us at last to the paper.  These guys captured shrikes, gave them various prey items, and then took video of the attacks.  And what they discovered was: the peck is not the killing blow.  The peck, a sharp strike to the head or the back of the neck, is just the setup.  It’s done to stun and disorient the victim, just for a second or two.  But it’s not what kills the prey.

What kills the prey is the shaking.  The shrike’s strong, hooked beak isn’t designed to kill with a blow.  It’s designed to stun with a blow, and then to clamp down strongly on the prey’s neck while the shrike shakes it.  The shrike’s thick neck?  Is because the shrike has massively powerful neck muscles.  The shaking can deliver sudden accelerations of up to six gravities in a fraction of a second, which is roughly like having a 50 pound weight quite suddenly dropped on your neck from a yard up.  It’s the shaking, not the peck, that severs the prey’s spinal cord.  The shrike suplexes its prey to death.


[yes strictly speaking this is a rear naked choke not any kind of suplex, don’t @ me.]


What triggered this post: I saw a shrike in our garden recently.  And it was shaking a prey item — a small snake, I think — and also slamming it against a tree.  (They do that, too.)

Like a lot of carnivores, shrikes are fiercely territorial.  So if our garden is part of its territory, it’s probably been around for a while.  But I never noticed it.  Until I saw it in the actual act of killing, my brain just processed it as another nondescript small dull-colored songbird, not very interesting.  

And it’s not just me.  If you live in the northern hemisphere, and not in a large city, you’ve almost certainly  seen a shrike.  They’re not particularly rare!  But you probably didn’t notice it, because not being noticed is exactly their thing.

Anyway.  Shrikes can live a decade or more, getting more experienced and more cunning all the time, harder to spot yet also more convincing in their mimicry and lure.  (“Like a Master Vampire!” said my academic friend.)  So good chance that little guy is still out there, hopping around, looking and acting and sounding like a harmless little songbird… until.



I hope so.