Ha! Having said the Clifford Hill Black-necked Grebe looks like it might be a moulting adult, I had closer views in better light late this afternoon and clearly I was wrong. It’s a juvenile with a considerable brown suffusion to the upperparts and neck, the latter with a faded, almost broken front. Just goes to show that photographs can be deceptive with regard to assessing true colour tones and extent!
Black-necked Grebe: postscript
Northants birds 