Strait of Belle Isle Barrens 9
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ECOREGION Forest Barren Tundra Strait of Belle Isle Bog NF 9 Barrens 1 he Strait of Belle large areas of exposed bedrock. On the west TI s l e B a r r e n s side of the peninsula, the terrain is marked by flat, 2 ecoregion covers rocky, coastal barrens underlain primarily by 1,889.1 km5 and limestone. An interesting feature of this area is occupies the low, the presence of "stone polygons": a series of 3 treeless, northern tip and west coast of the Great ring-like structures made of coarse materials and Northern Peninsula on the island of formed by freeze-thaw cycles. To the east, these Newfoundland. This part of insular barrens give way to rocky hills underlain by 4 Newfoundland was underwater during the sandstone and slate. Pleistocene age. Today, almost no part of it rises This difference in the underlying rock higher than 60 metres above sea level. types on an east-west gradient leads to 5 Compared to the Island's other distinctive changes in the associated vegetation. e c o r e g i o n s , i t s m o s t s t r i k i n g In particular, the calcium-rich barrens along the 6 characteristic is its cold temperatures. west coast are host to a varied and unique group In winter, ice floes carried by the of plants, many of which are rare. Labrador current pack into the Strait Due to its location at the 7 of Belle Isle, eliminating any northern tip of the Island, the Strait of moderating effects the water Belle Isle ecoregion is also notable would have on temperatures. Strait of Belle Isle for its visits by wildlife from 8 Because this pack ice does not Ecoregion Labrador. The occasional polar fully break up until June or early bear can appear in spring, for 9 July, spring comes late to the example, arriving on the south- Strait of Belle Isle Barrens ecoregion. flowing ice in search of prey, Not only does the area experience the primarily seals. Other interesting LAB shortest growing season of any other ecoregion visitors are northern bird species, including the on the Island, but frost can occur during any pigeon-sized ivory gull, whose dark legs and bill 1 month of the year. Fog frequency is also high, set against an all-white plumage make it a particularly in summer. special treat for bird-watchers. Ivory gulls are 2 Throughout the Strait of Belle Isle scavengers and depend on dead seals and other Barrens, soil depths are shallow and there are marine mammals for much of their diet. 3 Soils: Soils in this ecoregion are generally "organic mesisols" — soils composed mostly of organic matter and usually found in peatlands. In the northeast we find an area of partially exposed bedrock with a thin soil layer (less than 10 cm.) 4 Ecoregion: An area that has distinctive plant life found on them belongs to the Fens: Like bogs, fens are a type of 5 and repeating patterns of vegetation and heath family. peatland, though they generally have soil development, which are determined more grasses and sedges than bogs, and and controlled by regional climate. Arctic-alpine plants: A descriptive term so look more meadow-like. Peatlands are Ecoregions can be distinguished from for plants that cannot grow where there are wetlands characterized by poor drainage 6 each other by their plant communities, hot summer temperatures. Arctic-alpine and a thick layer of peat (soil consisting of landscapes, geology, and other features. plants are generally found farther north the remains of partly decomposed plants). These characteristics, in turn, influence than the treeline (by latitude), or above the Shrubs and mosses are the common the kinds of wildlife that can find suitable treeline elevation on mountains. plants in peatlands, particularly sphagnum 7 habitat within each ecoregion. moss. While bogs receive most of their Tuckamore: Also known as "krummholz," nutrients from rainfall, water entering fens Barrens: Primarily treeless areas tuckamore are areas where growth- seeps in from nearby soils, resulting in a 8 containing low-growing plants that are well limiting factors (such as exposure to harsh more nutrient-rich habitat. adapted to exposed conditions and soils weather, or excess soil moisture) have low in nutrients. Barrens are also known as resulted in dense thickets of stunted "heath" or "heathlands," since much of the coniferous trees. 