Dispersal

I was delighted to get good views of this little bird in the plum tree today. It was very mobile, but stayed a while and posed from time to time. I think it's a aWillow Warbler, but I'm willing to be challenged, as without the song I never feel sure.
As these visits seem to be an annual occurrence from now onwards, I imagine breeding has finished and the birds are now dispersing. They take advantage of the greenfly which are  in abundance here.