ML646378087

観察結果の詳細

Among a flock of 18 Greater White-fronted Geese there were two birds that stood out as clearly different in size bill length and pattern. The two birds appeared to be about 5-10 % larger in side-by-side comparison with the expected "Western" Greater White-fronted Geese. Their most distinctive feature was their generally darker overall plumage, especially the upper neck and head, which were fairly uniform dark chocolate brown with less light to dark contrast in the face. In profile, they clearly had more elongated and flatter-sloped bills and their bills were larger than those of the "Westerns". Everything about the size, bill length and coloration of these two individuals was consistent with "Tule" Greater White-fronted Goose, a somewhat rare but regular migrant through Oregon. Photos.