Grey-headed woodpecker

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Grey-headed woodpecker
Grey-headed Woodpecker - Italy S4E5692.jpg
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Piciformes
Family: Picidae
Genus: Picus
Species: P. canus
Binomial name
Picus canus
Gmelin, 1788[2]

The grey-headed woodpecker (Picus canus), also known as the grey-faced woodpecker, is a Eurasian member of the woodpecker family, Picidae. Along with the more commonly found European green woodpecker and the Iberian green woodpecker, it is one of three closely related sister species found in Europe. Its distribution stretches across large parts of the central and Eastern Palaearctic, all the way to the Pacific Ocean.

The grey-headed woodpecker is more demanding than the European green woodpecker in terms of its habitat. It prefers old mixed coniferous forest with a high proportion of dead trees, feeding primarily on ants, although not being as exclusively dependent on this group as the green woodpecker. The grey-headed woodpecker's nest is typically excavated into dead or severely damaged trees.

The subspecies of grey-headed woodpeckers in the Himalayas and those in Sumatra were defined, in 2014, to be separate species Picus guerini and Picus dedemi, respectively, so that as of 2016, three subspecies remain part of Picus canus.,[3] but IOC World Bird List are still treating P. canus guerini and P. canus dedemi as subspecies.

In the majority of areas for which population numbers are available, the grey-headed woodpecker is in decline. IUCN's Least Concern rating is primarily based on the large distribution of the species.[4]

Description[edit]

A grey-headed woodpecker in Kaeng Krachan National Park, Thailand

The grey-headed woodpecker is 28–33 cm (11–13 in) long and weighs 110–206 g (3.9–7.3 oz). Specimens of the more widespread of the two Eastern subspecies, P. c. jessoensis, are usually a little larger and heavier than individuals from the type locality. On average, it is somewhat smaller and lighter than the European green woodpecker.[5] In the field, this distinction in size is difficult to make. Its size is approximately that of a Eurasian collared dove.

Grey-headed woodpeckers have uniformly olive green upperparts, transitioning across the neck to a light grey, the head being that latter colour. The typical woodpecker markings are small and not particularly conspicuous. It has a grey head with black moustache, and the male has a red crown. It has a shorter neck, slimmer bill and slightly rounder head than the green woodpecker.[6]

Sounds[edit]

Calls made by the European green woodpecker and grey-headed woodpecker resemble each other. The far-carrying territorial song of the grey-headed woodpecker is more melodic and cleaner than the explosive "laughter" of the green woodpecker. The call series consists of ten to fifteen utterances of declining pitch and gradual slowing.[6] The verse may appear melancholic[7] and "dying". The territorial song of females is similar, but somewhat quieter, less melodious, but more croaky and often shorter.[8]

Besides these partner-specific vocalisations, aggressive noises can be heard from both sexes, but more often the male. Typical are individual, sharp kuek sounds that may, with increasing irritation, be placed in sequence and be continued as kek. A single kuek may be also be a predator warning, as begging nestlings will immediately fall silent if this call is made by either parent.[9] Individual drumming activity by grey-headed woodpeckers can be quite varied, but they drum on more occasions than European green woodpeckers. Drumming frequence can be 20 Hertz, with a "drum roll" lasting up to 40 beats, or two seconds.[6] Both sexes drum, but the female less often than the male, and usually more quietly and shorter. Grey-headed woodpeckers often continue to use the same well-resonating drum sites for years – these can even be at a considerable distance from the nest. Grey-headed woodpeckers often use metal covers on masts and roofs as drumming substrate due to their favourable resonance characteristics.[10]

Voice samples[edit]

Taxonomy[edit]

Picus canus, P. guerini and P. dedemi were previously lumped under P. canus.[1]

The Sibley-Monroe checklist has two birds called "grey-headed woodpecker", P. canus and Dendropicos spodocephalus (syn.Mesopicos goertae).[12]

Hybridisation[edit]

There is evidence for hybridisation between grey-headed and European green woodpeckers. However, these seem extremely rare. It appears that the female partner was invariably a grey-headed woodpecker. Nothing has been reported concerning the fertility of such hybrid offspring. Their plumage resembles a grey-headed woodpecker more closely, but with a red parting on the head, a reddish nape and a brighter iris,[13] while some were conspicuous for their dark coloration.[14]

Distribution[edit]

Distribution of the grey-headed woodpecker      Picus canus canus     Picus canus jessoensis     Picus canus griseoviridis (see Korea)

The grey-headed woodpecker is found in wide parts of Central, Northern and Eastern Europe, as well as a wide belt south of the boreal coniferous forests across Asia all the way to the Pacific coast, Sakhalin and Hokkaidō. Its northern limit is at the border between closed coniferous and mixed forest; the southern limit is where tree steppe transitions to treeless shrubby steppe. In East Asia, the species is most differentiated, and south of Manchuria covers the Korean Peninsula, as well as large parts of eastern China and Farther India, the mountain forests of the Malay Peninsula.[1]

