Polar Bear Ice Ursus maritimus Ursidae POBE URSMAR Mammal Predator Behavior dangerous fur white cold snow global warming pack ice floe threatened melting melt arctic Arctic Zone North Pole polar region marine sea drift landscape icescape behavior symbol symbolic allegorical emblematic sad thoughtful thought-provoking alarming worrying concerning Svalbard hole waiting foraging lying horizon impressing resting hungry exhausted solitude lonely solitary animal loner Norway July Summer Spitsbergen cavity summer Rhine-Westphalia Europe pale pile pole stake animals Spitzbergen