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 because they look almost identical from the air. It was estimated that the greater scaup made up about 11% of the continental scaup population. Since the 1980s, scaup populations have been steadily decreasing. Some of the primary factors contributing to this decline are habitat loss, contaminants, changes in breeding habitat, and a lower female survival rate. The 2010 American scaup population survey was 4.2 million scaup, however, the worldwide greater scaup population survey estimated 1,200,000 to 1,400,000 mature greater scaup. Along with the aerial population surveys, there is a banding program for the greater scaup. Metal leg bands are placed