Title:    "Alaska Aurora Polar Bear Watch"

©   Alaska Artist Dianne Roberson

Polar Bear | Northern Lights | Alaska        

Stock #  DA 077

 Digital Art   |   Color Print

Size:  20" w by 16" h     $ 45.00                            

Size:  14" w by 11" h    $ 35.00                          


Polar bears have longer necks, and smaller heads and ears, compared to other species of bears.  The body of a polar bear is
large and stocky, similar to that of a brown bear, except it lacks the shoulder hump.  Polar bear skin is black and the fur is
actually clear, lacking in pigment.  The white appearance is the result of light being refracted from the clear hair strands.  Their
coat is made up of a thick outer layer of fur on top of a dense undercoat.  The forepaws are broad and webbed to assist in
swimming and walking on thin ice.  The soles of their feet are furred for insulation and traction while walking on ice and snow.  
Polar bears are usually solitary, with the exceptions of mothers with cubs or groups of polar bears feeding on whale
carcasses.  Males are females are also found together when paired during mating season.  Bears may also come into
competition with one another when a seal kill attracts other bears looking to scavenge.  In instances where bears encounter
each other, the smaller bear will tend to run away.  A female with cubs, however, will charge males that are much larger to
protect her young or a kill that they are feeding on.  Polar bears conserve their energy as much as possible, either sleeping,
lying, or waiting (still hunting).  The rest of their time is spent walking, swimming as they travel across sea ice, stalking prey, or
feeding.  Humans and other polar bears are the only predators of the polar bear.  Male polar bears may prey on cubs if they
come into contact.  Females with cubs tend to avoid other bears for this reason.  Polar bears do not hibernate like other bears
and do not den in winter unless they are pregnant females.   A pregnant female will find a den or excavate her own to give birth
to her cubs, going in the den in November or December and emerging with cubs for the first time in March or April.  Polar
bears will travel as much as 600 miles north and south, as the ice melts and freezes.  During summer, bears may remain on
islands or coastlines with land fast ice, drift on ice flows, or get stranded on land where they are forced to endure warm

Polar bears are carnivores.  In summer, they may consume vegetation out of necessity but gain little nutrition from it.  Their
primary prey are ringed seals.  Bears often leave a kill after consuming only the blubber because the high caloric value of
blubber relative to meat is important to bears for maintaining an insulating fat layer and storing energy for times when food is
scarce.  Polar bears do not store or cache unconsumed meat as other bears do.  Polar bears have two hunting strategies.  
Still-hunting is used most often, involving finding a seal's breathing hole in the ice and waiting for the seal to surface to make
the kill.  When a bear sees a seal basking out of the water, it will use a stalking technique to get close and then make an
attempt to catch it.  One stalking technique is crouching and staying out of sight while creeping up on the seal.  Another
technique is to swim through any channels or cracks in the ice until it is close enough to catch the seal. Using this technique,
a bear may actually dive under the ice and surface through the breathing hole in order the surprise the seal and eliminate its
escape route.  Feeding usually occurs immediately after the kill has been dragged away from the water.  Polar bears consume
the skin and blubber first and the rest is often abandoned.  Other polar bears or arctic foxes then scavenge these leftovers.  

Females are sexually mature when they are three to six years old, males reach sexual maturity at four to five years.  The
breeding season for polar bears is March through May.  They have delayed implantation, as do many mammal species, which
allows females to expel fertilized eggs if their body condition is too poor to support themselves and fetal growth.  If body
condition is good, a female will become pregnant in fall.   Cubs are born in November or December in snow caves called
maternity dens.  After feeding heavily in April or May, females that have mated dig a den in late October or early November.
Most choose den sites in snowdrifts along mountain slopes or hills near the shore. Some dig their dens in snowdrifts on the
sea ice.  Twins are common, although single births of one cub are becoming more common as females face increased
stress due to loss of sea ice habitat and valuable hunting time.

When cubs are born, they are 12 to 14 inches long and weigh a little more than one pound.  Their eyes are closed, they have
no teeth, and are covered in very short and soft fur.  They depend on their mother completely for food and warmth.  While in the
den, a female does not eat or drink.  Cubs nurse on their mother's milk, which is over 30% fat, and grow very quickly.  By March
or April, females are ready to begin coming out of the den with their cubs for very short periods.  The do not stay out for long or
travel far at this time, due to the cubs' lack of mobility.  They gradually range farther from the den site with their mother, who is
eager to get back on sea ice to hunt seals before summer ice melt.   Females usually give birth for the first time after age six,
and cubs stay with them for up to three years while they learn their hunting and survival skills from their mothers. This gives
polar bears one of the slowest reproductive rates of any mammal, typically producing only five litters in their lifetime.

Northern Lights

Also know as the Aurora Borealis, these lights are best viewed in the cold dark winter months in Alaska.   The beautiful blaze
of the
Northern Lights, or Aurora Borealis, begins when energetic electrically charged particles accelerate along the magnetic
field lines into the upper atmosphere, where they collide with gas atoms, causing the atoms to give off light. The air lights up
rather like what happens in a fluorescent light tube.  The colors reflect gases, the most usual yellow-green color coming from
oxygen. Red coloring is also due to oxygen with a contribution from nitrogen and violet is due to nitrogen. The charged
particles originate from the sun, and it is the “weather” conditions on the sun that decide whether or not we will see the aurora.

Print Information

The website address will not be printed on your print.  This print is treated with an ultra violent protective coating.  It will be
rolled and inserted into a mailing tube if ordering a glossy paper print, if ordering stretched canvas this print will be boxed.   
The print  will be mailed first class by the U.S. Postal Service and insured.
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Phone:  1-404-462-4615
Inside Alaska phone:  1-907-775-4229

Alaskan Art by Alaskan Artist Dianne Roberson
Copyright  2006        ©   Dianne Roberson    All rights reserved.