The Loggerhead Shrike: Looks Can Be Deceiving
At first glance, you could be forgiven for thinking that that grey-and-white bird sitting on a fencepost or atop a thorny shrub is a common mockingbird: Roughly the same in body size and coloration, the loggerhead shrike also has a black bandit’s mask streaked across its eyes. And with its dainty perching feet and a plump-yet-delicate body, the loggerhead looks like something you might find flitting around a cartoon princess’s head. But then, look a little closer and you’ll see that the little bird’s beak has a hook like a falcon. And yes, it’s used for exactly what you think it’s used for.
Loggerhead shrikes are sweet-looking songbirds that rip their prey to shreds and festoon their territory with their mutilated corpses.
Known in the American South as the butcher bird, the loggerhead has a whole roster of other nicknames in various other languages that illustrate its peculiar and very non-passerine habit of not only hunting, but impaling prey on thorns, barbs and twigs within its territory. In Mexico, it’s Verdugo Americano: the American hangman, or executioner, depending on whom you ask. In German, it’s the Louisianawürger, the Louisiana slayer. Even the loggerhead's Latin name reflects its gruesome dietary habits: Lanius ludovicianus translates to “Louisianan butcher." (And here we should note that while the loggerhead is one of only two shrike species that breed in North America, there are about 30 species of shrikes in the world, including 27 that share the same genus, Lanius, owing to their similarly grisly tendencies.)
It doesn't quite seem fair that the loggerhead's eating habits should brand it so—after all, hawks do the same thing, and we just call them hawks. But perhaps those bird-namers just take a perverse delight in the contrast between the loggerhead's innocent appearance and its gruesome lifestyle. Here's how it all goes down: Loggerheads will wait patiently atop their post, hunched over, peering down at the ground, until they spy a target—it might be insects in the summer months, but when the days get cooler and the bugs get scarce, the loggerhead will turn to rodents, lizards, and other birds. Then the loggerhead will swoop down and direct a targeted attack at the back of its prey's neck, at the base of the skull. Loggerheads’ sharp, hooked beaks are equipped with an extra barb also found on raptor beaks, the tomial tooth, and as the loggerhead bites down, this barb slips between the cervical vertebrae, damaging or severing the spinal cord. Then, clutching the kill with its puny feet, the loggerhead hauls its prey—sometimes as large as itself—back to a waiting barbed-wire fence, hawthorn tree, or locust hedge, where it promptly hangs its prize on a meathook. Thus stabilized on a thorn or twig, the loggerhead can settle down to dine without having to hold its meal.
You’ll never forget Loggerhead Shrike territory once you’ve stumbled upon it (usually adjacent to shrubby, scrubby fields), because loggerheads tend to sprinkle bodies around their territories, a behavior that is thought to serve a variety of functions. First, it’s to have a well-stocked larder—he who does not save will suffer, as the Confucian saw goes. (That said, many a farmer or rancher may tell you that prey is forgotten as often as eaten, and regale you with tales of mummified frogs decorating their fence lines.) Hanging certain insects to age for a couple of days may also render them edible by allowing toxins to dissipate. Second, the insects, mice and sundry serve as a sign to other shrikes that the territory is occupied. And lastly, like a colorful and abundant market stand, a male shrike’s stash shows potential mates that he is a capable provider.
Yet despite their killer instincts, loggerheads, once plentiful along grasslands from the South to the forests of Canada, are in decline. Though locally abundant in areas where they live year-round, migrant populations seem inordinately affected, and scientists are counting fewer birds overall where they formerly thrived. Though the causes are unclear, some researchers attribute the falloff in part to disappearing habitat; the grasslands and abandoned fields where loggerheads thrive are increasingly gobbled up by development and croplands.
Breeding programs are in place at several research institutes, universities and zoos to help boost numbers, but until the exact causes of the loggerhead’s wane are identified, impaled mice may be an increasingly rare sight. So next time you’re out on a ramble through an old field, keep your ears open for the rusty creak of the loggerhead’s voice, and your eyes peeled for their deliciously macabre decor.