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nineteenth century, the Yukon's role as a trans-
portation link between the coast and the interior
of Alaska was established with the fur trade and
gold rushes. Today, the larger Yukon basin's
ecological importance is perhaps best illustrated
by the large number of established conservation
areas. The basin contains wholly or partly seven
national wildlife refuges (NWR), including the
Yukon Delta NWR (U.S. Fish and Wildlife Service
2011b). It also contains sections of four national
parks, including parts of Denali and Wrangell-
St. Elias, and areas managed and protected by
the Bureau of Land Management (National Park
Service 2011). The Yukon Delta NWR is one of
the largest of its kind in the United States and
includes the deltas of both the Yukon and
Kuskokwim rivers. It is particularly well known
for supporting millions of migratory waterfowl,
shorebirds, cranes, loons, grebes and other
species. The delta also provides essential i sh
habitat and is vital for commercial Pacii c salmon
i sheries as well as local salmon and other i sh
economies.
Salmon has been a long-standing part of the
culture and economy of resident native commu-
nities like the Yup'ik. It is considered an anadro-
mous i sh species, which spends part of its life
cycle, including hatching, in fresh water, matur-
ing in ocean, returning eventually to fresh-water
systems to spawn and ultimately die. Chinook
( Oncorhynchus tshawytscha ), Chum ( O. keta )
and Coho ( O. kisutch ) salmon use upstream and
downstream areas of the Yukon basin to spawn,
feed, and also partially mature before entering
the ocean. During the spawning season, salmon
travel hundreds of kilometers inland from the
ocean to reach spawning beds in the upper
Yukon. Alongside food obtained by hunting and
other subsistence activities, salmon is consid-
ered a staple and is preserved, dried or smoked
to provide a year-long source of food and eco-
nomic security for resident populations.
Salmon is also a commercially signii cant
species and growing demand has led to
increased harvesting pressures on the i shery.
The i sh is an important link in the Arctic trophic
food chain and studies suggest that changing
salmon populations could have far-reaching
consequences on other dependent i sh and
mammal populations (Loring and Gerlach 2010).
The Alaska Department of Fish and Game,
through management strategies, attempts to
strike a i ne balance between supporting the
subsistence needs of upstream and downstream
local populations, the demands of commercial
i sheries, and maintaining healthy biologically
viable salmon stocks (Loring and Gerlach 2010).
Yet meeting such competing needs is a difi cult
task. Compounding these challenges, climate
change impacts including the thawing of per-
mafrost, drying of wetlands, warmer water tem-
peratures, earlier ice-out conditions, increased
storm activity and runoff may all inl uence
salmon runs as well (Anisimov et al. 2007;
Loring and Gerlach 2010).
17.4.3 Lena River delta, Russia
Moving to the Arctic coast of Eurasia, the delta
of the Lena River is among the most spectacular
wetland complexes in the world. The Lena River
is noteworthy for both its length and the volume
of fresh water it brings to the Laptev Sea in the
Arctic Ocean. The Lena traverses nearly 4,300 km
in length from its source in the Baikal highlands
region of central Russia to its mouth. Fresh-
water inputs inl uence the temperature and
local circulation of the Laptev Sea, and the sig-
nii cant sediment nutrient load supports a
vibrant terrestrial and marine ecosystem (Costard
and Gautier 2007). From its source, the river
l ows northeastward till it reaches the city of
Yakutsk, which is the largest in the region and
the capital of Russia's Sakha Republic (also
known as Yakutia). The Lena then turns and
l ows northward to its mouth in the Laptev Sea.
The greater Lena basin, along with its four
primary tributaries, extends over several differ-
ent biomes including steppe grasslands, a wide
belt of taiga forests, and permafrost tundra land-
scapes in its far northern reaches.
The river breaks into numerous branches and
channels in a wide fan-shaped delta extending
over roughly 28,000 km 2 before entering the
Laptev Sea (Costard and Gautier 2007). The Lena
Delta stretches between approximately 72° N to
74° N latitude and 122° E to 129.5° E longitude.
It comprises an entirely tundra landscape, frozen
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