James L. FranklinChicago, Illinois, United States The Steller’s Sea eagle (Haliaeetus pelagicus) handily outsizes the national bird of the United States, the Bald eagle (Haliaeetus leucocephalus). Steller’s Sea eagle is the heaviest eagle in the world: females weigh from thirteen to twenty pounds and males weigh between eleven and fifteen pounds. Its seven-foot wingspan is…