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
Greater scaup molluscs, aquatic plants, and aquatic insects. During the summer months, the greater scaup will eat small aquatic crustaceans. There is a report of four greater scaups in April near Chicago swallowing hibernating leopard frogs (with body length about ), which they dredged out of a roadside freshwater pond. In freshwater ecosystems, the greater scaup will eat seeds, leaves, stems and roots, along with sedges, pondweeds, muskgrass, and wild celery. Owing to the greater scaup's webbed feet and weight, it can dive up to and stay submerged for up to a minute, allowing it to reach food sources that are unobtainable