This large ecoregion occupies a significant part of northern Quebec and most of Labrador, stretching from Hudson and James Bay to the west, southern Ungava Bay to the north, and the Atlantic Ocean to the east.
The mean annual temperature in this [ecoregion] ranges from -6°C to 1°C, with lower temperatures occurring closer to Hudson Bay and warmer temperatures in eastern Labrador. Mean summer temperatures range from 5.5°C to 10°Celsius (C), and mean winter temperatures range from -18°C to -1°C. Mean annual precipitation varies greatly between 300-400 millimeters (mm) in the area directly south of Ungava Bay to 1000 mm in the southeastern part of this ecoregion. This large ecoregion is characterized by a range of low, mid and high subarctic ecoclimates, and experiences cool summers and very cold winters, with the exception of the coastal barrens, influenced by the Atlantic Ocean and characterized by short, cool moist summers, and longer winters.
The physiography of this ecoregion is rough and undulating, and is composed mainly of massive Archean granites, granitic gneiss, and acidic intrusives with some sedimentary rock found along the coast. Glaciation has given this ecoregion a rolling, morainal plain with numerous small, shallow lakes. Permafrost is found throughout the ecoregion in isolated patches, especially in wetlands.
The western portion of this ecoregion is composed of the Larch Plateau and the Richmond Hills and has a hummocky surface with elevations ranging from 150 meters (m) above sea level (asl) near the coast of James Bay to 450 m asl further east, precipitation to flow eastward to Ungava Bay and westward to Hudson Bay. Kaniapiskau Plateau forms the core of Lake Plateau in the central and south-central area, and is composed of massive granulite and charnockite Archean rocks. Portions of the plateau reach elevations of 915 m asl. An escarpment runs from northwest to southeast through the center of the ecoregion overlooking the Labrador Hills, which are composed of folded Precambrian sedimentary and volcanic rocks. Their surfaces are in the form of sinuous ridges and valleys formed by down-warped, folded, and faulted strata. Summit elevations here range from 360 m asl to 730 m asl. Along the Atlantic coast, steep-sided, rounded mountains with deeply incised U-shaped valleys and fjords extending inland along the Labrador Sea coast. Discontinuous, sandy, bouldery morainal veneers dominate its surfaces. The southeastern edge of the ecoregion is level to gently undulating peatland, interrupted only by a few conspicuous eskers, exposed bedrock highs, and shallow rivers.
Vegetation consists of open, stunted stands of black spruce (Picea mariana) (climax species) and tamarack, with secondary quantities of white spruce (P. glauca) and dwarf birch (Betula spp.), willow (Salix spp.), ericaceous shrubs (Ericaceae), cottongrass (Eriophorum spp.), lichens and moss. Poorly-drained sites support sedge (Carex spp.), Labrador tea (Ledum groenlandicum) cottongrass, and sphagnum moss (Sphagnum spp.). The northwestern boundary of this ecoregion is where the tree limit is reached in Quebec, and trembling aspen reaches its northern limit in the Mecatina River ecoregion in Labrador. Balsam fir (Abies balsamea) is restricted to rare sites of medium-textured materials. The Kingarutuk-Fraser River area and Mealy Mountains form extensive tundra barrens with continuous vegetation cover restricted to depressions where snow accumulates and provides moisture throughout the growing season. Throughout the south, open coniferous forest is transitional to the closed coniferous boreal forest to the south, and the tundra and alpine tundra communities in the northern part of this ecoregion. In the south, open stands of lichen, and black and white spruce with feathermoss understory dominate. Toward Ungava Bay in the north, vegetative cover becomes more sparse and more open. Along the Atlantic Coast, low, closed to open white spruce forest with a moss understory is found on most slopes; however, coastal heath dominates along headlands and ridges, and cliff summits are mainly exposed bedrock with mosses and lichens limited to cracks. Salt marshes and plateau bogs are common on large marine terraces near the coast as well. In the eastern tip, extensive string bogs with open water dominate, and are surrounded by sedges, brown mosses, and sphagnum mosses.
Caribou (Rangifer spp.), moose (Alces alces), black bear (Ursus americanus), wolf (Canis lupus), red fox (Vulpes vulpes), arctic fox (Alopex lagopus), wolverine (Gulo gulo), snowshoe hare (Lepus americanus), grouse (Dendragapus spp.), osprey (Pandion haliaetus), raven (Corvus corax), and waterfowl are species common in this ecoregion. The Atlantic [coastal zone|Coast]] of this ecoregion forms part of the Atlantic migratory flyway and provides important habitat for seabird colonies, as well as seal (Phocidae) whelping areas. This ecoregion also provide important habitat for peregrine falcon (Falco peregrinus) and the eastern harlequin duck (Histrionicus histrionicus), both endangered species in Canada.
Outstanding features of this ecoregion include most of the year-round range of the George River barren ground caribou herd (Rangifer tarandus ssp. arcticus), the world’s largest migrating herd with an estimated 800,000 animals. String bogs are widespread in this ecoregion and may be considered among the most extensively developed examples in North America. In addition, a small (estimated to be less than 300 animals) and very rare population of land-locked freshwater seals inhabits Lac des Loups Marins, Quebec.
Habitat Loss and Degradation
Remaining Blocks of Intact Habitat
The majority of the ecoregion remains intact.
Degree of Fragmentation
Little habitat fragmentation; some fragmentation may result locally from flooding by hydro-electric dams.
Degree of Protection
There are no protected areas in this ecoregion that meet IUCN I-III protection standards.
Types and Severity of Threats
Future hydro-electric projects are proposed for many of the ecoregion’s major rivers, particularly in Quebec. Locally, mining activity is significantly increasing in some areas (e.g. Voisey’s Bay, Labrador) and a real threat of logging exists in the southeastern portion of the ecoregion in Labrador. Caribou harvest must be closely managed so as not to threaten the George River herd in the future, particularly if a population crash occurs as has happened in the past.
Suite of Priority Activities to Enhance Biodiversity Conservation
Protected areas need to be permanently established. The following are some important candidate sites:
- Mealy Mountains National Park - southeast Labrador
- Lac Joseph - Atikonak proposed provincial wilderness reserve - southwest Labrador
- Lac Guillaume-Delisle - west-central Quebec
- Lac a l’eau claire - west-central Quebec
- Baie aux feuilles - northeast Quebec
- Lac Burton-Riviere Roggan et la pointe Louis XIV - west-central Quebec
- Riviere Koroc - northeast Quebec
- Monts Pyramides - northeast Quebec
- Lac Cambrien - northeast Quebec
- Canyon Eaton - northeast Quebec
- Collines Ondulees - northeast Quebec
- Confluence des rivieres de la Baleine et Wheeler - northeast Quebec
- Lac Bienville - central Quebec
- Action: Environment
- Grand Conseil des Cris
- Newfoundland/Labrador Environmental Association
- Protected Areas Association of Newfoundland and Labrador
- The Nature Conservancy, Quebec
- UQCN - Union Québecoise pour la Conservation de la Nature
- World Wildlife Fund Canada, Quebec Region
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