Canadian Biodiversity: Ecozones: Hudson Plains

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Location | Climate | Geology and geography |
Flora and fauna | Humans
Location
The Hudson Plains stretch from Manitoba to
Quebec along the southern edge of Hudson Bay.
Climate
Canada contains a quarter of the world's
wetlands, and the Hudson Plains ecozone's poor
drainage has resulted in the largest continuous
wetlands in the world. Hudson's Bay moderates
the temperature in summer, but the ice that
covers it in winter prevents most of this; average
summer temperatures are 11ºC, but in winter the
average temperature is -18ºC. Precipitation
ranges from 400mm in the northwest to 800mm
in the southeast.
Geology and Geography
The terrain here is flat, and the poor drainage
encourages the creation of wetlands and bogs.
Palaeozoic and Proterozoic sedimentary bedrock
slopes gradually towards Hudson Bay.
Flora and Fauna
Plants
Vegetation here follows two basic patterns. The
first ranges from north to south; in the north, the
terrain is treeless tundra, but in the more
southern taiga trees appear, getting thicker as
one keeps moving south. The second pattern
follows altitude. Because the drainage here is
poor, trees are only found at the drier higher
altitudes, while the lower altitudes lack trees.
This results in belts of trees following the ridges
in striking patterns. Some characteristic tree
species are black spruce, white spruce,
tamarack, balsam poplar, dwarf birch, paper
birch, shining willow, Bebb willow, and trembling
aspen. Other plants include eriacaceous shrubs,
cottongrass, sphagnum moss, northern Labrador
tea, lapland rosebay, black crowberry, blueberry,
cloudberry, arctic aven, purple saxifrage, prickly
saxifrage, lousewort, reindeer moss, and caribou
lichen.
Animals
Diversity is highest in summer, when migrating
birds appear in huge numbers to breed. The
region is more famous for its biting insect
population, which takes advantage of the poor
drainage to breed in huge numbers. A single
hectare is estimated to be able to produce ten
million black flies, no-see-ums and other biting
insects!
Mammals
Characteristic large herbivores include caribou,
mule deer, white-tailed deer, moose, mountain
goat, and California bighorn sheep. Large
carnivores that are found here include black
bear, grizzly bear, polar bear, wolf, and lynx. The
small herbivores include hoary marmot,
Columbian ground squirrel, brown lemming,
snowshoe hare, beaver. The small carnivores of
the Hudson Plains include coyote, red fox, arctic
fox, fisher, marten, mink, wolverine, hoary bat,
red bat, and river otter. Some aquatic mammals
that can be found are bearded seals, harbour
seals, ringed seals, beluga, and bowhead
whales.
Birds
Some of the characteristic birds of prey are
northern goshawk, boreal owl, short-eared owl,
red-tailed hawk, common nighthawk, and merlin.
Shorebirds and seabirds that are found here
include semipalmated sandpiper, spotted
sandpiper, pectoral sandpiper, american bittern,
common snipe, killdeer, and yellow rail. The
songbirds of the region include Stellar’ s jay,
black-billed magpie, Smith's longspur, common
redpoll, common crow, rusty blackbird, and tree
swallow. Waterfowl such as Canada goose,
snow goose, American black duck, northern
pintail, tundra swan, green-winged teal, mallard,
American black duck, and ring-necked duck are
found here. Birds of the forest include blue
grouse, ruffed grouse, willow ptarmigan, northern
flicker, and downy woodpecker.
Amphibians and Reptiles
Three frog species that live in the Hudson Plains
are the striped chorus frog, northern leopard
frog, and wood frog.
Fish
Predators such as lake sturgeon, brook trout,
northern pike, and walleye prey on such species
as lake herring, lake whitefish, lake chub, pearl
dace, and ninespine stickleback.
Molluscs
Both the muskeg stagnicola and arctic-alpine
fingernail clam can be found here.
Insects
The Hudson Plains are notorious for their
populations of biting insects.
Humans
A lack of timber and minerals means that tourism
and subsistence activities are the means by
which the 10 000 people who live here make
their living.
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