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Image Credits: lower sketch by Rob Cannings in Birds of the Okanagan Valley, British Columbia, Campbell et al., 1987. Top photo and middle sketch in The Birds of British Columbia, Campbell et al., 1990.
Historical facts The British Columbia population of the White-headed Woodpecker has apparently fluctuated widely over the last fifty years. The species was considered very rare in the late 1950s and early 1960s, but became fairly common in late 1960's and early 1970's. In the late 1970s, it was very rare again for unknown reasons. The British Columbia population was under 100 birds when last surveyed in 1990. The last nest was found in 1980. The White-headed Woodpecker, a member of the family Picidae, is our only woodpecker with a white head and wing patches (males have a red patch on the nape of the head), and the sharply contrasting black of the remaining plumage of the body. This woodpecker can be mistaken for no other bird; young resemble the adults, but are dull in colour and have shorter bills. Young males and females sometimes have reddish markings on the head as does the adult male.
Map
British Columbia
North America The White-headed Woodpecker requires mature ponderosa pine stands restricting it, more or less, to the benches and hills of the Okanagan Valley below 600 or 700 m. They have also been found in ornamental gardens, mixed ponderosa pine/Douglas-fir forest, Douglas-fir forest, Engelmann spruce/lodgepole pine forest and black cottonwoods. The primary limiting factor for populations of the White-headed Woodpecker in Canada is the dependence of the species on mature to old-growth ponderosa pine forests. This dependence is likely related to both the availability of snags for nesting and roosting as well as the availability of cones for foraging. Most of the old-growth ponderosa pine forests of British Columbia were heavily logged in the 1930s and 1940s and only scattered remnants remain, usually in sites with difficult access. Some of these have recently been harvested by helicopter logging operations, but this practice has been stopped for the time being. If White-headed Woodpeckers are dependent on large pine seeds as food in late summer, fall and winter, it is the availability of this resource which may be the most important limiting factor to its population size. Ponderosa pines produce good cone crops only every four to five years in the Pacific Northwest, and no other suitable pine species are found throughout the northern part of the White-headed Woodpecker's range. Seed production by ponderosa pines is also related to the age and size of the trees and the density of the stand; almost all seeds are produced by large, dominant trees in open situations. As a result of logging and subsequent fire suppression, many ponderosa pine forests in the Okanagan Valley are now characterized by dense stands of young trees, presumably resulting in poor seed production there. Reduced snag densities after even selective logging would likely seriously lower the quality of White-headed Woodpecker nesting habitat. As well, the habit of nesting low in snags may increase nest predation pressure. Since insects are an important food source for White-headed Woodpeckers, particularly in the summer, pesticide application in ponderosa pine forests would likely have a significant impact on woodpecker populations.
Breeding There is no evidence for more than one brood per season; young have been found in British Columbia nests from the end of May to the middle of July. Nesting has occurred in Douglas-fir snags but ponderosa pine is more frequently used and ponderosa seeds are choice feed, especially in winter. The White-headed Woodpecker tends to nest in open-canopied stands of mature and overmature trees. Grand fir, subalpine fir, and lodgepole pine forests are of secondary importance. They build their nests in the oldest, softest snags which are short, have large diameters and no small branches. Nesting-holes are drilled low down in trees which, while having a hard outer shell, are usually decayed and "punky" within, for this woodpecker is not an accomplished driller. The skull formation is much weaker than in other woodpeckers.
Behaviour The minimum territory size for the White-headed Woodpecker is about 8 hectares but considering the low population densities in the northern part of its range, territory sizes in British Columbia are likely much larger than this. The voice is described as a single "wick" or when excited the female calls " 'cheep-eep-eep-eep' very fast and repeats the call every few seconds. The male under similar circumstances calls 'yip, yip, yip, yip' in a much shriller tone, but in slower time."
Diet or Growing requirements In British Columbia, the White-headed Woodpeckers have also been observed feeding on stalks of great mullein, a common weedy plant in disturbed areas in the southern interior. These birds were presumably eating the seeds of this plant, but may have been searching for insects as well. The Woodpecker has also been known to eat suet.
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