A couple of days ago we noticed this yellowhammer feeding on the grain in our front garden. Throughout this winter we've had large numbers of yellowhammers visiting us, up to half a dozen at any one time. It isn't a bird one would expect in a place like this - we associate them with the large, open arable fields of East Anglia.
This male seems to have some sort of additional growth of feathers low down on his right breast.
It doesn't seem to bother him in any way - for example, he flies perfectly well, and he has as good an appetite as all the rest of them.
Has anyone seen anything like this before, and can anyone explain it?