BLANE KLEMEK COLUMN: Fascinating and deadly shrikes of Minnesota
Sometimes called by their nickname, “butcher bird,” although I’ve never been one to call them that, few birds in Minnesota are as rarely seen or understood as shrikes. A bird of interesting, albeit implausible, habits, their appearance, peaceful-seeming dispositions and anatomical features bespeaks of the songbird they are rather than the raptor they behave like.
Minnesota is home to two species of shrikes: northern shrike (Lanius excubitor) and the loggerhead shrike (Lanius ludovicianus), the latter being the rarer of the two. Loggerhead shrikes are smaller than northern shrikes and have less pronounced, hooked beaks than that possessed by the larger northern shrike. As well, the loggerhead, though only now known in the past 25 years or more to occur in usually just two Minnesota counties -- Dakota and Clay, with some scattered observations reported elsewhere -- loggerhead shrikes are summertime residents of our state while northern shrikes are wintertime residents of Minnesota.
Both species of shrikes have a distinctive black bands, or “masks” across their eyes. Although somewhat difficult to distinguish in the field, especially since both species won’t normally be observed side-by-side, the loggerhead shrike’s black band is wider and extends above the bill, whereas northern shrikes’ facial mask is narrower and does not extend above the bill. Another useful distinguishing feature is the breasts of northern shrikes are faintly barred, whereas the breasts of loggerheads are usually plain with no barring patterns, and are instead a solid grayish color.
Earlier this November I was fortunate to once again observe a northern shrike. While hiking across a prairie field on land owned by The Nature Conservancy in Kittson County, I first saw the shrike fly over several clumps of willow and other scattered clusters of brush and solid stands of big bluestem grass. As the bird flew low overhead, a flock of nearby dark-eyed juncos sounded their alarm, obviously recognizing the shrike as a predator. The shrike alighted onto the top of a tall clump of brush and perched there for a moment, giving me time to examine the beautiful bird through my binoculars before flying off to continue its hunt.
You might recall when I once wrote about the memorable experience that my son and I shared one late afternoon while hunting deer in Kittson County many years ago. We watched in amazement a northern shrike chasing a downy woodpecker out from a nearby woodland into a small forest opening where we happened to be, too.
In flight, the larger and stronger shrike swiftly overpowered the woodpecker by driving the downy to the grass-covered ground, where both birds suddenly found themselves and with the shrike standing on top of the screeching woodpecker. Quickly, the northern struck the back of the woodpecker’s neck twice with its strong beak, which instantly killed the bird. As the shrike examined its prey for a moment, it suddenly noticed us gawking at it from scarcely 10 yards away. So intent on capturing its prey, the shrike hadn’t noticed us, despite our being clad in blaze orange clothing.
The rare loggerhead shrike prefers grassland habitats, of which very little remain in Minnesota and the primary reason why their abundance is so limited. Loss of habitat from farming practices, development, and encroachment of trees onto grasslands are just a few of the possible reasons affecting loggerhead abundance.
Loggerhead shrikes acquired their unusual name because, relative to its body size, they have large heads. Northern shrikes are named as such because of where they spend their summers. These shrikes migrate to the Canadian Yukon and Northwest Territories, northern Quebec and central Labrador, as well as Alaska to raise their broods every year. Winters are spent throughout Minnesota and other northern-tier states.
Shrikes are independent birds that prefer hunting alone. Indeed, of all the shrikes I have observed over the years -- which aren’t many -- I’ve never observed two at the same time. Scanning the ground for prey from the limbs of trees, shrikes will suddenly dive and fly above the vegetation as it prepares to attack, or, as in the case I described earlier, will overtake slower and smaller birds in flight.
Prey is captured by dropping on top of the quarry. Shrikes feed on a wide variety of animal matter, including beetles, grasshoppers, caterpillars, wasps, crickets and other invertebrates. However, the majority of their diet, particularly in the wintertime for northern shrikes, is larger prey such as mice, voles, lemmings and birds.
Since shrikes cannot securely grip their prey with large and strong feet equipped with sharp talons as owls, eagles, hawks and falcons have, shrikes commonly impale or wedge their prey items onto the thorns of woody and herbaceous plants, onto barbs of barb wire fences, or into fissures of branches and bark. Their hooked bills do the rest of the work as they tear off small bits to swallow. Like owls, shrikes regurgitate tiny pellets of undigested parts such as hair, exoskeletons of insects and bones.
Shrikes are among the most fascinating and handsome birds in Minnesota. While a first-time observer may never guess them to be predatory in habit, these mid-size birds are more raptor-like than the songbird they really are as we get out and enjoy the great outdoors.
Blane Klemek is a Minnesota DNR wildlife manager. He can be reached at firstname.lastname@example.org.