Other Species in Trouble

Arctic foxes aren't the only species in the tundra being affected by warming.  This page lists several others ways in which warming has impacted arctic species.

Grizzly Bears

"I'm hungry!"
http://grist.org/climate-change/
why-climate-change-is-like-a-grizzly-bear/

A necessary source of food for grizzly bears are nutrient rich seeds from the white-bark pine trees.  They are especially important to the bears as they prepare for hibernation.  However due to recent warming, this supply of food has been almost entirely lost.  Mountain pine beetles are now flourishing in white-bark pine forests, causing a significant increase in pine mortality rates.  The recent shifts of the beetles into these forests has been attributed to warming events that allowed the beetles to move north, devastating the white-bark pine forests.  This change in food availability has taken a significant toll on grizzly bear populations.

Polar Bears

"Where did the ice go?"
http://johnpaulus.com/blog/2011/07/28/global-warming
-researching-suspended-for-misconduct-integrity-issues/ 

We've all heard concerns about the polar bears, but do you know what exactly is causing the decline in population?  Polar bears' primary source of food are seals.  In order to catch them, the bears rely on a clever technique that requires ice.  Seals cut holes in the ice, so that every 5-15 minutes they can surface to breathe.  Polar bears use their keen sense of smell to find these holes and wait for a seal to surface.  As the arctic warms, polar bears have to travel further and further north to find enough ice to hunt for seals.  The recent loss of ice in the arctics has correlated with a significant drop in the population of polar bears.

Caribou (AKA reindeer)

"All i want for Christmas is... more snow!"
http://dels-old.nas.edu/climatechange/arctic.shtml 

Caribou population growth is also destined to decline.  A possible explanation for this is a loss in its primary source of food during the winter.  During times of heavy snow, caribou will dig through patches of snow to get at the lichens that grow underneath.  Due to recent warming events, snow is melting sooner, forcing lichens to compete with other shrubs that don't survive well during snow.  When winter comes, lichens are then harder to find, forcing caribou to find food elsewhere.  If populations continue to decrease, Santa will have to find a new mode of transportation for his sleigh.