Hey, I saw this little fella maybe ten days ago on a southern island in Baltic Sea in Finland and have troubles to ID it. When I saw it i thought it could be phylloscopus - probably a chiffchaff but then somebody told be it could be an acros species. Also all the pictures of chiffchaffs I've watched I dont really get a match to this one. It was a short moment and these are the only photos I got. And one thing with the beahaviour, I saw it dipping the tail downwards a few times, makes me also think of chiffchaff but Pallida does it also. What do you think?