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Вот на днях такая трясогузка попалась нашему фотографу Voodison-у (нынче Владимир Кучеренко). Кольцо не наше, но явно украинское, серия «В».
Какой подвид? Или гибрид?
(25.04.2009. окрестности Одессы) |
Я имел переписку с Ларсом Свенсоном по этому вопросу. Вот что он мне писал о черноголовых трясогузках с белыми и желтыми бровями:
You also had a question to me. According to what is known from the literature Motacilla flava 'superciliaris' is a hybrid occurring where feldegg meets with flava, beema or cinereocapilla. So old master Edward Gavrilov is right. Judging from the varied localities where 'superciliaris' has been seen or collected it is not a proper subspecies; it does not seem to be exclusive in breeding season in a defined area, which is the requirement for a valid geographical race. Therefore it is best regarded as hybrid or intergrade between feldegg and any of the mentioned taxa. Ssp. lutea may be involved as well. Whereas 'superciliaris' has a black head and a white supercilium, there are other variants as well. Those with largely yellow supercilium on a black or blackish head are usually called 'xanthophrys' (and could have lutea genes!). There is yet another named variant, but which hardly concerns Kazakhstan. I attach an extract from my text about the Yellow Wagtail for the forthcoming Photographic Handbook I am writing together with Hadoram Shirihai. M. f. feldegg (SE Europe, Asia Minor, Caucasus, Near East to Caspian Sea, N Iran, S Kazakhstan), ‘Black-headed Wagtail’, is generally quite distinct with black cap and no white supercilium, the black crown being glossy before too worn. The black cap reaches often far down at the rear, onto upper mantle, and is distinctly marked against the bright greenish rest of mantle. (Birds with diffuse border are probably hybrids with neighbouring paler-headed race.) Black of head in fresh plumage may have some (yellowish-)green tips admixed (never any blue-grey, which is indicative of
thunbergi). Underparts incl. throat is deep yellow. Normally no white on chin or sides of throat, these being deep yellow. Lacks dark blotches across upper breast (as are so common in
thunbergi). Birds E of Caspian Sea (‘
melanogrisea’) tend to have less extensive and less glossy black cap, and often have a little white on chin and sides of throat, although much overlap, and characters form a stepless cline, hence not recognised as a separate race.
oo varies extensively, many being distinctive with blackish cap, greyish-tinged upperparts and off-white underparts (faintly yellow only on belly, vent and un.tail-c.), others having more yellow below and greenish tinge on grey-brown back, and a partial pale supercilium. Throat nearly always whitish as in
cinereocapilla. No whitish mark below eye. Lores rather plain, uniformly dark (black or slate-grey) or fairly pale grey-brown, lacking dark narrow streak under pale supercilium as in most other races. Call invariably a harsh
tsreep or
tzree(
eh) with audible ‘r’ in.
W a 82–89 mm (
n 17,
m 84.2),
o 75–84 mm (
n 15,
m 80.0);
T a 69–74 mm (
n 17,
m 71.8),
o 67–74 mm (
n 15,
m 69.6);
T/W m 86.1;
B a 15.6–17.5 mm (
n 17,
m 16.7),
o 15.0–16.5 mm (
n 14,
m 15.8);
TS 22.2–25.2 mm (
n 32,
m 23.6).
Wing formula: p5 < wingtip 3–6 mm,
p6 < wingtip 9–13.5 mm;
p10 < wingtip 22–26 mm;
s1 < wingtip 23.5–28 mm. (Syn.
melanocephala,
melanogrisea.) – Hybridises with
flava,
cinereocapilla,
beema and
lutea in zones of contact, and resulting mixed populations can attain striking appearances, and have received formal names, although we regard them as too instable and heterogeneous to be recognised as subspecies, also since exclusive breeding ranges are lacking or at least are unknown:
‘superciliaris’ has a black cap and a white supercilium;
‘xanthophrys’ is similar but has a yellow supercilium;
‘dombrowskii’ resembles
flava but has blackish ear-c. without a white mark under eye, and has darker grey crown and nape.
Cheers, Lars
