Corsican Nuthatch Sitta whiteheadi Scientific name definitions

12 cm; 11·8–14·4 g. A small nuthatch with rather long bill and prominent broad white supercilium. Male in fresh plumage (autumn) has glossy black cap from forehead to nape (ill defined at rear), faintly buff-washed white supercilium (from nostril) to side of mantle and ending irregularly at rear, black eyestripe finely spotted white behind eye and less well defined at rear of ear-coverts (merging irregularly into mantle); upperparts , including lesser and median upperwing-coverts, blue-grey; greater wing-coverts and flight-feathers dark grey-brown, tertials washed blue-grey on outer web, greater and primary coverts, secondaries and inner primaries narrowly fringed blue-grey, primaries P3-P6 finely fringed blue-grey inward of emarginations, secondaries and inner primaries finely tipped white (only when fresh); central tail feathers dull blue-grey, other rectrices sooty black, tipped grey (widest on outermost feather), outer three pairs marbled with white subterminally, especially on inner webs; cheek, ear-coverts, chin and throat white, washed dirty buff, side of neck and underparts pale drab grey, variably tinged buff, especially on flanks, belly and undertail-coverts; underwing-coverts and axillaries whitish, median under primary coverts medium grey, base of primaries white (not strongly contrasting); in worn plumage (summer), crown slightly less glossy, upperparts duller and less blue, flight-feathers abraded and bleached paler, supercilium, throat, cheek and ear-coverts whiter, underparts duller, light greyish with little or no buff wash; iris dark brown, narrow white eyering; bill slate-black to grey-brown, more bluish at base of upper mandible, base of lower mandible pale grey to whitish; legs dark grey-brown or slate-grey, soles sometimes yellow. Female resembles male, but crown and ear-coverts medium blue-grey (as upperparts), dark feather centres largely or totally concealed but may show as slightly darker mottling on (usually) forecrown and forehead, especially in worn plumage (exceptionally, dull blackish forecrown); eyestripe grey and less well defined behind eye, supercilium and underparts tend to be greyer. Juvenile is as adult but slightly duller overall, with faint brown tips on greater upperwing-coverts, pale base of lower mandible more extensive, legs paler grey; cap of very young male may be sooty black with no gloss, and juvenile female lacks blackish feather bases on forecrown.

Inland mountain ridges on Corsica (from Tartagine S to Ospedale and Mt Cagna).

Primarily forests of Corsican pine (Pinus nigra), characterized by heavy autumn and winter rainfall and rather dry summers; especially unmanaged pure stands of tall trees (some 300 years old, producing greatest quantities of seeds) with abundant standing dead and rotting trunks and occasional clearings. Lower densities (less than 20% of maximum density) in young forests, mature stands under heavy management, and where Corsican pines mixed with cluster pine (Pinus pinaster), beech (Fagus sylvatica) or silver fir (Abies alba), usually below 1000 m (but can reach high densities in stands of cluster pine at c. 800 m); densities low also above 1500 m, where trees scattered and stunted. In winter some dispersal, occasionally to cork oak (Quercus suber) forest, sweet chestnut (Castanea sativa) plantations and villages at lower altitudes, although still favours pines overall. Found at 750–1800 m during Apr–Oct, with breeding recorded at 760–1600 m, optimum 1000–1500 m; down to 300 m, and rarely even at sea-level, in non-breeding season.

Resident. Territorial adults almost completely sedentary, probably a reflection of their seed-hoarding behaviour. Some dispersal in winter to slightly lower altitudes, usually by immatures and unmated adults; such movements most frequent following snowfalls, when recorded in valleys of C Corsica at 300–600 m, and even at sea-level towards W coast (at Calvi) in Oct and in E (Aleria plain) in Jan.

Food largely insects and spiders  (Araneae) during May–Aug, switching to seeds , especially those of Corsican pine, during rest of year. Forages in pairs and singly; outside breeding season, may join mixed-species flocks. Forages in manner of a tit (Paridae) in needle clusters and among small branches, especially in spring and summer, also (particularly in winter) on trunks and larger branches. May hover to pick  small items from cones etc., and can also flycatch. From late autumn to early spring (i.e. when cones are mature), and during sunny weather (i.e. when cones are open), extracts seeds from cones and caches them behind bark, or places seeds on thicker branches and covers them with fragments of bark or lichen; retrieves cached seeds in cold and wet weather. These stores probably essential to survival, especially in early spring when snow prevents access to pine cones.

Contact call a soft, whistled “pu”, singly or in groups of 5–6 notes, sometimes as rapid trilling “pupupupupu…”, especially immediately prior to or during flight; also gives thin, sometimes lisping “tsi-tsi-tsi” and nasal “pink”, often in irregular series; in agitation a hissing “psch-psch-psch…” and a nasal note like sound from toy trumpet, becoming louder and harsher in excitement or alarm; also a repeated harsh “chay-chay-chay” or “sch-wer sch-wer” similar to call of distant Eurasian Jay (Garrulus glandarius), and increasing in intensity as excitement heightens, when may lose harsh quality and become more musical. Song , fairly regularly in spring, a repetition of single clear, high-pitched note at c. 15 notes per second to produce rapid, sometimes quavering trill , “hidididididid…”, also slower variant of pure, ascending whistled “dew” or “dui” notes at c. 10 per second; the two may be combined, as “dewdewdewdewdew-di-di-di-di-di”.

