the white goose

I may have found the name of the white goose that has been hanging tight with my Canada Geese for a few weeks now. This goose breeds in northern Canada, mainly in the Queen Maud Gulf Migratory Bird Sanctuary, and winters much further south in the continent in the southern United States and occasionally northern Mexico.
The plumage of this species is white except for black wing tips. It is similar in appearance to a white-phase snow goose but approximately 40% smaller. Other differences from the snow goose are that the bill is smaller in proportion to its body and lacks "black lips". The dark phase is extremely rare.
The Ross's goose is a rare vagrant to Western Europe, but it is commonly kept in wildfowl collections and so the true frequency of wild birds is hard to ascertain. Escaped or feral specimens are encountered frequently, usually in the company of other feral geese such as Canada Geese.
Or this is a Snow Goose that has lost his way. Th described features match the Snow Goose more than Ross's Goose. What do you think?

FEB 28, 2018 ​I went to check on my goose friends this morning and discovered a white goose. He/she is not a Canada goose in the color and size and he/she never honked either. When the two accompanying Canada geese took flight he/she did too. A few minutes later they did a fly by and had added a fourth to the group. The island geese are pairing off now. And building/rebuilding nest. The yearlings, parents and other family members are on their own until we have goslings running about.