Montana Field Guide

Lewis's Woodpecker - Melanerpes lewis

The Lewis's Woodpecker is a medium sized woodpecker, approximately 10 to 11 inches in length. They weigh about 115 grams. Their wings and tail are relatively long (Sibley 2000). The head, back, wings and tail are greenish-black. They have a silver-pale collar and upper breast. The face is dark red and the belly and lower breast is pinkish or salmon-red. The sexes are similar in appearance, but males are usually larger than females (Tabalske 1997). Juvenile birds are distinct from adults, having an overall dark appearance with more brownish-black on the back. They usually lack the silver color of the neck, the pinkish belly color, as well as the red on the face (Tabalske 1997).

Lewis's Woodpeckers are quieter than other woodpeckers. They commonly call during the breeding season only. During breeding male Lewis's will give a harsh "CHURR" call which is repeated 3 to 8 times. Males will also give a chatter call throughout the year and commonly during the breeding season (Tabalske 1997).

The plumage of the Lewis's Woodpecker will easily distinguish it from any other woodpecker species. Also the flight pattern is unique for woodpeckers. Lewis's Woodpecker flight is slow and direct and will often include long glides and aerial maneuvers (Tabalske 1997). From long distances, Lewis's Woodpeckers may be mistaken for a crow or jay, but closer observation of the plumage and form will eliminate any confusion.

Montana Range

Breeding Lewis's Woodpeckers usually begin their southward migration in late August or early September (Tobalske 1997). In Montana, most of the migrating Lewis's Woodpecker observations have occurred in August. In fact, only a single observation of Lewis's Woodpecker exists from September (MBD 2003). Migratory routes to wintering areas are little known, as the species is a highly opportunistic feeder and may be following locally abundant food resources (Tobalske 1997). Spring migration usually begins in early April and most birds arrive on their breeding grounds by mid-May. In Montana, the earliest spring record for Lewis's Woodpecker is from the Deer Lodge area in April. All other spring migration observations are from May (MBD 2003).

In the Bozeman area, Lewis's Woodpeckers are known to occur in river bottom woods and forest edge habitats (Skarr 1969). No other specific habitat information for Montana is currently available. Habitat information from other Lewis's Woodpecker sources state that the breeding habitat is open forest and woodland, often logged or burned, including oak and coniferous forest (primarily ponderosa pine [Pinus ponderosa], riparian woodland and orchards, and less commonly in pinyon-juniper [Pinus spp.-Juniperus spp.]) (AOU 1983). Lewis's Woodpecker distribution is closely associated with open ponderosa pine forest in western North America, and is strongly associated with fire-maintained old-growth ponderosa pine (Diem and Zeveloff 1980, Tobalske 1997, Saab and Dudley 1998).

Important habitat features include an open tree canopy, a brushy understory with ground cover, dead trees for nest cavities, dead or downed woody debris, perch sites, and abundant insects. Lewis's Woodpeckers use open ponderosa pine forests, open riparian woodlands dominated by cottonwood (Populus spp.), and logged or burned pine. They also use oak (Quercus spp.) woodlands, orchards, pinyon-juniper woodlands, other open coniferous forests, and agricultural lands. Apparently the species prefers open ponderosa pine at high elevations and open riparian forests at lower elevations (Bock 1970, Tobalske 1997). In the Blue Mountains of Oregon, they showed a preference for open stands near water (Thomas et al. 1979). Because the species catches insects from the air, perches near openings or in open canopy are important for foraging habitat (Bock 1970, Tobalske 1997).

Lewis's Woodpeckers often use burned pine forests, although suitability of post-fire habitats varies with the age, size, and intensity of the burn, density of remaining snags, and the geographic region. Birds may move to unburned stands once the young fledge (Block and Brennan 1987, Tobalske 1997, Saab and Dudley 1998). They have been generally considered a species of older burns rather than new ones, moving in several years post-fire once dead trees begin to fall and brush develops, five to thirty years after fire (Bock 1970, Block and Brennan 1987, Caton 1996, Linder and Anderson 1998). However, on a two- to four-year-old burn in Idaho they were the most common cavity-nester, and occurred in the highest nesting densities ever recorded for the species (Saab and Dudley 1998). As habitat suitability declines, however, numbers decline. For example, in Wyoming, the species was more common in a seven-year-old burn than in a twenty-year-old burn (Linder and Anderson 1998). Overall, suitable conditions include an open canopy, availability of nest cavities and perches, abundant arthropod prey, and a shrubby understory (Linder and Anderson 1998, Saab and Dudley 1998).

