Title:     "Alaska Aurora Night Stalker"

© Alaska Artist Dianne Roberson

Polar Bear | Northern Lights | Alaska        

Stock #  DA 091

Digital Art   |   Color Print

Size:  20" w by 16" h     $ 45.00                                                 

Size:  20" wide by 16" High     $175.00
    Color Print on stretched canvas                                   

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 weather.

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
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.