Well Worth the Search— Lewis’s Woodpecker
What bird climbs trees like a woodpecker but feeds mostly by acrobatically sallying forth from a perch or circling high in the air to catch flying insects? What chops up acorns and other nuts, stores them the crevices of tree bark, and guards them all winter—at times, having stand-offs with also-acorn-stashing Acorn Woodpeckers where their ranges overlap? What boasts the color palette of a tropical bird: a dark iridescent green back, silvery gray collar and upper breast, dark red face, and salmon-red lower breast and belly? It’s one of the U.S.’s oddest woodpeckers—the Lewis’s Woodpecker—and it has been showing up surprisingly close to the San Diego County coast this winter.
Lewis’ Woodpeckers are uncommon winter visitors to San Diego County, although the numbers wintering here can vary greatly from year to year. They occur mainly in the mountains and foothills, seeking large trees at the edges of meadows or scattered in grassland. Their distribution is patchy, often associated with storable mast in the form of acorns, nuts, or corn. They winter primarily above 1000’ elevation, rarely within 20 miles of the coast. Some years, though, birds reach the coast or the desert floor. This winter, as of this writing (late January), the species has been reported in Ramona, San Marcos, Escondido, San Diego—even Santa Catalina Island. (Okay, that’s not in San Diego County. But it makes a point. You don’t get much more out-of-range coastal than that.) Fall arrival is generally in late September or early October; the latest report, in 2020, was early June.
During breeding season, Lewis’s Woodpeckers feed almost exclusively on emergent insects rather than on grubs that other woodpeckers dig from trees. They maneuver up and down trunks with the hitching aplomb typical of other woodpeckers, but they rarely bore for insects. They also forage on the ground but don’t dig in the soil (as a Northern Flicker does). Over streams, ponds, and wet meadows, they will take advantage of locally abundant hatches of insects. Scanning almost continuously for insects between fly-catching bouts, they use snags, telephone poles, fence posts, and other locations for perches while kingbird-style fly-catching like a feathered boomerang. After the nesting season, when insect numbers decrease, Lewis’s feed on berries, corn, and acorns, which they cache in holes, crevices, and furrows in tree bark.
The Lewis’s Woodpecker’s scientific name, Melanerpes lewis, begins as “black creeper,” from Greek melas(“black”) and erpein or erpo ("to creep”). This moniker refers to the behavior of creeping up and down tree trunks. The species name, both scientific and common, honors Meriwether Lewis, who collected the type specimen on the Lewis and Clark Expedition. Finally, “woodpecker” describes the feeding and nest excavation behavior (although not so much for the Lewis’s Woodpecker, as noted above).
By nearly all accounts, the Lewis's Woodpecker is a rather un-woodpecker-y woodpecker. It might have “woodpecker” in its name, but it forages like a flycatcher, flies with rowing wing beats like a crow, has the Technicolor plumage of a tropical bird, and sports a wimpy beak that can’t meaningfully peck wood. Keep your eyes open for this lovely oddity during the next few months, while this special visitor might still be wandering our area.