Sunday, 18 November 2012

was it or wasn't it a spinoletta pipit?

well, in the end, no seems the blunt answer! As was kindly pointed out by Jan on brighton and facbook birders, this bird seems more likely to be a Scandinavian Rock Pipit- anthus petrosus littoralis. I've tried to collate some reasons for this conclusion below;

Suitable for?
Quite long, pale lower mandible, bird given quite a ‘worried’ expression
possibly Scandi or water pipit, resident petrosus in this area have a shorter, slightly more pointed bill(similar to Meadow Pipit), resulting in a sharper facial expression- though I’m not sure how reliable this is as a feature and certainly wouldn't advise it as a good method of separation
Very faint, kinks up slightly behind the eye but didn’t look very strong 
Seems to be more typical of petrosus, I have seen some petrosus locally with stronger super’s than this bird showed, though littoralis can have a weak supercilium. Seems to rule out Water Pipit
Bold white eyering
Probably very variable, best discounted- bolder than any petrosus present but as that was only five individuals, that's not saying a lot!
Moustachial stripe
Present but faint, not very easily discernible due to distance from bird, flat light and the way it typically posed
Seems a pro littoralis feature to me
Head  colouration
Neutral greyish brown, very little discernible streaking (consider flat light though)
Pro littoralis, lacking the olivey tones of petrosus
Pale, obvious white ‘triangle’ under bill, defined by presence of moustachial strikes
I think any of the pipits can show a pale throat
Quite heavy, blunt streaking, but streaks are well defined and cut off about halfway down the breast. Overall paler, creamy-white tone to breast
Pro littoralis, petrosus should show more suffuse, smudgy streaking and have a more olivey tone to the breast. Heavy streaking another sign that seems to rule out a Water Pipit
Quite ‘clear’ looking, creamy colouration but with more smudgy grey streaks than on breast
Smudgy grey streaks could be a feature for petrosus or (some) littoralis, but to reiterate what I said above, creamy colouration rather than olivey seems pro littoralis
dull greyish-brown, heavily streaked
Pro littoralis, a stronger, olivey tone is generally found on petrosus
Pale fringing to median and greater coverts, creating strong double wing bar
a stand-out feature compared to any resident petrosus I’ve seen in East Sussex, though this is quite a subjective feature to judge
Whiteish outer tail feathers, a la Meadow Pipit
Pro spinolleta or littoralis, it would be difficult to judge well enough to separate the two based on the views I got, but other factors seem to rule out Spinoletta thoroughly.
Could apply to any of the pipits as far as I’m concerned
Upright and wagtail-like, a line drawn from head to tail, when seen side-on and standing, would be at about a 60° angle to the ground
Posture has often been a useful way for me to pick out Spinoletta or littoralis, Petrosus  in my experience seems to have a more ‘crouching’ posture, if you were to draw the same line on a petrosus in it’s normal posture, it would come to about 45°, a noticeable difference

it did cast a more petrosus-like jizz in some photos, like this one where it appears
olive-tinged and short-billed, this wasn't quite how I remembered the bird in the
field however.

In the end, I feel confident enough to say I think was one, albeit not an atypical littoralis when concerning the strength of the supercilium. At some point it would be good to go and have another look, maybe in better light- perhaps my task for next weekend? definitely an interesting bird at any rate, and I'd appreciate any opinions you may have!!


Liam :) 

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