High Subarctic Tundra

ECOREGION Forest Barren Tundra Bog L3 High Subarctic Tundra NF 1 h e w i d e l y Mealy Mountains, just south of Lake Melville, T scattered High contain some of the highest mountains in Subarctic Tundra is Labrador, some of which remain snow-covered 2 primarily an inland year-round. ecoregion. It is marked by high plateaus and This rugged, mountainous ecoregion is 3 mountains dissected by the upper reaches of dominated by large areas of exposed bedrock, fjords, with elevations ranging from 600 to 1,000 with some steep-walled valleys, such as at Harp metres above sea level. Lake and the Fraser River valley. Scattered rock 4 The ecoregion's boundary extends debris and talus are common. from the northern tree limit at Napoktok Bay Vegetation is limited, and greatest in south to include the George River valleys. However, compared to the Alpine 5 Plateau, then west along the border Tundra ecoregion to the north, where trees between Quebec and Labrador, are limited to small stands of deciduous 6 encompassing pockets of land trees and conifer trees are absent, this c h a r a c t e r i z e d b y h i g h ecoregion is characterized by the elevations. High Subarctic presence of conifers and by slightly 7 There are also several Tundra more extensive forest cover. outliers located farther south, Ecoregion Due to the cold climate of including areas on the this ecoregion, lakes can remain 8 McPhayden Plateau, Benedict frozen as late as July. In the M o u n t a i n s , R e d W i n e McPhayden Plateau area, 9 M o u n t a i n s , a n d M e a l y lakes are often linear in Mountains. shape, following fault The McPhayden Plateau lines in the bedrock. LAB is a rocky upland area located along the western edge of 1 Labrador. The rounded Benedict M o u n t a i n s o c c u r n o r t h o f 2 Groswater Bay where they rise abruptly Soil Profile: Rocklands dominate the land with pockets of orthic humo-ferric podzols and from the Labrador Sea, while the Red Wine orthic dystric brunisols common throughout Mountains are located in central Labrador. The the ecoregion. 3 Ecoregion: An area that has Fjord: A deep U-shaped valley Fens: Wetlands characterized 4 distinctive and repeating formed by a glacier and by poor drainage and a thick patterns of vegetation and soil afterwards filled by sea water layer of peat — soil consisting 5 development, which are to form a long, narrow, steep- of partially decomposed determined and controlled by sided inlet. plants. The dominant plants in regional climate. Ecoregions fens are often sedges, 6 can be distinguished from Talus: The collection of rock grasses, shrubs, and mosses, each other by their plant and rubble that forms at the particularly sphagnum moss. communities, landscapes, base of a slope as material 7 geology, and other features. erodes off the mountainside Outwash terrace: A level These characteristics, in turn, above. Commonly known as sand or gravel surface partway 8 influence the kinds of wildlife "scree.” up a slope that was laid down that can find suitable habitat by a glacier- fed stream. within each ecoregion. 9 Check your public library for a full set (36) of these booklets: one introductory document and one for each of the 35 ecoregions and subregions in the province. For more information about the series see page 4. 10 Landscape Profile - High Subarctic Tundra 1000 m rock gardens willow lichen shrub birch spruce pond 600 m Geology: This ecoregion spans all four of the geologic provinces of Labrador. The majority of the ecoregion, however, falls within the Churchill Province, and is underlain by gneisses and other metamorphic rocks between 2.5 and 1.7 billion years old. Large bodies of granitic, gabbroic, and anorthositic rocks, dated at about 1.3 billion years, have intruded these metamorphic rocks; the intrusions host the Voisey's Bay nickel deposit. Gneisses of the Superior Province underlie the large outlier in the McPhayden River area in western Labrador. Other, smaller outliers occur to the south, generally over high ground underlain by some of the more resistant rocks of the Grenville Province. grow, a characteristic that association with black spruce in Vegetation distinguishes the High Subarctic these forests. On the outwash Profile Tundra from the Alpine Tundra terraces of valley floors, spruce ecoregion. White birch and willow forests are more open — that is, pland areas in the High thickets (which can survive on the trees are more widely spaced. The USubarctic Tundra ecoregion less-stable scree) often form a lichen understory that occurs here are much like those in the Alpine transition zone between the tundra can be extensive and thick. The Tundra