Anse de Saint-Vallier is a small bay on the south shore of the St. Lawrence River by the village of St. Vallier, Québec. It consists primarily of a mudflat and a Scirpus marsh; the area’s boundaries are delineated by the high and low tide levels. The Boyer River, which flows into the bay, is a spawning site for three species of fish at risk.
Anse de Saint-Vallier is noteworthy for its flocks of migrating waterfowl. The most prominent of these is the Greater Snow Goose (subspecies atlanticus), which can be present in globally significant numbers in the spring. In 1995, a flock of 50,000 were spotted, accounting for over 1% of the global population of this subspecies.
Numerous other waterfowl species, including Canada Goose, are common at the site, especially in fall when hunting pressures elsewhere bring them here for shelter. At this time, surveys have recorded both species of scaup, with maximum counts of 2,510 for Greater (1975) and 4,000 for Lesser (1988).
This site also hosts flocks of migrant shorebirds in spring and fall. The most common species are Killdeer, Black-bellied Plover, Spotted Sandpiper, Greater and Lesser yellowlegs, and White-rumped, Least and Semipalmated sandpiper. The highest numbers are found in early August. For instance, in August 1989, a peak of 4,000 Semipalmated Sandpiper were recorded.
Conservation responses/actions for key biodiversity
The St. Lawrence seaway is a heavily travelled route, making the risk of oil spills constant. Toxic substances found in the area come from three major sources: the waters of the river and its tributaries, industrial waste, and municipally-used waters. Two industrial plants situated upstream from Saint-Vallier have been designated as major sources of pollutants by the Priority Intervention Area committee. Heavy metals are the main known toxins and attach to suspended material in the river but, since sediments don’t stay long in the Orléans Island channel, the contamination level is not known. There are agricultural fields along the Boyer River that, in turn, could be another pollution source.