Cape Breton Island, Nouvelle-Écosse
Cape Breton Highlands National Park covers about a third of the highlands of Cape Breton Island. It stretches from the Gulf of St. Lawrence on the west side to the Atlantic Ocean on the east side. The park contains the highest elevations in the area, and consists of rounded mountains, hills and plateaus, interspersed with streams and small lakes. The park is bordered by rocky shorelines and salt marshes. Physically small, but mature Balsam Fir forests are found at the highest elevations throughout the park. These forests stay small and dense by a combination of high winds, a cool (and foggy) climate, and browsing moose. Intermixed with these forests are areas of open rock, heath barrens and bog. At lower elevations Balsam Fir, White Birch and White Spruce are dominant, and lower still are tree species such as Yellow Birch and Sugar Maple. Spruce Budworm infestations affected many highland fir forests in the 1970s.
The highland region of Cape Breton Island has a mean annual temperature of less than 50C and about 1500 mm of precipitation each year. Much of the precipitation is snow, which covers the ground from mid-November to early May. Coastal areas are warmer and receive less snow.
Many typically northern mammal species such as Lynx, Moose and Snowshoe Hare and Red-backed Vole are found here, as are other species typical of mountainous areas such as Rock Vole and Gaspé Shrew. Mink Frog and Yellow-spotted Salamander are two of the most abundant amphibians.
The Bicknells Thrush thrives in the cool misty conifer forests of the Cape Breton Highlands National Park. More Bicknells Thrushes occur here than in any other location in the province; recent surveys indicate that between 200 and 400 territorial male Bicknells Thrushes breed in the park. It is not yet clear how many thrushes this represents since recently some researchers have come to suspect that Bicknells Thrush are cooperative breeders with more than one female. These numbers represent between 2 and 8% of the global population of Bicknell's Thrush, depending on the estimate used.
The complete range of the Bicknells Thrush covers the mountainous regions of New York, Vermont, New Hampshire, and Maine and discontinuous sections of Nova Scotia, New Brunswick and Quebec. In 1995, the Bicknells Thrush became a full species, having been considered a subspecies of the Gray-cheeked Thrush ever since its late discovery in 1881. A few years later the Committee on the Status of Endangered Wildlife in Canada designated the species as vulnerable.
Other birds that breed in these high elevation forests and bogs include Greater Yellowlegs, Least Sandpiper, and possibly Solitary Sandpiper. In 1996, Hawk Owls were confirmed for the first time as breeders in Nova Scotia within the park. During the same study at least one Boreal Owl was observed regularly during the summer, and an immature Golden Eagle was also seen.
Bicknells Thrush habitat is protected at this IBA site because of its national park status. Most visitors to the park are not aware of the presence of a rare bird species, but this situation could easily change with educational programs.Catégories ZICO Habitats Usages Menaces Potencielles ou Existantes Status de Protection
|Grive de Bicknell|
|400 - 800||1995||Été|