Having had good views of the Veery, see here, we drove to Wester Quaff to see a rare Eastern Sub-alpine Warbler. The Sub-alpine Warbler complex is split into 3 separate species. The most commonly occurring UK vagrant is the Western Sub-alpine which breeds in Iberia, southern France, and northern Morocco. Next in terms of scarcity comes the Eastern Sub-alpine which breeds in Italy east to the coastal areas of the Adriatic. Finally the scarcest of the three, afforded a 3 start mega status in the Colins bird bible, is the Moltoni’s Warbler which breeds on mainland Italy, Corsica, and Sardinia. All three winter in Western Africa. Somewhat strangely, the only one of the three I have previously seen is Moltoni’s so the Eastern would be a UK life tick for me.
The bird was in typical Shetland warbler habitat, a small garden of mainly stunted sycamores. These trees had not yet shed their leaves making warbler observations very problematic. I would say they are not intrinsically particularly shy or skittish but the nature of their feeding habit, restlessly moving through the trees searching for insects, tends to yield very brief and frustrating glimpses. Part of the trick here is to realise that these warblers tend to have a feeding circuit so, rather than chase them round like something from a Keystone Cops film of old, its best to pick a good spot somewhere on the feeding circuit and wait patiently. We were hence eventually rewarded with some moderately good views of this dainty bird. It was a first winter bird, i.e. hatched this spring, and as such lacked the attractive slate grey and rusty orange tones of the adult.
The adult eastern subalpine warbler differs from its western cousin by its deeper blue-grey upperparts, a blackish mask on the lores and ear-coverts, brick reddish-brown coloration confined to the throat and breast and sharply demarcated from a largely white belly, paler flanks and a wider white sub-moustachial stripe The first winter Eastern is an altogether duller and toned down bird displaying mainly grey and buff tones. The first winter eastern is only separable from the western by its tail pattern and call. Here we are relying on other birders who heard the call to tie it down.
We watched it on a further two or three of its feeding circuits before moving on. What a way to start Shetland 2023, two rare new lifers on the first morning, surely it can only go downhill from here?
Footnote - My blogs are posted with sometimes rather imaginative spelling and grammar due to my extreme dyslexia!
Very nice!
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