Unlike other woodpeckers, Lewis's Woodpeckers are not morphologically well adapted to excavate cavities in hard wood. They tend to nest in a natural cavity, abandoned Northern Flicker (Colaptes auratus) hole, or previously used cavity, 1 to 52 meters above ground. Sometimes they will excavate a new cavity in a soft snag (standing dead tree), dead branch of a living tree, or rotting utility pole (Harrison 1979, Tobalske 1997). The mated pair may return to the same nest site in successive years. On partially logged burns with high nesting densities in Idaho, nest sites were characterized by the presence of large, soft snags and an average of 62 snags per hectare that had more than 23-centimeter diameter at breast height (dbh) (Saab and Dudley 1998).

In late summer, wandering flocks move from valleys into mountains or from breeding habitat to orchards. In winter, they use oak woodlands and nut and fruit orchards. An important habitat feature in many wintering areas is the availability of storage sites for grains or mast, such as tree bark (e.g. bark of mature cottonwood trees) or power poles with desiccation cracks (Bock 1970, Tobalske 1997). In southwestern Arizona and southeastern California, Lewis's Woodpeckers may use scrub oak, pecan orchards, and cottonwoods, but more study is needed in this area (Bock 1970). In Mexico, they use open and semi-open woodlands, especially those with oaks (Howell and Webb 1995).

No specific information on food habits for Lewis's Woodpecker is available for Montana. Information from studies in other areas of the species' range indicate that Lewis's Woodpeckers feed on adult emergent insects (e.g., ants, beetles, flies, grasshoppers, tent caterpillars, mayflies) in summer, and ripe fruit and nuts in fall and winter. They are opportunistic and may respond to insect outbreaks and grasshopper swarms by increasing breeding densities. Unlike other woodpeckers, the Lewis's Woodpecker does not bore for insects but will flycatch and glean insects from tree branches or trunks; they also drop from a perch to capture insects on the ground. The species especially favors acorns and commercial nuts and fruit in fall and winter, and caches food in natural crevices such as tree bark and desiccation cracks in utility poles, tailoring food to fit crevices. They also eat huckleberry, twinberry, currant, mountain ash and chokecherries (Bock 1970, Tobalske 1997). In some areas, wintering birds rely more on insects than on cached food (Hadow 1973).

There is very little ecological information from Montana. Lewis's Woodpeckers were reported as less common in the Bozeman area in the 1960s than in the 1880s, and less common near Fortine in the 1970s than before 1945 (Skaar 1969, J75WEY01). Other ecological information comes from work in other areas of the species' range. Lewis's Woodpeckers will aggressively defend food caches and they are territorial in immediate space around nest sites toward Red-headed Woodpeckers (Melanerpes erythrocephalus) and other Lewis's Woodpeckers; however, they may nest semi-gregariously where several nest cavities are close together (Bock 1970, Bock et al. 1971, Tobalske 1997). Breeding season territories were reported to vary between 1 and 6 hectares in the Blue Mountains of Washington and Oregon (Thomas et al. 1979). Foraging home ranges broadly overlap and large numbers of birds may forage together where there is a local abundance of food (Tobalske 1997).

Little information exists regarding Lewis's Woodpecker reproduction in Montana. Near Fortine, eggs were incubated during June. Dates for young in the nest range from June 22 to August 4. However, information from other areas where Lewis's Woodpeckers occur indicates that they form a life-long pair bond. The clutch size is five to nine (usually six to seven). Incubation, by both sexes, lasts 13 to 14 days. Young can fly 28 to 34 days after hatching (Terres 1980, Ehrlich et al. 1988).

No known active management is ongoing for Lewis's Woodpecker in the state. However, management for Lewis's Woodpeckers in dry forests fits very well with the management needs for Flammulated Owls. The landscape-level needs of the Flammulated Owl would probably accommodate any habitat-area needs of Lewis's Woodpeckers. Specific needs of the Lewis's Woodpecker at the microsite and site level could be met in the form of interspersed zones of shrubby understory within the overall habitat mosaic (Casey 2000). Recommendations for snag retention in forest management plans have been developed (Thomas et al. 1979). To sustain a maximum density of Lewis's Woodpeckers (16.6 pairs per hectare) a density of 249 snags per hectare, more than 30.4 cm in diameter at breast height (dbh), and more than 9 meters in height must be maintained in ponderosa pine, riparian cottonwood and mixed-conifer forest (Thomas et al. 1979).