Putative Desert Lesser Whitethroat Sylvia curruca minula / halimodendri
Wells East Hills, 3/11/08
Ok, it's a bit of a cliché - find a Lesserthroat in November and you've got to call it an 'Eastern'. Over the years, we've seen our fair share of late autumn birds that look a bit funny (and plenty that look like bog-standard locals), but this one was definitely in a different class. And although we normally try to avoid getting sucked into over-Garnerization, our general lack of rare-finds this autumn has got us clutching at straws...
The bird was strikingly pale sandy above and dull buffy below, lacking contrast (almost monotone away from the throat). But most prominent was the structure / size - it was small, dumpy and very long-tailed. Overall shape and jizz/actions recalled Sardinian more than Lesser Whitethroat...!
Obviously the primary projection is very short and the wing rather blunt, but the length and narrowness of the tail was even more striking. It was so long it actually wobbled when the bird flew, like a Bearded Tit...!
It constantly held the tail cocked a la Sardinian, showing off some broad white outer webs. Supposedly, excess white in the outertail is indicative of minula over halimodendri (maybe)...?
Plumage tones on the upperparts were sandy / pale in good light, but appeared a more rich buff-brown in shadow. Perhaps most importantly, there was very little contrast anywhere except the forecrown and ear coverts. Note how the buff-brown tones extend right up the nape and onto the crown (areas that would be greyer on western Lesserthroat). At most angles the ear coverts also looked similar in tone to the crown and mantle, with darker grey tones only appearing at certain postures.
I've occasionally seen similar mantle tones to this bird on 'standard' autumn Lesserthroats, but they have always been combined with both grey crown and gleaming white underparts. This bird had distinctly sandy-buff tones to the entire underparts away from the throat. The bill was rather weak, with a pinkish hue to the basal portion.
Size - good comparison next to this blackcap. It seemed to be at the small end of the scale for Lesser Whitethroat - probably exaggerated by the short wings and long, thin tail.
It only called twice during about two hours of observation - seemingly a little bit softer and more slurred than normal Lesser Whitethroat, a quiet "trk". It was also briefly heard to give a distinctly rattling "trrrr", more remeniscient of Spectacled Warbler.
In conclusion - Lesser Whitethroats are a nightmare, Svennson says 'don't do it', but this was definitely an unusual bird. It's got to be from somewhere far east, but precisely what subspecies is hard to say. Fashion seems to be to stick UK records like this into the amorphous halimodendri group. If it is a halimodendri, it is presumably from the far end of the range where it intergrades with minula, as it is very different from those normal-shaped dark brownish blythii types we've seen on Shetland. Opinions welcome, particularly from anyone with experience of autumn minula and halmodendri within range.