Marais de la baie de L'Isle-Verte

Site description (2001 baseline):

Site location and context
Baie de l'Isle-Verte is a cove located beside the town of Saint-Jean-Baptiste de l'Isle-Verte, on the St. Lawrence River estuary, Québec. This town is located approximately 30 km east of Rivière-du-Loup. A National Wildlife Area (NWA) encompassing the marsh (marais) extends along km of shoreline to the west and east of the town, and a smaller Migratory Bird Sanctuary is centred in the middle of the NWA. There is a succession of different habitat types, from the estuarine waters and tidal marshes composed of saltwater cord-grass, to prairies of salt-meadow grass, and finally to coastal alder swamp. Its main feature is a vast marsh dotted with ice extraction pans created by the action of the retreating ice in the spring. This is the site of the largest remaining spartina marsh in southern Quebec. At low tide, the marsh has a minimal and maximal width of 610 m and 1070 m respectively. A constant supply of fresh water to this site is provided by a river and a few brooks.

Key biodiversity
Baie de l'Isle-Verte is a significant site for Greater Snow and Canada Geese. During spring and fall migrations, as many as 27,000 geese have been observed at this site. At the same time, greater than 4,000 Black Ducks (about 4% of the estimated Atlantic flyway population) can be observed at these sites. Other wayterbird migrants include: Green-winged Teals, Northern Pintails, Common Eiders, scoters, gulls and cormorants.

The variety of habitats found within Baie de L'Isle-Verte attract a large number of bird species throughout the year. Within the National Wildlife Area, more than 260 bird species have been recorded, including some rare species, such as Eurasian Widgeon, King Rail, Laughing Gull, Hawk Owl, Marsh Wren and Wilson's Phalarope. The Nelson's Sharp-tailed Sparrow, a species found only locally in Québec, breeds in Baie de L'Isle-Vert. Among the shorebirds that have been recorded are Whimbrel, Greater Yellowlegs, Black-bellied Plover, Semipalmated Plover, Spotted Sandpiper, Hudsonian Godwit, Common Snipe, Pectoral Sandpiper, Least Sandpiper, and Semipalmated Sandpiper. Older breeding season surveys recorded 501 Black Duck ducklings (1968), 386 ducklings (1969), and 167 broods in 1970.

Conservation responses/actions for key biodiversity
Baie de l'Isle Verte National Wildlife Area was created in 1980 mainly to protect the Spartina spp. marshes, an important habitat for the American Black Duck: 13 % of this 548 ha National Wildlife Area (NWA) is occupied by tidal marshes. In 1986, the Isle-Verte Migratory Bird Sanctuary (MBS) was added to protect staging habitat for geese and ducks. The NWR is overlapped partially by this MBS around the Anse Verte area. The rest of the tidal marsh and flats of Baie de l'Isle-Verte, approximately 2840 ha, is under provincal jurisdiction. The federal and provincial properties are protected by the Ramsar Convention status given in 1987. Although much protection is afforded to this site, it still remains vulnerable to oil spills.

Recommended citation
BirdLife International (2023) Important Bird Area factsheet: Marais de la baie de L'Isle-Verte. Downloaded from on 26/09/2023.