BLACK RHINOCEROS:  The black rhinoceros can grow up to twelve feet long and six feet high.  Weighing about 3,000 pounds, it is the second largest land mammal.  Over the last three generations, the rhino population has declined by 80% and it is still falling.  The black rhinoceros is the most aggressive of the rhino family, and can charge at over 35 mph; plowing through anything in its path.  It is poached for its large ivory horns.