As the tallest flying bird in North America, the whooping crane is easily recognized, sporting a very long neck, legs and bill. The crane is snow-white, with red and black colouring on the crown and around its greyish beak. The legs are grey-black, as are the wing tips, which can usually be seen only when the bird is in flight. It is one of the few animals whose eyes are blue when it is young and turn yellow as it matures. During flight, the whooping crane extends its neck forward and its legs straight back, a profile that sets it apart from other large white birds.
The whooping crane exerts a minimum amount of energy when airborne, using its giant wingspan to fly like a glider. It relies on thermal updrafts to push it spiralling upward, then glides back down to as low as 70 metres above ground, only to spiral up once again.
Habitat and behaviour
Its common name comes from the “whooping” call it makes. When it feels threatened, is showing aggression or is courting, the crane stands straight up, throws its head back, with its beak pointing skyward, and utters its high-pitched call.
The whooping crane generally mates for life. During courtship, the female begins the back-and-forth “whooping” sequence, calling out twice for every lower-pitched male call. The male and female then engage in an elaborate dance that includes bowing, running, wing flapping and impressive metre-high jumps. Not only is the dance an important part of courtship, but it is also seen as key to the whooping crane’s motor development and as a way for the cranes to relax.
The whooping crane builds its nest out of bulrushes and cattails in boreal wetland complexes of marshes, shallow ponds, small creeks and patches of wooded terrain and shrubs. Its winter habitat includes grasslands, freshwater ponds, tidal flats and tidal marshes. As an omnivore, it enjoys a varied diet that includes berries, insects, snails, minnows, frogs, snakes, mice and voles in summer, waste grain during migration and clams, crabs and wolfberry in winter.
Once numbering in the thousands across the Great Plains of North America, the whooping crane came very close to extinction in the mid-20th century. In 1941, there were only 21 known living birds. Now, thanks to protection, captive breeding and reintroduction programs, the population is recovering. There are currently three populations of whooping cranes in North America: the Wood Buffalo/Aransas flock, which is the only wild flock; and two reintroduced populations, the eastern migratory flock and the Florida non-migratory flock, in and around Kissimmee Prairie. The Florida population, however, is not self-sustaining.
The whooping cranes that nest in Wood Buffalo National Park, on the border of Alberta and the Northwest Territories, migrate in the fall through Alberta, Saskatchewan and, occasionally, Manitoba, staging in Saskatchewan en route to their wintering grounds at Aransas National Wildlife Refuge, on the Texas coast. Using ultralight aircraft, researchers have taught the eastern migratory population to migrate from Necedah National Wildlife Refuge, in Wisconsin, to Florida’s Chassahowitzka National Wildlife Refuge.
In 2009, there were 382 whooping cranes living in the wild and 152 in captivity. The breakdown of the non-captive population is: Wood Buffalo/Aransas 247; eastern migratory 106; Florida non-migratory 29.