
Thursday, 20 December 2007
Black Woodpecker foraging in winter

Saturday, 15 December 2007
Grey-headed (Grey-faced) Woodpecker: foraging on rock walls


Tuesday, 11 December 2007
Anatomy, structure: feet

Saturday, 8 December 2007
Anatomy, structure: tail

Most woodpeckers have rigid, strong central tail feathers which they use as props and supports when on tree trunks and branches. A sold, firm posture is important when a woodpecker is hacking at timber and the strong tail helps provide this. Note how the tail feathers on this male Black Woodpecker (photo by Gabor Vasuta, Hungary) are splayed and pressed against the branch, acting as stabalisers. The bird is not really perched, but rather presssed against the branch.
Friday, 7 December 2007
Anatomy, structure

Many of these features can be seen well on this photo of Great Spotted Woodpecker here, taken in Sussex, England by David Plummer: http://www.davidplummerimages.co.uk/
Note the broad chisel-shaped bill with a sharp tip, The robust legs and feet with long sharp claws and the overall stout, strong body.
Thursday, 6 December 2007
Signs: acorns


Wednesday, 5 December 2007
Syrian and Great Spotted Woodpeckers excavating together


Tuesday, 4 December 2007
Syrian Woodpecker: unusual plumage

Monday, 3 December 2007
Quiz woodpecker 8
Middle Spotted Woodpecker, Abruzzo NP, Italy

Friday, 30 November 2007
Woodpecker artwork 2

Friday, 23 November 2007
Thursday, 22 November 2007
Tuesday, 20 November 2007
Drumming
Drumming is a form of song, a method of communication that only woodpeckers produce. It is not, as is sometimes presumed, a foraging technique or part of nest hole excavation work. Though woodpeckers make noises on wood with their bills in other ways (when excavating holes and when feeding) this is not drumming. The sounds made by drumming are actually quite simple and though drumming replaces song (as we know it for passerines) it is less complicated. Nine out of ten of Europe’s woodpecker species drum in the true sense. Wrynecks sometimes appear to drum by their nest-holes, very lightly and probably to advertise the site to partner, or to confirm ownership, but this is rarely heard or observed. Wrynecks also occasionally tap at trees but this behaviour may be linked to foraging rather than to communication. Drumming is a very fast series of strikes done with the bill on a hard surface. The special anatomy of the skull facilitates this potentially dangerous behaviour. Muscles in the head and neck contract just before impact and in the process absorb the shock waves made by the drumming. Woodpeckers choose certain areas of a tree (or other surface) and drum there to announce or confirm their presence and claim to territory. They may also drum when alarmed or agitated. Woodpeckers have several favourite drumming posts in their breeding territories and regularly visit and use them in the pre-breeding period. Dry, dead snags and branches are most often used, probably because they resonate better. Drumming posts are always located high up, almost certainly because woodpeckers know that the sound will carry further. Drumming is, and must be, far carrying and this is achieved also by woodpeckers choosing drumming posts, such as hollow snags, that have good acoustic properties. This probably explains why artificial surfaces such as lamp-poles and satellite dishes are sometimes used. Drumming is rarely done on windy days, perhaps because birds have realised the futility of it. Drumming is seasonal and as it replaces song it is mainly, but not only, carried out in the pre-breeding period. It is reduced when pairs are formed. Drumming by male woodpeckers also attracts females and declares to other males that a territory is claimed and occupied. In the pre-courtship phase of breeding Black Woodpeckers, for example, a male will drum hundreds of times per day. Females probably drum in order to keep in contact with males and to reinforce the pair bond and declare territorial rights to other pairs. Some species, especially those with larger territories like White-backed and Black Woodpeckers, indulge in long-distance communication by drumming. Most species also indulge in some light drumming just after leaving or before entering the roost hole and this may be done all year round. Drumming is species specific. The number of beats per second, the cadence, and the rhythm of the phrase can be diagnostic. Other things to consider are duration, intensity, interval between strikes (speed) and changes in tempo. Some species, such as Great Spotted, drum in a rhythmic pattern; others such as Black Woodpecker produce strong, solid bursts. Lesser Spotted Woodpeckers produce more of a rattle than a drum. There is a relationship between the size of the woodpecker drumming and the volume of the drumming, however the volume and quality of any drumming is also dependent upon the surface and condition of the drumming post.
Monday, 19 November 2007
Woodpecker flight

Friday, 16 November 2007
Colour plates from Woodpeckers of Europe
Wednesday, 14 November 2007
Woodpecker artwork

