Willow Warbler - 36

I have identified this as a willow warbler but if anyone could help out I would be grateful. I've included an extra, where the head is obscured but it may help someone with identification. 

The main shot was complete luck because I knew the bird was in the ferns somewhere and was amazed when I went through the pictures I took to see it was vaguely in focus. Its not ideal but much better than expected.

If if is additional help it was in an area of ferns in the forest with pine and birch trees and close to a boggy area. Im not very good at identifying bird song but I don't think it was a chiffchaff which was the most obvious alternative.