Cackling Goose Branta hutchinsii
These two were in a flock with 6 Canada Geese. They are best identified first by smaller size, usually when flying. When still on the ground with Canada Geese the size difference can be seen. The white necklace is distinctive when present. The smaller bill size can sometimes be seen, though the largest Cackling bill sizes can resemble the smallest Canada bill sizes.
necklace visible. Next photo - Cackling on left, two Canada on right
6 February 2024 Arvada, Colorado