[National Geographic Wallpaper] Polar Bear (북극곰) Hudson Bay, Canada  
  1996  
  Flip Nicklin  
 "After spring mating, fertilized [polar bear] eggs do not begin to develop until fall. Thus a female delays giving birth until midwinter. She emerges with her cubs in spring, when she can hunt newborn seals to replenish her fat reserves. For about two and a half years mothers nurse their cubs with milk containing 35 percent fat???a security blanket for the Arctic winter." 
???From "Polar Bears: Stalkers of the High Arctic," January 1998, National Geographic magazine 
 http://www.nationalgeographic.com