Season mainly Apr–May, and laying dates synchronous, generally at end Apr or in first ten days May; may be double-brooded. Mated partners remain on territory all year. Nest, built by both sexes, a coarse foundation of pine needles, wood chips and bark pieces, lined with hair, feathers, moss, lichen or plant fibres, placed in cavity  1·6–30 m above ground in medium-sized to large dead or dying Corsican pine, usually in dead pine stump (200–300 years old at time of death) 3·5–22 m high and well rotted; cavity generally excavated by birds themselves, work carried out by both sexes, majority of excavations exploit hole originally started by woodpeckers (Picidae), and some, in very rotten trunk, may have two entrances; living pine with rotting top occasionally used. Clutch 5–6 eggs , white, speckled reddish, especially at broader end, sometimes with light brown or dark violet-grey markings, mean size 17·3–13 mm; replacements laid if clutch fails; incubation by female, fed on nest by male , no information on duration of incubation period; chicks fledge after 22–24 days.

VULNERABLE. Restricted range species: present in Corsican Mountains Secondary Area. Uncommon and somewhat local; occurs on inland mountain ridges from Tartagine S to Ospedale and Mt Cagna, with main concentrations around the mountains of Cinto, Rotondo, Renoso and Incudine; absent from Nebbio and Cap Corse. Population estimated in early 2008 at only 1550–2200 occupied territories (= breeding pairs) in an area of 185 km² (2 Thibault, J-C., Hacquemand, D., Moneglia, P., Pellegrini, H., Prodon, R., Recorbet, B., Seguin, J-F. and Villard, P. (2011). Distribution and population size of the Corsican Nuthatch Sitta whiteheadi. Bird Conservation International. 21(2): 199–206. Close ). In 1981–1984 c. 2000 pairs calculated, on basis of average density of 0·85 pairs/10 ha in c. 240 km² of suitable forest (3 Brichetti, P. and Di Capi, C. (1985). Distribution, population and breeding ecology of the Corsican Nuthatch, Sitta whiteheadi Sharpe. Riv. Ital. Orn. 55(1): 3-26. In English with Italian and French summary. Close ). These figures appear to represent marked decline from estimate of 3000 pairs in 438 km² of forest in late 1950s (4 Löhrl, H. (1961). Vergleichende Studien über Brutbiologie und Verhalten der Kleiber Sitta whiteheadi Sharpe und Sitta canadensis. [Part 2]. J. Orn. 102(2): 111-132. In German. Close ), although methodologies are not comparable (2 Thibault, J-C., Hacquemand, D., Moneglia, P., Pellegrini, H., Prodon, R., Recorbet, B., Seguin, J-F. and Villard, P. (2011). Distribution and population size of the Corsican Nuthatch Sitta whiteheadi. Bird Conservation International. 21(2): 199–206. Close ). Presence of old stands of Corsican pine (Pinus nigra laricio) appears to be key factor in survival of this species, and main factors limiting its abundance are fire (can destroy habitat for many decades), logging and removal of dead and rotting trees (used as nesting sites). It has been estimated that 78–122 territories have been destroyed by logging since 1998, and that a further 50–63 territories were lost during the large forest fires of 2000 and 2003, which severely affected another 47–80 territories (5 Thibault, J-C., Prodon, R. and Moneglia, P. (2004). Estimation de l’impact des incendies de l’été 2142142142 sur l’effectif d’un oiseau endémique menacé: la sittelle corse (Sitta whiteheadi). Ecologia Mediterranea. 30(2): 195-203. Close , 2 Thibault, J-C., Hacquemand, D., Moneglia, P., Pellegrini, H., Prodon, R., Recorbet, B., Seguin, J-F. and Villard, P. (2011). Distribution and population size of the Corsican Nuthatch Sitta whiteheadi. Bird Conservation International. 21(2): 199–206. Close ). Corsican Pine distribution is now fragmented, with a total >range restricted to less than 2·5% of the area of Corsica (2 Thibault, J-C., Hacquemand, D., Moneglia, P., Pellegrini, H., Prodon, R., Recorbet, B., Seguin, J-F. and Villard, P. (2011). Distribution and population size of the Corsican Nuthatch Sitta whiteheadi. Bird Conservation International. 21(2): 199–206. Close ). Its habitat is more likely threatened by an increasing frequency and intensity of wildfires and by logging than by climate change (6 Barbet-Massin, M. and Jiguet, .F (2011). Back from a predicted climatic extinction of an island endemic: a future for the Corsican Nuthatch. PLOS One. 6(3): e18228. doi:10.1371/journal.pone.0018228. Close ). Although large numbers of Great Spotted Woodpeckers (Dendrocopos major) can result in high predation of chicks, the woodpecker increases availability of suitable nest-sites. Species readily tolerates close proximity of houses, powerlines and traffic. Almost the entire global population of the species occurs within the Natural Regional Park of Corse (Corsica). This European endemic is considered Vulnerable at the regional level (7 BirdLife International (2015). European Red List of Birds. Office for Official Publications of the European Communities, Luxembourg. Close ). Prior to 2010 it was not considered of conservation concern BirdLife International (2015) Species factsheet: Sitta whiteheadi. Downloaded from http://www.birdlife.org on 03/08/2015. .