The Discovery Channel has brought new attention to the fact that infanticide and cannibalism might be on the increase in Polar Bears as their seal hunting success rate erodes due to Global Warming caused sea ice shrinkage...................While male Polar Bears will kill the cubs of a Female Bear so that she will come back into heat and be open to his advances, Dr. Ian Stirling of Environment Canada(polar bear researhcer for more than 40 years) believes early ice melts are the cause of more cannibalism reports...............As more and more Ice floes melt totally away in summer due to increases in temperatures, hunting for seals becomes more difficult which in turn forces the bears to roam further and settle for less; like sea birds and their eggs

Cannibalism: Is climate

 change causing polar

 bears to eat each other?

allvoices.com

Polar bear eating cub in a sea 
of melted ice with very little food 
available. Photo by researcher Jenny E. Ross

Polar bears were listed as "threatened" 
under the Endangered Species Act 
(ESA) in 2008, following a petition by 
environmental groups. The decision 
was upheld in the D.C. Circuit Court 
early in 2013, after a challenge by the
 State of Alaska, sport hunters and other
 special interest groups.

The polar bear listing represented the
 first animal placed under ESA protection
 solely as a result of climate change, which 
is the cause of melting Arctic sea ice where
 polar bears live and hunt for food.

Cannibalism and infanticide is one of the 
dark sides of nature and it is not uncommon
 in many species, but scientists report an 
increase in polar bears feasting on cubs 
and females in recent years.

Stories of such gruesome activities go 
back to the late 1800s, but challengers 
say there are more sightings now due to 
increased accessibility by researchers 
with cameras. Recent disturbing 
eyewitness accounts reported by Discovery 
Channel told of males taking cubs and
 attacking females in their dens.

One scientist says polar bears, the largest
 of the bear species, do it "just because 
they can."

Dr. Susan J. Crockford is a zoologist, who
 claims polar bears kill each other for a 
number of reasons. Excerpt from her website:

"Male bears kill newborn cubs in the spring 
to bring females into estrus – so that they 
are able and willing to mate again with the 
new male (this only works until perhaps early
 June at the latest); 2) females may eat their
 young (probably at any time of year) when 
they can't get other food; 3) males will kill 
adult females, smaller bears and cubs at 
any time of year and eat them – whether they
 are thin or fat, truly hungry or not – just 
because they can."

Evidently, polar bears are a murderous 
bunch.

Nonetheless, other researchers believe
 starvation is driving polar bears to turn on
 their own as food becomes less reachable
 due to melting ice.

Dr. Ian Stirling of Environment Canada has
 been studying polar bears for more than 40 
years and he believes early ice melts are the 
cause of more cannibalism reports. Ice floes 
melt in summer, with many disappearing 
totally, making hunting for the bear's favorite 
food of seals more difficult, which forces them
 to roam further and settle for less; like sea 
birds and their eggs.

According to an article in The Guardian, 
Stirling recently examined the body a polar 
bear that had been tracked by scientists 
for several years during healthy conditions,
 but was found dead of starvation in southern
 Svalbard series of Arctic Islands near Norway.

"From his lying position in death the bear 
appears to simply have starved and died 
where he dropped," Stirling said. "He had 
no external suggestion of any remaining fat,
 having been reduced to little more than skin
 and bone."

Furthermore, ships have occasionally spotted
 polar bear bodies floating at sea after 
apparently drowning; most likely while 
swimming in search of solid ice after being
 trapped on melting floes. Since drowned
 bears eventually sink to the ocean floor,
 it's hard for scientists to know the extent 
of this problem. Polar bears are massively 
skilled swimmers, but in poor fitness they 
are more vulnerable.

The condition of Arctic sea ice has been 
monitored by satellites for more than 50 years.
 It shrinks in the spring and summer and it 
expands during the late fall and winter. It has
 been measured up to 9 feet deep in places 
and has reportedly decreased by 40 percent 
since the 1970s. In 2012, sea ice levels were
 the lowest in recorded history and scientists 
blame global warming.

Regardless of the "common" claim by many
 to explain cannibalism in polar bears, others 
feel that "common sense" should figure into 
the equation when polar bears are facing a 
mortal scarcity of food due to a melting habitat.

Many experts feel polar bears could be 
virtually extinct in the next 50-100 years if 
climate change stays on its current path.