Friday, 5 October 2007
Quiz Woodpecker 6
Sunday, 30 September 2007
Quiz Woodpecker 5
Friday, 28 September 2007
Woodpeckers: juvenile moult
Juvenile woodpeckers begin a partial post juvenile moult at around the time of fledging and this continues until the autumn. In this first moult, juveniles of all ten European woodpecker species replace their primaries, rectrices and overall (body) plumage but some tertials, secondaries, primary coverts and outer greater coverts are retained. One of the ways to age 1st winter birds is the fact that there is often a moult limit in the greater coverts. For example, in Great Spotted Woodpecker where the new adult-type black inner greater coverts, contrast with the old juvenile brownish outer greater coverts. Juveniles have shorter tails than adults, due to all but the central pair of rectrices being shorter than on adults. The odd looking stunted tail of juvenile Black Woodpeckers in flight is due to this tail arrangement. Another interesting case involves Three-toed Woodpecker. Juveniles of this species sometimes begin their moult while still in the nesting cavity. Interestingly, the fifth to seventh innermost primaries are grown and replaced before the birds have fledged and thus they have never been used. This apparent rush to moult is almost certainly an adaptive feature, the result of the need of the species, as a bird of mainly northern latitudes, to complete the moulting task before the end of the short summer season. When the harsh winter season begins birds must be ready to disperse at short notice to new foraging areas, often some distance away, and a delay while moult is completed could prove fatal. For similar reasons, suspended moult occurs in local populations of other species that are prone to eruptive movements such as Fenno-Scandic and Russian Great Spotted Woodpeckers. Juveniles trapped in Fenno-Scandia after arriving from further east in late autumn apparently often exhibit signs of suspended moult in the tail and wing when compared to resident birds. Moult is then resumed sometimes as late as December.
Woodpecker moult
The moult regime of the true woodpeckers is rather unusual and this is related to the lifestyle of the family, in particular to foraging habits and to the breeding cycle. A typical European woodpecker (all except Wryneck) has ten primaries, eleven secondaries, and twelve tail feathers. Primaries 6, 7 and 8 are the longest and P10 is reduced in size in adults but is longer and broader in juveniles. Most adult woodpeckers begin a complete post-breeding moult in late spring or early summer soon after breeding has finished and this lasts into autumn. Primaries are moulted sequentially (ascendant) from P1 and the secondaries from two centres (ascendantly from S1, ascendantly and descendantly from S8). The outermost rectrices are also much shorter than the other tail feathers, the central two being the longest. These two feathers are so important as props when climbing and clinging to vertical surfaces, so they are replaced last, after the other tail feathers. Counting the central two as R1 moult starts ascendantly in pairs from R2 to R6 with R1 last. There is no pre-breeding moult for the true woodpeckers, though Wryneck has a partial pre-breeding moult. Wrynecks moult their tail feathers in reversed sequence.
Wednesday, 26 September 2007
Monday, 24 September 2007
Holes: White-backed Woodpecker - natural hole use

Holes: White-backed Woodpecker

Holes: secondary user - Tengmalm's Owl

Holes: Black Woodpecker as a provider

Saturday, 22 September 2007
Holes: location

Holes: used and unused

Holes: safety

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Friday, 21 September 2007
Holes

Green Woodpecker: photo of male
Thursday, 20 September 2007
Quiz Woodpecker 2
Wednesday, 19 September 2007
Lesser Spotted Woodpecker: adult male photo
Lesser Spotted Woodpecker: races ID

Lesser Spotted Woodpecker: juvenile ID

Lesser Spotted Woodpecker: adult female ID

Lesser Spotted Woodpecker: adult male ID
Lesser Spotted Woodpecker: general ID

Tuesday, 18 September 2007
Quiz Woodpecker 1

Friday, 14 September 2007
White-backed Woodpecker: juvenile lilfordi race ID

White-backed Woodpecker: female lilfordi race ID
White-backed Woodpecker: male lilfordi race ID
White-backed Woodpecker: lilfordi race general ID
The general features described elsewhere in this blog for nominate leucotos apply equally to the southern European race lilfordi. However, there are some striking and important differences in plumage that together with wing and bill measurements, voice, habitat selection and distribution, have resulted in this race sometimes being considered a separate species i.e. Lilford’s Woodpecker. Lilfordi is slightly larger, overall darker and more heavily streaked with long, black, flecks on the flanks, breast and belly. In addition to vertical streaks there are also some horizontal bars on the flanks that nominate lacks. The pink ventral area extends further up onto the belly than leucotos, often onto the lower breast. Under-parts various shades of white, cream, often dusky or tinged buff and always more marked and darker than leucotos. The forehead, lores, cheeks and throat are also more yellow. The black post-auricular stripe and malar stripe are broader and, where they join to form a T-junction, below the ear-coverts, a larger black area is formed. Face patterns may vary slightly from bird to bird but on all the post-auricular stripe runs over the ear-coverts and finishes much closer to, or even touches, the nape. On leucotos it never touches the nape and a wider white gap is clear. Wings have narrower white bars than on nominate. But above all lilfordi lacks the clear white lower-back and upper rump patch of leucotos race. Lilfordi is thus less "white-backed" than leucotos. It is rather "barred-backed" or perhaps "ladder-backed" due to the white-back and upper-rump being vermiculated with black. The rump of this race often seems totally black.
White-backed Woodpecker: juvenile female ID
Juvenile female White-backeds have red colouration only on the fore-crown (adult female has none) but this often rather patchy, and always less than on juvenile male. Sometimes this patch is merely a few red or pink feathers. The true extent of red on the crown becomes evident some twelve days after hatching.
White-backed Woodpecker: juvenile male ID
Juvenile male White-backeds have an all red crown which extends at the back of the head to the black nape and sideways to the white cheeks. This becomes apparent around twelve days after hatching and is more pronounced as birds peep out of the hole prior to fledging. Male fledglings are generally heavier, and have longer bills and tarsi than sibling females though these factors only noticeable in the hand.
White-backed Woodpecker: juvenile ID

White-backed Woodpecker: adult female ID

White-backed Woodpecker: adult male ID

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