Nicolet Bird Sanctuary During the spring migration, there were nearly 500,000 snow goose ("Chen caerulescens"), or nearly all of the population of species "atlantica". It is also an important site for the migration of Canada (Branta canadensis), where more than 100,000 individuals were observed in 1998. There are also a number ("Black duck") ("Anas rubripes") and of black scoter ("Melanitta nigra"). During the autumn, there are a significant number of pintail ("Anas acuta"), small scaup ("Aythya affinis"), Scaup and golden-eye withered ("Bucephala clangula"). Ducks nesting on the site are the Aix sponsa, the nasal duck, Anas clypeata, the gill duck, Anas strepera), 'American
Lesser scaup where the white extends to the eye region. But especially with juveniles, the bi-colored bill of hybrids is most diagnostic. Hybrid combinations that are known from the wild and resemble the lesser scaup are: In theory, each and every "Aythya" species is able to produce potentially fertile hybrids with any other, though due to their different ranges and behavioral cues given during courtship most of these hybrids are only known from birds kept in captivity without conspecific mates. Their breeding habitat is inland lakes and marsh ponds in tundra from Alaska through western Canada to western Montana; few breed east