It's one of the red-necked parakeets that have have become a naturalised British species, of course, the first time I've managed to get a photo. I saw three more or less simultaneously, this was the only one that landed where I could get a picture, the others vanished into the leaves. Since I could only see it as a blob in the viewfinder I wasn't able to get a better picture; this is the clearest, and none of the others show its head any better.
