It is time for another installment in the constant effort to separate Lesser Canada Goose (Branta canadensis parvipes) from Taverner’s Cackling Goose (Branta hutchinsii taverneri). The two species overlap in size and coloring, but structural differences are often apparent to those of us nerdy enough to study lawns covered in geese.
Here are two Western Canada Geese (B. c. moffitti) and a Lesser Canada Goose. They are nearly identical in color and shape, but the Lesser is about 2/3 the size of the Western. This is your best clue to identifying Lessers.
Without the size comparison, you might be hard pressed to distinguish this Lesser Canada from a Western. The neck is long and thin. The bill and forehead form a smooth, gentle slope.
Compare these Taverner’s to the Lesser. On a Taverner’s Cackling Goose, the neck appears thicker and often shorter. The forehead forms a noticeable bump where it meets the bill. (This causes the bill to appear stubby, but there actually isn’t much difference in the bill shape between the two species.) The breast on Taverner’s is often lighter in color than that of Lesser Canada, but both species show a lot of individual variation.