Overview:  The elegant whooping crane, standing at 5 feet tall, holds the distinction of being the tallest bird in North America.  Its loud, bugling call gives this crane its name.  Whooping cranes are also known for their elaborate courtship rituals, in which a pair-bonded male and female perform a beautifully choreographed “dance” of synchronized bobbing, weaving, jumping and calling.  Though never abundant, whooping cranes once ranged throughout most of North America, from the Arctic coast south to central Mexico, and from Utah east to New Jersey and Florida.  Whooping cranes rely on undisturbed prairie wetlands for nesting habitat, feeding on snails, minnows, frogs, larval insects and other aquatic life.  During mid-September, whooping cranes migrate south to the tidal marshes and shallow bays that make up their wintering habitat.  Here, the cranes feed on clams, blue crab and other crustaceans.  Most of the whooping crane populations were displaced as farmers migrated further and further westward, converting their preferred prairie wetland habitats into cropland.  Until the 1920s, unregulated hunting exacted a heavy toll among remnant crane populations, and later, collisions with power lines proved to be the leading cause of crane mortality.  By 1890, most breeding populations of these magnificent cranes had disappeared from the north-central U.S. and, by 1941, only 16 were left in the wild.  These last remaining whooping cranes had found refuge in Wood Buffalo National Park (Northwest Territories, Canada), which is now the last known breeding area for the cranes.  In 1937, Aransas Wildlife Refuge was established in Texas to safeguard the wintering grounds for these whooping cranes.  By March of 1993, the Wood Buffalo crane population had climbed to 136.  In 1975, biologists attempted to re-establish a whooping crane population in Idaho’s Grays Lake National Wildlife Refuge by using sandhill cranes as surrogate parents for whooping crane eggs.  Although many of the young cranes migrated with their adoptive parents and wintered in New Mexico, the project was soon terminated because none of the cranes were able to successfully breed and the population suffered high mortality rates.  Currently, efforts are underway to train captive-bred whooping cranes to migrate using ultra-light aircraft.  To learn more about these attempts at training young cranes, check out Operation Migration at http://operationmigration.durham.net/cranes.htm.  Also, for more general information about the whooping crane, the U.S. Fish and Wildlife Service has a whooping crane biologue at http://species.fws.gov/bio_whoo.html.