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Salmon could
become extinct
by the middle of the
next century due to
rising seawater temperatures as
a result of global warming, the World Wide
Fund for Nature said in a report published on
Tuesday.
The report said hauls of red salmon in Alaska
sharply decreased in
1997 and 1998 when
seawater temperatures were above average.
Japanese and Canadian specialists discovered that
salmon suffer from malnutrition or starve to death in
warm water. This is
because their metabolic rate increases
and they need to take
in far more calories to survive
when the water is
warm.
The ideal water temperature for salmon is from 7 C to
15 C.
The report said that
if water temperatures
continue to rise
at the current pace,
habitats suitable for red salmon
will mostly
disappear by the
middle of the 21st century. Other kinds of salmon
vulnerable to warmer water might
also decrease.
Therefore, to
survive, salmon
either have to live
at greater depths in the sea
or migrate to cooler
northern seas that
are farther from their spawning rivers.
However, both
these alternatives have problems.
According to
recent research, salmon spend 70 percent of their lives
in waters less than 10 meters deep. It is difficult for
them to live at greater depths.
As for the second
option, if the salmon
move to northern waters, they
will have to consume
their eggs and body fat to get enough energy
to reach their
spawning rivers.