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This eco-region includes the Canadian Arctic territories
of Nunavut, Yukon and the Northwest
Territory; Russiašs Northern Coast; Greenland;
the Norwegian provinces (fylke) of Finmark
and Troms; Norway's dependencies of Svalbard
and Jan Mayen Islands.
Whilst the freezing waters of the polar Arctic are
not a natural destination for recreational divers,
there are a number of important Large Marine Ecosystems
(LMEšs) that are worthy of note.
The Kara Sea Large is located within the Arctic
Circle on the huge Siberian shelf. This shallow sea
is seasonally ice covered. The influx of warm ocean
currents from the North Atlantic and high salt levels
help provide mainly ice-free conditions from May to
October, whilst a number of rivers (The Yenisei, Taz
and Ob) discharge into the sea and are an important
source of fresh water and nutrients. The rocky coasts
harbour many small bays and inlets and are covered
in shrubs and moss. There are many diverse habitats
in this region. The Kara Sea LME is considered to
be low in productivity, primarily because of the winter
ice cover and the limited availability of both light
and nutrients. Zooplankton biomass production is relatively
low, and the distribution and species composition
is influenced by the proximity of the Atlantic Ocean
A diversity of wildlife is found in the area, including
bearded seals, walruses, and narwhals. The polar bear
hunts for seals on the frozen edge of the sea and
fish such as Arctic cod, flatfish, and smelt are abundant.
The largest marine protected area on the northern
hemisphere, the Franz-Josef-Land nature reserve, is
located within the region.
The Barents Sea is another shallow sea, bounded
by Atlantic water in the south and west, and by Arctic
or mixed water in the north and east, with large seasonal
and annual changes in ocean climate. The distribution,
growth and recruitment of the areašs major fish species
is greatly influenced by climatic conditions, with
ice covering between one and two thirds of the sea.
The ice cover varies considerably by season and by
year. Deemed to be moderately productive, the Sea
is affected by three major current systems, the Norwegian,
the Atlantic and the Arctic current systems. The ecosystem
is characterized by a food web with only a few dominant
species such as diatom, krill, capelin and cod. The
Bering Strait and associated islands is a critical
area for marine life migrating to and from summering
grounds in the Chukchi Sea and elsewhere in the Arctic
Ocean. The region supports huge seabird populations,
including nearly 2 million murres and auklets, as
well as one of the largest salmon runs in the world.
There are also extensive kelp forests and eelgrass
beds in coastal lagoons.
The terrestrial portion of this area includes polar
desert (the word "Svalbard" in fact means "cold desert"),
as well as productive tundra areas. Arctic terns breed
here, before traveling 36,000 km to winter in Antarctica.
The strait is used by 14 species of marine mammals,
such as the endangered bowhead (Balaena mysticetus)
and gray whales (Eschrichtius robustus), several species
of seals, and walruses (Odobenus rosmarus).
The West Bering Sea is considered moderately
productive, and includes over 450 species of fish,
crustaceans and mollusks. The reported 25 species
of marine mammals include polar bears, whales, walruses,
and sea lions. The Bering Sea provides important habitat
for gray whales, endangered stellar sea lions and
a large diversity of seabirds. The sea hosts the worldšs
largest fish biomass for Pacific cod and cod-like
fishes, with other fisheries including salmon, Alaskan
pollock, walleye pollock, flatfish, rockfish, halibut,
flounder and herring. The extent of the winter pack
ice has markedly decreased, with the winter of 2001
heralding a relatively ice-free Bering Sea. Is diving
amongst icebergs, seals, seabirds, walruses and polar
bears in sub zero waters the ultimate dive challenge?
There are a small number of organisations geared to
help you to do just that. Important with all diving
activities, even more important here, you must always
be certain that you are in skilled, professional hands
when you venture into the unknown.
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