Friday, 14 September 2007

White-backed Woodpecker: general ID

Measurements: Length 24-26 cm. Wingspan 38-40 cm, hence the largest Dendrocopos woodpecker in Europe, some 2-3 cm longer than Great Spotted and Syrian Woodpeckers. White-backed is not a difficult woodpecker to identify once found, usually immediately appearing to be rather long-necked and long-billed. The nominate leucotos race is described here (lilfordi in another post). Birds do indeed have a white upper-rump and lower-back but they are not as “white-backed" as their name suggests. The upper back is glossy black and the white on the back below this is sometimes obscured and difficult to see. Rather, it is the white barred coverts, particularly the upper broad white bar of the median coverts that are seen. When a bird takes flight the large white area composed of the lower scapulars, lower back and upper rump comes into view. In most cases this white area is crescent-shaped and connects with the uppermost wing bars. However, on some birds this white area is only slightly broader than the white upper-wing bars. The amount of white on the lower back also varies. There can also be significant variation between birds in the shape and extent of their white back. Individual plumage variations can sometimes exist between populations and sometimes within them. The wings are black but dotted with white on the greater coverts. The flight feathers are crossed by rows of large white spots that almost form bars. White bars on the upper-wing, are often obscured by the white back patch, which sometimes forms a broad fringe across the back. The broad white bar on the upper-wing is striking when in flight and on perching birds seen from side. On a rear view heavy white barring can be seen to extend across the closed tertials (unlike Great Spotted and Syrian). The scapulars are glossy black. The upper-tail coverts and most of the rectrices are black. The outer rectrices are white with thin black barring. The ventral region and under-tail coverts are pink, never red, and not strongly demarcated from the whitish belly (as Great Spotted). The pink extends up and merges into the lower belly and sometimes colours the flanks and leg feathering (as Middle Spotted). Under-parts are white or cream, but often with a yellowish hue. Long black streaks cover the flanks, and sides of the breast and belly (as Middle Spotted). Despite having pink and yellow areas on the under-parts, White-backed Woodpecker always shows much white in flight. The face pattern can vary slightly from bird to bird but typically the black malar stripe starts from the lower mandible (unlike Middle Spotted) and meets the post-auricular stripe on the side of the neck to form a black T-junction. From here a black stripe runs down to the sides of the neck and onto the upper breast, and below this the black flank streaking is strongest. The post-auricular stripe runs over and across the ear-coverts towards the nape, but not touching it (like Syrian and Middle Spotted but unlike Great Spotted). Face, chin and throat are all white but buff behind the eye. On a rear view a black linking stripe from black nape down to glossy black mantle can be seen (recalling Middle Spotted). The forehead and lores are greyish. The bill is grey, long and very thin at the tip, the iris reddish brown and the legs and toes grey. The photo here is of an adult male leucotos race, taken in the Bükk Hills, Hungary (László Nehézy).

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