©
Gregg Thompson
The "Blue Goose" was considered a separate species until 1983, when it was recognized as one of two color morphs of the Snow Goose. Whether or not a Snow Goose is dark or light is decided by a single gene, with dark being slightly dominant over light1. Most "Blue" Snow Geese are found in the center of North America during migration, but this one was photographed in Washington State.
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