ecoregion to the north — above and the black spruce forests main lichens are Stereocaulon the landscape is primarily tundra, on the slopes below. species rather than the caribou with vegetation limited to patches Larch, balsam fir, and white lichens that dominate farther of lichens, willows, sedges, birch occasionally grow in south. mosses, and dwarf shrubs. For the most part, tundra occurs around the Arctic Circle above the treeline and is characterized by a very short growing season. Bare rock accounts for more than 50 percent of the surface area of the plateaus in this ecoregion. A continuous cover of n vegetation in high areas occurs a y R only where snow accumulates, n e l such as in depressions, which n a G y . yield enough moisture to sustain R A n : plants throughout the growing e l o t G season. These areas of plant o A h : P growth are known as snow-bed o t o communities. h Species in Focus: Larch (Larix laricina), which is also known as tamarack or P Shallow fens, containing juniper, is the only coniferous tree in Canada that is also deciduous. This various sedges, sphagnum means that, unlike other conifers such as spruce and fir, larch loses its needles mosses, and some bog laurel, also each fall and produces new ones each spring. Found throughout occur on plateaus where drainage Newfoundland and Labrador in bogs, barrens, and forests, larch is often the is poor. first tree species to colonize disturbed sites such as roadside embankments. At lower elevations in the In summer its needles are a feathery bluish-green. In fall, larch turns a vibrant ecoregion, however, forests do yellow and stands out brightly against the surrounding spruce and fir. 2 High Subarctic Tundra ecoregion Wildlife Profile his is the most important region in Labrador for caribou. In the T n o tundra portions of this ecoregion, i s i v caribou, arctic fox, Ungava i D lemming, red fox, northern bog s a e lemming, and arctic hare can be r A l found. Mammals found in the a r u forest and shrub areas of the valley t a N slopes include lynx, woodchuck, d n snowshoe hare, mink, heather a s vole, masked shrew, porcupine, k r a and red squirrel. P : o Meadow voles live in t o h wetland areas; mammals that live P in a variety of habitats within the Species in Focus: Members of a number of caribou herds appear ecoregion are black bear, short- seasonally on the tundra. Part of the calving area for the George River tailed weasel, wolf, and least caribou herd is in the northern portion of the High Subarctic Tundra weasel. Beaver, muskrat, and river ecoregion. The George River herd had an estimated 385,000 animals in otter are the main aquatic 2001, a major reduction from the 1993 estimate of 700,000 animals. mammals. However smaller numbers has resulted in generally healthier animals and The vast majority of bird has allowed the population of neighbouring barren-land herds to increase. species in the High Subarctic Other woodland herds, such as the MacPhayden, Benedict Mountain, Red Tundra are present as breeders Wine, and Mealy Mountain populations, are present in the ecoregion's during the spring and summer, outliers to the south and west. The North American caribou is the same species as the reindeer of then migrate south for the winter. northern Europe and Asia. Compared to the island of Newfoundland, Exceptions are willow and rock Labrador provides vast areas of good habitat for caribou. Caribou's natural ptarmigan and raven, all of which predators include lynx, bear, and wolf, which it detects almost entirely are year-round residents here. through its sense of smell. Young caribou are particularly vulnerable, Characteristic breeding although a two to three-day-old calf can outrun a lynx or bear. birds of the barrens include rough- legged hawk, peregrine falcon, ecoregion are arctic char, snow bunting, and Lapland three-spine stickleback, longspur. Typical birds inhabiting nine-spine stickleback, forested areas are merlin, northern brook trout, lake trout, flicker, blackpoll warbler, pine northern pike, white grosbeak, American robin, and sucker, and slimy sculpin. three-toed woodpecker. Tree Atlantic salmon and sparrow, white-crowned sparrow, rainbow smelt occur and northern shrike are found in o c c a s i o n a l l y . N o shrub/thicket habitats. Lincoln's amphibians or reptiles sparrow occurs in wetlands. occur in this ecoregion. Waterfowl found breeding in the vicinity of freshwater include Canada goose, red-breasted Ugjoktok Fjord, with its merganser, and the harlequin steep-sided valley walls duck, whose eastern population is reaching over 500 metres designated as special concern.

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