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 — Strait of Belle Isle Ecoregion scrub spruce limestone heath empetrum heath snowbeds tuckamore fen 60 m ocean Sea Level Geology: The rocks in the Strait of Belle Isle Barrens ecoregion fall into two major categories. In the west are limestones and dolostones formed about 550 million years ago in a shallow sea. These rocks are high in calcium carbonate, which originated from organisms living in this sea. Numerous seacaves — common along limestone coasts — also occur here. In the northeast are shales and sandstones deposited about 450 million years ago. Some of these deposits were later twisted and squeezed under great pressure to form a metamorphic rock called slate. Sandstones are sedimentary rocks that were deposited during the erosion of the ancient continent of Laurentia. Limestone underlies the flat are considered rare or uncommon, barrens of the west coast, and it including mountain avens, lapland Vegetation Profile yields calcium-rich, basic soils with rosebay, white orchid, and flame a high pH. The soil here is not very lousewort. s a result of the cold conditions, thick, however, and extensive To the east, slate and Avegetation in the Strait of Belle areas of exposed rock and gravel sandstone underlie the more hilly Isle ecoregion is tundra-like and are common. Because the soil in terrain, resulting in acidic soils and includes many arctic-alpine plants this narrow coastal belt differs a community of plants similar to the such as dwarf willow and velvet- d r a m a t i c a l l y f r o m e a s t e r n exposed coast of southern bells. Low, dense masses of Newfoundland, so too does the Labrador. Alpine bearberry, alpine tuckamore containing white birch, plant community that grows here. azalea, and pink crowberry are black spruce, and balsam fir occur Many of the plants found on this examples of plants that commonly throughout the area. Although the western stretch of the coastline occur in these barrens. region is primarily characterized by grow only in calcium-rich soils, and barrens and scattered tuckamore, small areas of forest do occur, particularly in the Pistolet Bay area. In comparison to the extensive peatlands found just to the south in the Northern Peninsula Forest ecoregion, peatlands in the Strait of Belle Isle Barrens are small and generally consist of nutrient- n a rich fens alternating with dry barren y R areas. n e l M a j o r c h a n g e s i n G A vegetation occur in the ecoregion : o t on an east-to-west gradient. These o h changes are largely due to P differences in the underlying bedrock, which affects the pH level Species in Focus: Dwarf hawksbeard (Crepis nana) is a rare arctic (or acidity) of the soil. This, in turn, plant. Its only known location on the Island is in the limestone gravels affects the ability of plants to take up on Burnt Cape in the Strait of Belle Isle ecoregion. It is a small plant nutrients. Some plants are adapted with a rosette of narrow, deep green leaves. In early July it produces a to basic soils, which are low in few tiny yellow "daisys" that are essentially stemless and sit in the acidity and have a high pH. Others middle of the leaves. are better adapted to acidic soils, which have a low pH. 2 Strait of Belle Isle Barrens ecoregion Wildlife Profile notable wildlife phenomenon in Athe Strait of Belle Isle Barrens is the regular visits by birds more typically found only in arctic areas, such as the gyrfalcon, Lapland longspur, hoary redpoll and the endangered ivory gull. The area also plays host to considerable numbers of migrating shorebirds h s during late summer, including the i v a white-rumped sandpiper and ruddy t c turnstone. a M e Tree sparrow, Savannah c u sparrow, and white-crowned r B : sparrow occur here as migratory o t o breeders — that is, they breed here h P but migrate elsewhere for the winter. Common eiders nest on the Species in Focus: The American pipit nests on the open coastal islands of Sacred Bay and barrens in the Strait of Belle Isle Barrens ecoregion. It is a on islands in freshwater ponds near brownish bird with dark streaks on the breast and white outer Pistolet Bay Provincial Park. tail feathers that are visable when in flight. Instead of hopping, it This ecoregion is also one of walks along the ground, bobbing its tail almost constantly. the best areas on the Island to see the ground-nesting short-eared owl. These owls hunt most actively during the evening but can be seen There are no at other times of the day or night. amphibians or reptiles P o l a r b e a r s a r e a n found in the Strait of occasional visitor during the spring Belle Isle Barrens.