Friday, 27 August 2021
Thursday, 26 August 2021
13-8-2021 PARQUE DE JESUITAS, SALAMANCA - WILLOW WARBLER (Phylloscopus trochilus)
The willow warbler was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Motacilla trochilus. The willow warbler is now one of around 80 species placed in the genus Phylloscopus that was introduced by the German zoologist Friedrich Boie in 1826. The genus name combines the Ancient Greek phullon meaning "leaf" and skopos meaning "seeker" (from skopeo, "to watch"). The specific epithet is Ancient Greek meaning "wren".
Before the English name was standardised to willow warbler by William Yarrell in 1843, it was sometimes called "willow wren".
Three subspecies are recognised. There is a clinal reduction in green and yellow plumage tones from west to east, with central birds browner and easternmost birds predominantly greyish:
P. t. trochilus (Linnaeus, 1758). Breeds Europe (from the Pyrenees and Alps northward) except northern Scandinavia, winters west Africa.
P. t. acredula (Linnaeus, 1758). Breeds northern Scandinavia east to western Siberia, winters central Africa.
P. t. yakutensis (Ticehurst, 1935). Breeds eastern Siberia, winters eastern and southern Africa.
The willow warbler is a typical leaf warbler in appearance, 11–12.5 cm (4.3–4.9 in) long and 7–15 g (0.25–0.53 oz) weight. It is greenish brown above and off-white to yellowish below; the wings are plain greenish-brown with no wingbars. Juveniles are yellower below than adults. It is very similar to the chiffchaff, but non-singing birds can be distinguished from that species by their paler pinkish-yellow legs (dark brown to blackish in chiffchaff), longer paler bill, more elegant shape and longer primary projection (wingtip). Its song is a simple repetitive descending whistle, while the contact call is a disyllabic 'hoo-eet', distinct from the more monosyllabic 'hweet' of chiffchaffs.
All populations are highly migratory, with the subspecies P. t. yakutensis migrating up to 12,000 km (7,500 mi) from eastern Siberia to southern Africa along the Asian–East African Flyway, one of the longest migrations of any for a bird of its size. Approximate timings are:
October to March: wintering in sub-Saharan Africa.
Mid-March to mid-May: migrates and arrives in the breeding range.
Late April to August: breeding season, usually only one brood but rarely two.
August to October: migrates back to Africa.
Wednesday, 25 August 2021
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