HEMEL MEGAS: Possible SIBERIAN CHIFFCHAFF & SCANDINAVIAN CHIFFCHAFF between KLAS Kings Langley Fishery & Canal.

The Possible SIBERIAN CHIFFCHAFF (tristis) showed itself for a minute or so again this morning, between KLAS Kings Langley Fishery & the Grand Union Canal. I was alerted to it by its single call, a slightly squeaky, slightly down-slurred piping whistle. It spent a few seconds in branches overhanging the lake then flew up into the tops of the trees & bushes on the canal towpath until I could no longer find it. I managed to get a few more record shots, though the bird looks a bit darker in them due to being against a bright reflection in the water. The greyness on the nape is apparent & I noticed it seemed to have a small pale grey patch across its 'shoulder', as well as the supercillium (eye-stripe) looking obviously peachy-buff today. As the bird moves around its tones appear to change, looking brown above & white below one minute, then brown envelope above & milky tea below, then greyish tree bark above & pale peach below, but each time standing out as different to the other CHIFFCHAFFS on site, which there are C.3 of. Of the other Chiffchaffs, there is at least 1 definite 'normal' British-type Wintering CHIFFCHAFF (collybita) looking all dark green-brown, dusky below with dark cheeks & face with a slim yellow-green supercillium. Then there is the bird I got a view of today near to the 'Siberian', which was generally pale, dull greyish green-brown, with a pale throat & face but darker around the belly & under-tail coverts, & obvious but gently-yellowish supercillium. Its call sounded as a regular Chiffchaff, an upslurred quick 'huit' or 'whiip'. It had pretty pale bordered cheeks compared to that of collybita, but the lower eye-ring was more obvious against it than on the 'Siberian'. It's legs were reddish dark-brown rather than the jet black of the 'Siberian' & the bill definitely paler. In fact the general appearance of this bird was not dissimilar to a dull Willow Warbler, & I was surprised that the primary projection looked a bit longer than I was expecting on a Chiffchaff, with the gaps between tips being progressively larger nearer the wing-tip too, rather than even like a regular Chiffchaff. This bird has to be a SCANDINAVIAN CHIFFCHAFF (abietinus).

'Siberian'

Note buff flanks, white belly, light undertail coverts, buff supercillium, greyish nape & pale grey area on 'shoulder'.

Note buff flanks, white belly, light undertail coverts, greyish nape, pale grey area on 'shoulder', green in primaries, & jet black legs.

Note buff sides to breast, white belly, buff supercillium, greyish nape & pale grey area on 'shoulder'.

Note buff flanks, white belly, light undertail coverts, greyish nape, pale grey area on 'shoulder', & green in primaries.

Note buff flanks, white belly & light undertail coverts..

'Scandinavian'

Note pale face, pale cheeks with faint border, pale throat & lightish breast darkenish along flanks to sides of belly, obvious but soft supercillium & dull greyish green-brown colouring.

[Strip added to image to compansate for reed in foreground across bird's face]
Note pale face, pale cheeks with faint border, pale throat & lightish breast darkenish along flanks to sides of belly, but belly still paler in the centre, & dull greyish green-brown colouring.

Note pale face, pale cheeks, pale throat & lightish breast darkenish along flanks to sides of belly, obvious but soft supercillium & dull greyish green-brown colouring& dark red-brown legs.

Note dull greyish green-brown colouring & primaries more green than mantle.

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