The Barents Sea population of a few thousand polar bears is one of the biggest in the world.........However, the Norwegian Polar Institute study(admittedly a small sample of only 29 bears) on the bears reproduction reports that only 10% of female bears birthed cubs in 2014............This, on the heels of a series of warm years resulting in poor sea ice reducing the habitat for the bears to hunt seals..........What cannot be disputed is that Winter ice cover in the Arctic fell to its fifth lowest extent on record in 2014. This continues a long-term trend of decline which is occurring more rapidly than scientists expected and the ice cap could vanish in summer within decades.

http://www.theguardian.com/environment/2014/may/28/polar-bear-cubs-arctic-climate-change

Fewer polar bear cubs are

 being born in the Arctic 

islands, survey finds

Rapid reduction of sea ice level due to climate change hitting population as hunting ground recedes

• Share763
• 12
• inShare8
• Email

• Damian Carrington in Ny-Ålesund, Svalbard
• theguardian.com, Wednesday 28 May 2014 08.02 EDT

A polar bear nurses her two cubs. Global warming is reducing the sea ice level that female polar cubs need to hunt for food. Photograph: Frank Lukasseckfrank Lukasseck/Getty Images

The proportion of polar bear
females around the Arctic islands
 of Svalbard who gave birth to cubs
 crashed to just 10% in 2014, according
to a small scientific survey of the animals.
It follows a series of warm years and poor
 sea ice.

The Barents Sea population of a few
thousand polar bears is one of the
biggest in the world. But global warming
 is rapidly reducing the extent of sea ice
on which the bears hunt seals, their main
food.

The annual survey undertaken by Jon
 Aars and his colleagues at the
Norwegian Polar Institute was conducted
in April, just after cubs and mothers leave
 their dens. They discovered that just three
 of the 29 adult females they tracked and
examined had a cub born that year.

"This is a lower number than we would have
 expected," he told the Guardian. "Typically
 one third or more of the adult females have
cubs from that year." But even this higher
 level is in long-term decline: annual records
dating back two decades show that about half
 of adult females in Svalbard had cubs in the
mid-1990s.

"Maybe this [year's low number] was because
 we have had mild years recently with worse
 ice conditions or maybe it was just a bad
year," said
 Aars, who says it is too early to conclude
the population is collapsing. "It is alarming
 but it is
 quite a small sample, so we have to be
careful.
 But if this is something that repeats itself in
coming years then it will be a concern."

Like a number of polar populations in remote
 regions, scientists do not have enough data
to say whether Barents Sea polar bear
numbers are rising or falling. Aars is confident
 that numbers bounced back after mass killing
of polar bears by hunters was outlawed on
 Svalbard in 1973, and lie somewhere
between 1900 and 3600.

"They were nearly hunted to extinction,"
 he said. "But we are pretty sure there are
 more bears now than in 1973, probably
about twice as many."

As to the future, he said: "With worse and
 worse sea ice conditions we think there
 will come a point when the population will
suffer, but we don't know when that point is."

Winter ice cover in the Arctic fell to its fifth
 lowest extent on record in 2014. This
continues a long-term trend of decline
 which is occurring more rapidly than
scientists expected and the ice cap
could vanish in summer within decades.