Originally Posted by Howard King
Hi Hannu -
Swensson (in my english copy page 178) also states for H. pallida, the following:
NB.1 The smallest individuals of H. p. elaeica may be difficult to separate from H caligata Booted Warbler –
NB. 2 H. P. elaeica may also be very difficult to seperate from ad. Acrocephalus dumetorum Blyth's Reed Warbler.
You mention that head shape and size as being wrong for Booted it is precisely these features that many birders here in the middle east, feel do not fit into their perceived jizz for Olivaceous or Upcher's they state that those species are much more flat headed. I however still remain open minded and await a clinical diagnosis of the pictures. I now change my mind yet again to "don't Know"
We do also face a problem with Swensson for some species - a lack of data so we have to use a variety of other books. The reason being that in the Arabian Gulf so few birds have been fully studied or collected that the sub species thought to occur for some has to yet to be proven scientifically and could in fact be wrong. In fact so much of the old data we have here is based purely on field obs, separation for many Ssp can be dificult enough even with the bird in the hand. We are fortunate to be able to call on Mike Jennings coordinator of Arabian Breeding Bird Atlas he has an incredible database and bibliography plus a wealth of local birding expertise.
At least some EOW can be that kind of head shape in some pics.
The size is sometimes rather difficult to estimate in the field and the variation of the size is rather big on these small sized birds (very often 10%).
I wonder why the bird seems to be some tail movements in the pics, which just refers to EOW or Upcher's.
We can rule out Blyth's Reed for sure. Blyth's Reed has chest-nut iris and curved rictal bristles, whereas all Hippo species have relative dark eye and straigth rictal bristles. Also Blyth's Reed has same colour in alula as the wing. This is somewhat variable in worn birds in BRW, but most have outer web
of alula quite uniform and contrasting to darker inner web
. Marsh Warbler, Eurasian Reed Warbler and at least most greyish Hippo species have darker alula with paler outer margin