Diversity, abundance and distribution of aquatic birds wintering in the coastal and pelagic waters of the Saguenay–St. Lawrence Marine Park
The Saguenay–St. Lawrence Marine Park (PMSSL) is located in one of the most productive areas of the St. Lawrence and supports large numbers of aquatic birds all year round. Nevertheless, there is no detailed study on the use of this area by aquatic birds in winter. So, to rectify the situation, aerial and ground surveys were done to better quantify the distribution, abundance and behaviour of aquatic birds wintering in the PMSSL. Results confirm the importance of the PMSSL for aquatic birds wintering in the St. Lawrence estuary, and establish that birds move within the PMSSL in relation to tides, ice conditions and winds. The most numerous waterfowl species are the Long-tailed Duck (Clangula hyemalis), the Red-breasted Merganser (Mergus serrator), the Common Goldeneye (Bucephala clangula), the Barrow’s Goldeneye (B. islandica) and the Black Duck (Anas rubripes). Four species of gulls winter there in great numbers: the Arctic Gull (Larus glaucoides), the Glaucous Gull (L. hyperboreus), the Herring Gull (L. argentatus) and the Great Black-backed Gull (L. marinus). Black Guillemots (Cepphus grylle) were also present offshore, as well as Purple Sandpipers (Calidris maritima) on the offshore islands and shoals, and a small number of Buffleheads (Bucephala albeola). Christmas Bird Count Data suggest an increase in wintering populations of Black Ducks, Mallards (Anas plathyrynchos), Barrow’s Goldeneyes and Red-breasted Mergansers. However, large flocks of Long-tailed Ducks have been less frequent in recent years.