Thanks to John Bridges for allowing me to use his images, all photos below Copyright © John Bridges UNLESS otherwise stated.
(What a beauty! Note the over all paleness of the bird making it look very white. Only one flank streak visible and very fine, if any flank streaking is present then it is very fine as it can't be seen on these images. Also note the all important large white rump, you can see from this image the rump is extensive extending a good way up the birds back. Having seen this bird myself I can confirm that it is a very large and unmarked white rump. Definitely the safest feature that points toward Arctic Redpoll.)
(Note: How appearance can alter depending upon what the bird is doing, here the birds head shape and the way the bird is holding its head makes the bill look large. In actual fact in the field this birds bill is very short and pushed in.)
(Note: Click on the image to increase its size, you can see on the under-tail coverts (the bit before the tail starts) only 1 very thin black streak. This is typical of Coues' Arctic Redpoll, most typical birds should show only 1 dark think streak like this bird. OR no streaks at all. Though some birds can have varying under tail covert streaking so this feature alone is not so good to go off for positively ID'ing Arctic Redpoll of any race.)
(Finally note again the paleness of the bird, its very white and pale even compared to the pale Mealy (bottom left). The Lesser Redpoll (top right) can be separated easily here. Note the overall dull brown tone of the entire bird making the bird appear very brown and fairly uniform. The Lesser Redoll here can also be easily told from the Mealy Redpoll (top left), the Mealy is much paler and whiter overall, also it is slightly larger and this can easily be seen in this photo. Though it is sometimes hard to assess on individual photos or in field conditions where birds may be distant.)
Here's a picture by Derek Charlton of the same bird back end on:
(Coues' Arctic Redpoll - © Derek Charlton)
(Do I even need to say "note: the smacking great big white snowball of a rump". But also note the very fine flank streaking that can be seen. This bird is the one the field guides want you to see! Nice and easy. :) )
Until next time, Foghorn out!