Recently I saw a programme about polar bears.  Bears forced to swim too long drown.  A polar bear was shown swimming and looking for land.  It took him five days before he found land.  He was desperately hungry but a colony of walrurses protected themselves so well with tusked males on the outside of the ring that he failed to make a kill and then colony took to the sea.   The bear was so weak and so injured that he could only  lie down on the ice and die.  It seemed such a sad end to all his efforts.