Commons can get quite white; this one from a couple of years ago:
- and of course male
flammea (Mealy) are frostier than females! (it would help when using reference photos to say when they were taken (also the ssp, sex and age of the individual if possible!)
Just for comparison . . .
commons.wikimedia.org
That’s actually a
hornemanni (Hornemann’s Arctic) I suspect, rather than an
exilipes (Hoary/Coues’s) so much whiter with spanking clean flanks and under tail coverts (utcs) (so an extreme comparison!) but
exilipes are much harder to separate, tend to exhibit heavier flank streaking and, females especially, have a small amount of streaking on the utcs. Also, immature/juvenile
exilipes can show moderate rump colour.
Some interesting pointers here PS note in particular the unreliability of using UTCs as diagnostic fearure, also note the extreme difficulty in separating 1st Winter Mealy from 1w Arctics (Coues’s/
exilipe)
You are not alone Chipster in struggling with Redpoll identification, they can confound the best and the rest of us!