Baie des Escoumins et Grandes-Bergeronnes (QC084)
Les Escoumins, Québec
Altitude 0 - 3m
This site stretches along the north shore of the St. Lawrence River, from the village of Grandes Bergeronnes to the mudflats just past Les Escoumins at Pointe du Moulin. The shore is generally rocky except at Baie des Escoumins, where there are extensive mudflats that up to a kilometre wide during very low tides. Several small islands are situated close to Les Escoumins. They include Ilets Boisés, and Petite and Grande Caye à Brisson. The Rochers Bare and Ilot des Bergeronnes are farther to the west. Four ‘at risk' species of whales frequent these waters.
This site hosts congregations of many waterbirds. Seven species have been reported in significant numbers. Brant migrate through the area in large numbers during spring migration, with a maximum count of 5,500 birds recorded in 1986. This is 4% of the Atlantic bernicla population or over 1% of the North American population. Three species of duck congregate here in significant numbers in different seasons. American Black Ducks can be present in globally significant numbers. Up to 5,000 have been seen in the fall, and 3,200 in the winter - both numbers are over 1% of their total population. Barrow's Goldeneyes are sometimes seen in continentally significant numbers, such in the winter of 1978 when 60 were counted (almost 2% of the eastern population). Although small numbers of Common Eiders (subspecies dresseri) breed on the Rochers Bare, much larger numbers have been recorded in the area in the summer. In July 1996, 2,500 birds or 2% of the dresseri population were counted.
This location hosts up to 10,000 gulls in the fall. A large proportion of these birds are Herring Gulls, for instance in 1980, 8,000 Herring Gulls were recorded (about 3% of the North American population), and it is one of the best sites in Quebec to witness fall migrations of Bonaparte's Gull. In winter up to 1,250 Iceland Gulls (6% of the global population) and 300 Glaucous Gulls have been recorded (1.5% of the North American population).
Fall shorebirds are common in the Baie des Escoumins; the most regularly seen are Sanderling (500 in 1978), Semipalmated Sandpiper (300 in 1979), Semipalmated Plover (300 in 1996), Black-bellied Plover (100 in 1985) and Least Sandpiper (100 in 1977).
A few thousand Canada Geese and Snow Geese are usually seen in the spring, and Common Goldeneyes, Oldsquaws and Surf Scoters, are common along this piece of coast in various seasons. Finally, in addition to the eiders, five other species breed in the Baie des Escoumins in small numbers – these are Great Black-backed Gull, Black-legged Kittiwake, Double-crested Cormorant, Great Blue Heron and Black-crowned Night-Heron. In 1995, 823 pairs of Herring Gulls were counted in several variably-sized colonies.
The western portion of the IBA is within the Saguenay-St. Lawrence Marine Park and the Baie des Escoumins is located outside the park. Risk from oil spills is concerning because of the numerous ships and tankers using the St. Lawrence Seaway. Such a disaster would have a catastrophic effect on the populations of aquatic birds. Note - contaminated sediments were reported in the IBA but an environmental impact assessment study has not been undertaken. The municipality of Les Bergeronnes is still dumping untreated sewage into the river, which is another source of pollution for the area between the river mouth and Pointe à John.
In 2013, the wharf was completely repaired and there was no apparent impact on the duck populations. Nonetheless, ducks were using the opposite shore of the river during the reparation work. Similarly, the destruction of the Escoumins River dam had no significant effect on birds.
The landscape of the area is typified by salt marshes, intertidal rocky shore, mudflats, river's estuaries and long sandy beaches. The mixing of the cold and well-oxygenated waters with the warmer waters of the St. Lawrence favors an unusual marine biodiversity. Several marine species are commercially exploited, such as the common whelk, the soft-shell clam, the green sea urchins, the Stimpson's surf clams, the snow crab and the Atlantic herring. Moreover, the harvest of soft-shell clam at low tide is a popular recreational activity throughout the region of Lower North Shore. The north shore of the estuary is also hosting a variety of pelagic species occupying an important role in the food chain, such as the capelin and the rainbow smelt are also targeted by the sport fishermen.
The fish habitat is affected by coastal erosion, residential development, harnessing of rivers and the creation of resorts. In addition, the presence of industries discharging pollutants in the system does impacts the water quality. The Atlantic salmon is sensible to aluminum contamination through bioaccumulation of the residues present in the system.
Major species present:
Green sea urchin
Stimpson's surf clam
The salinity of the St. Lawrence water has a strong influence on the flora of the coastal habitats. Salt marshes are dominated by saltmeadow cordgrass, tall cordgrass, red fescue and chaffy paleacea. Present in a variable proportion, a variety of plants typical of estuarine environments: sea pea, Scotch lovage, American searocket, sea milkwort, etc. In areas submerged where substrate is thin, and water velocity is small, eelgrass grows. Eelgrass beds are home to an amazing biodiversity: shellfish, crustacean, fish, etc. which attract many predators. Several fish-eating birds such as the great blue heron come to take a meal. The Brant goose is closely linked with this habitat since the underground parts of the eelgrass are at the basis of its diet.
Potential or Ongoing Threats
Habitat loss, whether caused by human interventions (wetland drainage, road construction, urban spread, etc.) or through natural phenomena (coastal erosion) severely impact the flora. Similarly, water pollution and risks of oil spills are issues of special concern for the flora and fauna of these areas.
Major species present :
Sea pea / Beach pea