Male Snow Bunting?

[Dinusaur]

When I went to see Smith's Longspur in Long Point, I photographed a flock of snow buntings in flight. One or two in every flock seem different because of the large white patches on the black wings. The picture below shows one that is different from the other three. Is it a male Snow Bunting? Or is it difficult to tell - the variation may be because of different stages of molting? Thanks in advance.

[thouc]

Yes, the ones with brighter black and white wings are adult males.