Tundra Bean Goose

The taxon Bean Goose has evolved a lot. Originally, it grouped in subspecies all of the morphs showing approximately the same characteristics, a black and orange (or pink for one of them) beak and orange legs. After quite a few mishaps, the current situation is as follows. The taxon gave birth to 3 species, Bean Goose itself, Tundra Bean Goose and the Greylag Goose. Here we will focus on the second one, Anser serrirostris. This one has two subspecies, the rossicus in the west and the nominative serrirostris in the east.
The Tundra Bean Goose of the rossicus subspecies is close in appearance to the western subspecies fabalis of Bean Goose, and the distinction is not obvious, especially with single individuals. Moreover, the two taxons can winter side by side. They have approximately the same size but the appearance is slightly different. In rossicus, the head-neck area is of a dark brown which contrasts better with the rest of the plumage. The neck is slightly shorter and the beak too, and more stocky. The beak is particularly important. It is high at the base and relatively short, triangular looking from the profile. It has a straight culmen, rarely very slightly convex. It is black with just a fairly narrow orange subterminal ring, yet even some fabalis have this too. It is therefore the beak's morphology which is decisive. Sometimes, a bit of white marks the outline of the beak base. The eye is dark and the legs are bright orange. The sexes are similar.
In the juvenile, the beak ring is indistinct and the legs are dull.