It wears a black mask, not a COVID mask but one about the eyes like the Lone Ranger or Zorro. It can hover like a helicopter or fly fast like a fighter plane. And its actions when feeding itself have earned it the frightening moniker, “butcher bird.”
The black-masked loggerhead shrike (Lanius ludovicianus) is like a raptor (bird of prey) in a songbird’s body. Although it weighs at less than 2 ½ ounces or about 65g, it has the aggression and killer instincts of a predator including all the tools it needs to kill their prey and tear it apart.
The bird has a very sharp hooked bill, the upper cutting edge of which is called the “tomium.” On either side of that edge are two projections called “tomial teeth” which allow the shrike to sever the spinal cord of its vertebrate prey. These adaptations are also found in raptors like falcons, which use them the same way. The tomium and the tomial teeth make the shrike quite efficient at dissecting its prey, much like a butcher cutting up a side of beef, which led to the nickname, “butcher bird.”
The loggerhead shrike, so named in reference to bird’s head which seems disproportionately large compared to its body lives in grasslands and other open-space habitats across North America. They hunt from atop utility poles, fence posts, and other open conspicuous perches. Their prey includes large insects like grasshoppers and beetles, arachnids like spiders and scorpions, lizards, snakes, frogs, turtles; small mammals like voles, mice, and ground squirrels; and small birds like sparrows and goldfinches.
A loggerhead shrike can kill and carry prey as massive as itself. The bird will transport large prey in its feet and carry smaller items in its beak.
Because the birds lack a raptor’s talons (they are songbirds after all) with which to hold onto prey while they eat it, they’ve devised another method. They skewer their kills on large thorns or barbed wire, or they wedge them into tight places, so their meal stays put while they tug and tear bits off.
A shrike may leave its meal skewered or wedged for a few days to tenderize a little, or in the case of prey that may contain toxins, like some insects and amphibians, such “resting” time allows poisons to break down before they eat it. The shrike is one of the few predators that can eat the lubber grasshopper, a large, flightless, destructive, invasive pest in some parts of the country whose thorax is poisonous.
Both male and female shrikes pick the site where their nest will be built, and many times that place is in thorny vegetation that helps keep predators away. The average height of their nests is only 30 to 48 inches above ground. When there are no suitable trees or bushes in which to build a nest, brush piles or tumbleweeds sometimes suffice.
Young loggerhead shrikes that have just left the nest, or fledged, have been observed performing exaggerated versions of adult hunting behavior, though without a target. They will peck at inanimate objects or carry them around in their beaks. They’ll practice aerial chases even though they don’t seem to be pursuing anything or sometimes they’ll just chase their parents.
Young shrikes also seem to practice their impaling skills. They will grasp an object with the tip of their bill and repeatedly touch that object to a branch or perch, as if they were trying to get it to stick and stay there. Someday a real meal will stick around a thorn.
National Wildlife Refuge and the San Joaquin River National Wildlife Refuge comprise the San Luis National Wildlife Refuge Complex. Its headquarters and visitor center are located just north of Los Banos off Highway 165 at 7376 South Wolfsen Road.
The refuges are open to visitors daily from one half-hour before sunrise to one half-hour after sunset. The visitor center is open Monday through Friday except federal holidays from 8 a.m. to 4:30 p.m. For more information, call the refuge visitor center at 209-826-3508, ext. 127 or check out the upcoming events on the website at fws.gov/refuge/san-luis
