Necessity is the Mother of Invention, or, How to Eat Like a Shrike

Common Name: The Shrike

A.K.A.: Family Laniidae

Vital Stats:

• Family consists of three genera and around 30 species
• Shrikes range in size from 17cm (6.5”) up to 50cm (20”) long
• Feathers may be black and white, cream, grey, or brown

Found: Various species found in North America, Southern Africa, and Eurasia

It Does What?!

Sometimes a creature aspires to a spot a little higher on the food chain, but doesn’t quite have all the equipment to get there. Behold the shrike, the bird that wishes it were a raptor. Like birds of prey, shrikes have strong, hooked beaks, sharp eyes, and an appetite for meat, but they’re missing a couple of important features. First, and most important… no talons. Shrikes can’t grab a victim and tear it into pieces like a hawk or falcon could. And second, no crop (a sort of internal storage pouch), so they can’t eat a large quantity of meat in a single sitting.

Not to be deterred by their anatomical shortcomings, these inventive go-getters have come up with a single solution to both problems. Two birds with one stone, if you will. After dispatching their prey with a quick beak to the back of the neck, shrikes will carry the carcass to a nearby shrub and actually impale it on a short branch or thorn. Aside from looking incredibly badass, this serves to anchor the body in one place, allowing the shrike to use its beak to rip the meat into pieces. What’s more, the bird can just leave its leftovers hanging there for later, like the meat locker at a butcher shop. [Wondering what that looks like? Here’s a video, set to appropriately ominous music.]

What kind of prey are we talking about here? Anything from small insects right up to mice, frogs, lizards, and other birds. There’s even a record of one killing and impaling a good-sized bat. Impressively, shrikes have also hit on the value of ageing their food – one species hunts the toxic lubber grasshopper of the southern United States. The dead grasshoppers are then left hanging for several days to let the poison degrade before being eaten. Clever birds.

Shrikes are monogamous and share in parenting duties; when the female is sitting on eggs, it’s the male’s job to go out and kill something nutritious for two. Of course, this makes selecting a good hunter an important task for females during mate selection. When a single male wants to advertise his skills, he makes a conspicuous display of his biggest, most impressive kills for any prospective ladies. Once he’s gotten one’s attention, he performs a mating dance that mimics the action of impaling prey on branches and then feeds her from his assortment of carcasses. (Be sure to include this point next time you’re explaining ‘the birds and the bees’ to someone.)

I guess when you have only one major skill, you want to make the most of it, because aside from eating and attracting mates, shrikes also use their impaling trick for communication. Bonded pairs are territorial and will defend their terrain from others of their species. In a sort of macabre message to would-be trespassers, the couple will mount their kills around the borders of their land, perhaps in an effort to show others what could become of them if push came to shove. (Did I mention these things actually have a comic book monster named for them? Eat your heart out, Batman.) Unfortunately for them, researchers note that this action often resulted in the prey being snatched by opportunistic passers-by and having to be replaced. It’s so hard to look murderous when everybody keeps stealing your victims…

[Fun Fact: Shrikes with young chicks will often eat only the head of their prey, saving the bodies for the kids. ‘Cause that’s just good parenting.]

Says Who?

• Keynan & Yosef (2010) Behavioural Processes 85: 47-51
• Sarkozi & Brooks (2003) Southwestern Naturalist 48(2): 301-303
• Smith (1973) Behaviour 44(1/2): 113-141
• Yosef & Pinshow (2005) Behavioural Processes 69: 363-367