Ladder backed Woodpecker

Birds Name	Ladder-backed woodpecker
Science Name	Dryobates scalaris
Domain	Eukaryota
Kingdom	Animalia
Phylum	Chordata
Class	Aves
Order	Piciformes
Family	Picidae
Genus	Dryobates
Species	D.scalaris

In the early morning hush of a desert canyon, a Ladder-backed Woodpecker may call softly with a sharp “peek” or descending whinny. This desert woodpecker is about 16.5–19 cm (6½–7½ inches) long, with black-and-white bars on its back like a miniature ladder. It is compact and sturdy, roughly the size of a small robin. Adult males have a small red patch on the crown (absent in females), a flash of color that stands out in the muted landscape.

Compared to many other woodpeckers, it is rather petite. The bill is sharp and chisel-like; the body is squat with a straight posture. Its feet are zygodactyl (two toes forward, two back) – an adaptation for clinging to tree trunks and cacti. A stiff tail also helps in bracing.
Table 1 compares the Ladder-backed’s size to a few others.

The Ladder-backed Woodpecker belongs to the woodpecker family Picidae (order Piciformes). Its scientific name is Dryobates scalaris (some references use Picoides scalaris). Dryobates means “tree-walker” and scalaris means “ladder-like,” referring to its barred back pattern. Several subspecies occur in different regions: for example, D. s. cactophilus in the U.S. Southwest and northern Mexico, D. s. lucasanus in southern Baja California, and D. s. leucoptilurus in Belize to Nicaragua. Table 2 lists the recognized subspecies and their ranges.

Ladder-backed Woodpecker subspecies and ranges

Historical synonyms include Picus scalaris and Dendrocopos scalaris. In Spanish it is often called “Pico Mexicano,” and in French “Pic arlequin.”

Distribution, Range and Population

Ladder-backed Woodpeckers are year-round residents of the southwestern U.S., Mexico, and parts of Central America. In the U.S. they occur in southern California, Arizona, New Mexico, west Texas, and portions of adjacent states. Their range extends through most of Mexico (including Baja California and Yucatán) down to Guatemala and Nicaragua. Table 3 summarizes population estimates and status for this species and a few related woodpeckers.

Population and status of select woodpeckers

Survey data suggest Ladder-backed Woodpecker numbers are very large and only slowly declining (on the order of ~1% per year in Texas surveys). With millions of individuals, it remains widespread and common. There is no true migration – birds stay on their territories year-round – though rare wandering individuals have been spotted far outside the normal range.

Habitat

This species specializes in dry, open habitats. It occupies desert scrub, mesquite flats, thorn forest, and dry washes in arid regions. It forages in cactus patches (saguaro, cholla, prickly pear) and in stands of drought-tolerant trees and shrubs such as mesquite, palo verde, and desert willow. It will even nest in dead agave stalks, yuccas, palms or tamarisks, as long as there is wood to excavate. Because it tolerates heat and sparse cover, Ladder-backed Woodpeckers are uncommon in dense forests or very humid climates.

Habitat characteristics (Ladder-backed vs Downy)

Behavior

Ladder-backed Woodpeckers are usually seen alone or in breeding pairs. Their flight is a bouncing, undulating wave of wingbeats and glides. They cling vertically to tree trunks or cactus, using their stiff tail feathers as a brace. Pairs display by raising their crest, bobbing their head, and performing fluttering flights when establishing territory or courting.

Their call is a sharp “peek” or a rolling chatter. They drum quietly on wood or cactus, not as loudly as larger woodpeckers. Both males and females excavate nesting cavities (the male does most of the chiseling). Outside the breeding season they tend to be quiet and well-camouflaged. Like other woodpeckers, they have spongy skull pads to absorb shock and strong toes (zygodactyl feet) for climbing.

Feeding

The Ladder-backed Woodpecker feeds mostly on insects. It probes and gleans beetle larvae, caterpillars, ants (including termites), and other arthropods from bark and cactus. Their small size means they typically search surface crevices rather than drilling deep into wood.

They also eat plant foods opportunistically: cactus fruits (prickly pear and saguaro berries) and agave nectar are enjoyed when available, and they will eat berries or seeds (mistletoe, acorns) if they find them. At backyard feeders, Ladder-backed Woodpeckers will take suet, peanut butter, and sunflower seeds. Often, males and females forage in slightly different niches – one on trunks, one on shrubs – which may reduce competition between the pair.

Breeding

Breeding begins in late winter (January–March). The pair excavates a nest cavity in dead wood, a cactus, or an agave stalk, usually 2–6 meters above ground. Both adults incubate the clutch (the male often taking the night shift). Clutch size is usually 3–6 eggs (though 2–7 has been recorded). Eggs are plain white and about 1.8–2.3 cm long. Incubation lasts about 12–13 days. After hatching, the naked nestlings are fed insects by both parents and fledge roughly 20–25 days after hatching. Ladder-backed Woodpeckers typically raise one brood per year.

Breeding parameters (Ladder-backed vs Nuttall’s vs Downy)

Threats

The Ladder-backed Woodpecker is currently listed as Least Concern, but it faces some pressures. Habitat loss is the main threat: clearing of desert scrub or riparian trees for development, agriculture or grazing removes nest sites and food. Invasive plant control efforts that remove mesquite or cactus can destroy cavity sites. Pesticide use may reduce insect prey. Climate change is a long-term concern: hotter, drier conditions and more extreme droughts/heat waves could alter the desert environment and reduce food availability.

Predators (hawks, owls, snakes) take adults or nestlings occasionally, but no unique predators target them beyond normal background levels. Human hazards (vehicles, windows) are minimal in the sparsely populated habitats. Conservation actions that benefit this species include protecting desert riparian corridors and leaving standing dead trees and cacti. Surveys suggest only slight declines, so it remains common in much of its range.

Migration

Ladder-backed Woodpeckers do not migrate. They are permanent residents of their territories year-round. Some local seasonal movement may occur (for example, birds breeding at high elevations may descend to lower areas in winter), and young birds disperse after fledging. Rarely, an individual wanders far outside its normal range, but most never stray from the Southwest. This year-round residency means that changes in habitat or climate must be endured in place rather than escaped by migration.

Summary

In summary, the Ladder-backed Woodpecker – with its barred black-and-white plumage and the tiny red crest on males – is a resilient emblem of desert life. Its strong population across arid lands and its adaptable nature make it both common and captivating. For beginners and enthusiasts alike, spotting this smart little woodpecker offers a blend of vivid natural history and ecological insight, all wrapped in a small but striking package.