Global Warming: Polar bears are hungry
London, Jan 2: We humans are causing polar bears to go hungry. If the questions persists 'How'? Read on. Of course it is Global warming. The melting of sea ice are causing polar bears to go hungry, with the number of undernourished bears tripling in a 20-year period, according to new estimates.
According to a report in New Scientist, the estimates were done by Seth Cherry of the University of Alberta, Canada, and colleagues, who monitored the health of polar bears in the ice-covered Beaufort Sea region of the Arctic during April and May in 1985, 1986, 2005 and 2006. They immobilized the bears using tranquillizer darts and measured the ratio of urea to creatinine in their blood.
A low ratio means that nitrogenous waste material is being recycled within the body and indicates the animal is fasting - a state which usually only occurs temporarily in males during the spring breeding season.
In
1985
and
1986,
the
proportion
of
bears
fasting
was
9.6
and
10.5
per
cent
respectively.
By
2005
and
2006,
this
had
risen
to
21.4
and
29.3
per
cent.
Cherry's
team
believes
that
the
increase
in
fasting
bears
is
explained
by
warmer
temperatures
and
earlier
spring
melts.
Polar
bears
use
sea
ice
as
a
hunting
platform,
catching
seals
by
sitting
next
to
their
breathing
holes
and
waiting
to
pounce.
Spring
is
usually
a
time
of
feasting
for
polar
bears,
filling
up
before
summer
when
the
ice
retreats.
"It
is
clear
that
the
changes
in
the
sea
ice
are
affecting
the
hunting
opportunities
available
to
the
bears," said
co-author
Andrew
Derocher
of
the
University
of
Alberta.
The
early
melting
may
also
be
resulting
in
a
lack
of
prey,
according
to
researchers.
Sea
ice
is
important
to
seals
because
they
build
dens
for
their
pups
in
the
overlying
snow,
so
their
numbers
may
have
dropped,
explained
Cherry.
Anecdotal evidence backs up the team's conclusions, with many more sightings of polar bears swimming in open water and resorting to eating other food, such as fish. According to Rick Steiner, a marine conservationist at the University of Alaska in Anchorage, "If the ice continues to contract, which seems inevitable, polar bears will become even more nutritionally disadvantaged. The study proves polar bears are in serious trouble."
ANI