One for Seymour

Question

Hi Seymour 
 Have you got another 'puzzler' for us? I learn so much from having to think about identification and study detail of birds' features. 
 No problem if you are very busy. 
 I hope you are feeling better now. 
 Cheers 
 Pipit x

aiki · Accepted Answer

Right. The genus clue actually rules out Cetti's - Sylviidae is the family but Lesser Whitethroat is in genus Sylvia, with much fewer UK candidates :) 
 Besides that, the angle makes it tricky to see wing and tail length clearly, but Cetti's has a super-short primary projection, and this mystery bird's primary tips are clearly long enough to easily cross over each other (this bird has long wings because it is a long-range migrant, while Cetti's is sedentary). Also Cetti's has a stronger face pattern with a pale supercilium extending a little way behind the eye and, yep, paler legs. 
 That leaves the mystery bird as a Garden Warbler, with its beady eye in a very plain face and subtle grey neck-sides. So Pipit and Blackbird both got it right :) 
 I pronouce Cetti's 'CHETT-ies' :)