On 11/15/09 in a flooded field south of Parker, AZ this completely white gull flew into a field full of over 100 other gulls. The conclusion I came to was that this bird is either an albino or leucistic (lacking any pigment including melanin) Ring-billed Gull. Below are 5 pictures of various poses that help support the description that follows:
EYES: Although the exact color of the eyes wasn't seen, the fact they were pale was noted...the pupil was clearly visible at a distance. It could have either been yellow or pink?
LEGS: colored pink
BILL: a similar pink to the legs with a pale tip and black sub-terminal band near the end.
BEHAVIOR: acted exactly like the other Ring-billed Gulls in close proximity.
PLUMAGE: after a while under certain light some darker (only a slight shade) smudges were noted on the ends of the retrices (tail feathers). Also, under certain light, the mantle appeared a SLIGHT shade darker.
1) side by side with a 'normal' plumaged Ring-billed Gull
Your comments are welcome. This was a great bird to see and a fun study in using other clues aside from plumage coloration to aid in identification.