By the end of September, the whoopers leave for the 4,000 km flight south to the Aransas National Wildlife Range in Texas. By gliding on wind currents, they can stay aloft for 10 hours and cover up to 750 km. Whoopers are the tallest of all birds in North America. An adult male stands 1.5 m tall, weighs as much as 7.5 kg, and has a wingspan up to 2.5 m wide. Despite their size, cranes average a flight speed of about 45 km-h.
Cranes eat snails, larval insects, leeches, frogs, minnows, small rodents, and berries.
They may scavenge dead ducks, marsh birds or muskrats. During migration, they stop to eat aquatic animals, roots of plants and waste grain in stubble fields. In Texas, they eat shellfish, snakes, acorns, small fish and wild fruit. Whooping cranes mate for life. In early spring, adults display elaborate courtship rituals, bobbing, weaving, jumping and calling with their mates.