Ross's Goose Overview, All About Birds, Cornell Lab of Ornithology

Downy young come in two colors: yellow and gray. The two forms look identical once they get real feathers.

Very rarely a Ross's Goose can be found that is dark-colored like a blue morph Snow Goose. These blue morph Ross's Geese are thought to be the result of hybridization with Snow Geese.

Prior to the 1950s the Ross's Goose was confined to well-defined breeding and wintering areas, with few seen as strays. Since that time the species has been expanding eastward, both on the breeding and wintering grounds. The change in breeding distribution has resulted in more contact and subsequent hybridization with the Snow Goose.

The female Ross's Goose does all of the incubation of the eggs. The male stays nearby and guards her the whole time. The female covers the eggs with down when she leaves the nest. The down keeps the eggs warm while she is away and may help hide them from predators.

The oldest known Ross's Goose was a female, and at least 22 years, 6 months old when she was shot in California in 1993. She had been banded in 1972 in Saskatchewan.