In Europe, the type subspecies breeds within a wide belt from western France to the Urals. It has settled medium latitudes of Scandinavia as well as Central, Eastern and Southern Europe. There is contradictory information regarding its occurrence in Turkey. Most likely, several hundred pairs breed in Mittelgebirge habitats of the Pontic Mountains. The species is absent from the North German Plain, British Isles, Iberian Peninsula, and Mediterranean islands. In Italy, it is confined to the northernmost parts.[1]

Food[edit]

Formica rufa is one of the species eaten

The grey-headed woodpecker is a somewhat less specialised ant hunter than the European green woodpecker. In its foraging strategy it is intermediate between many Dendrocopos species on the one hand, and the often ant-specific members of the genus Picus. This reduced ant specialisation of the grey-headed woodpecker allows it to be sympatric with European green woodpeckers and even to breed at about 100 meters from them.[15]

Nonetheless, ants and their immatures make up the lion's share of the grey-headed woodpecker's diet, particularly in spring and summer. Wood ants of the genus Formica as well as members of Lasius and Myrmicinae such as Myrmica spp. predominate, and with termites may make up 90% of the diet.[1] Besides those, caterpillars, crickets, bark and wood beetle larvae, flies, spiders and lice are part of the diet. In late autumn and early winter, grey-headed woodpeckers switch to including significant amounts of vegetable matter, such as berries and other fruits, in their diets on a regular basis.[1]

Behaviour[edit]

Grey-headed woodpeckers live in both deciduous and mixed forests. They breed in May and lay five to ten eggs which are brought up by both parents.[7] The young hatch after 15–17 days, and fledge in 24–25 days.[8]

Eggs of Picus canus

Conservation status[edit]

The grey-headed woodpecker is difficult to record, as isolated breeding pairs don't often call. These are therefore easily overlooked, and population records have corresponding gaps. It is probable that European populations, especially at the north-western margin of the range, have receded in numbers and distribution. Since the 1990s, populations seem to be recovering as a result of mild winters.[16] Globally, there is a slight reduction in population numbers, but insufficiently so for an elevated threat status. The species is therefore considered safe.[17]

The observation of stable or slightly increasing populations in Europe may, however, be based solely on greater effort in recording the species. The overall European population is estimated at 180,000 to 320,000 breeding pairs. Key populations are found in European parts of Russia as well as Romania. Germany has around 15,000 pairs, Austria approximately 2,500 and Switzerland some 1,500.[18] There are no summary figures for populations outside Europe.

As the grey-headed woodpecker prefers undisturbed and ancient forests with natural cohort structure as well as riparian forests for breeding, the destruction of such habitat is the greatest threat to the species.[1]

References[edit]

  1. ^ a b c d e f g BirdLife International (2016). "Picus canus". IUCN Red List of Threatened Species. IUCN. 2016: e.T22726503A86924320. Retrieved 18 January 2017. 
  2. ^ Linnaeus (1788–1793). J.F.Gmelin, ed. Systema Naturae. vol. 1 pt. 1 (13th ed.). Lipsiae. p. 434. 
  3. ^ Winkler, H. & Christie, D.A. (2016). Grey-faced Woodpecker (Picus canus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/56316 on 1 October 2016)
  4. ^ Datenblatt IUCN
  5. ^ Winkler, H. & Christie, D.A. (2016). Grey-faced Woodpecker (Picus canus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/56316 on 5 October 2016).
  6. ^ a b c Gorman, Gerard (2014). Woodpeckers of the World: A Photographic Guide. Firefly Books. pp. 453–455. ISBN 177085309X. 
  7. ^ a b Niethammer, G., Rheinwald, G. & Wolters, H. E. 1983. Zauber und Schönheit unserer Vogelwelt. Verlag Das Beste, Stuttgart, Germany, p. 53. ISBN 387070201X
  8. ^ a b Nikolai, J. 1982. Fotoatlas der Vögel. Gräfe und Unzer, Munich, Germany, p. 241. ISBN 3-7742-3813-8
  9. ^ Handbuch der Vögel Mitteleuropas, 1994, Vol. 9, p. 921ff
  10. ^ Gorman (2004), p. 60
  11. ^ Schweizerische Vogelwarte Sempach.
  12. ^ Sibley, C. G. and Monroe, B. L. (1990) Distribution and taxonomy of birds of the world. Yale University Press. New Haven, USA.
  13. ^ Eugene M. McCarthy: Handbook of Avian Hybrids of the World. Oxford University Press 2006. ISBN 978-0-19-518323-8, S. 109.
  14. ^ Gorman (2004), p. 59.
  15. ^ Gorman (2004), S. 61f.
  16. ^ Bauer/Berthold (1997), S. 283.
  17. ^ factsheet birdlife international (2006).
  18. ^ factsheet birdlife europe (2004).
  • Gorman, Gerard (2004): Woodpeckers of Europe: A Study of the European Picidae. Bruce Coleman, UK. ISBN 1-872842-05-4.

Further reading[edit]

  • Gerard Gorman: Woodpeckers of Europe. A Study to European Picidae. Chalfont 2004, pp. 57–68 and pp. 44; 35. ISBN 1-872842-05-4

External links[edit]