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Between 1850 and 1941, the whooping crane population dropped from an estimated 1500 birds to a low of perhaps 20. Today, thanks to cooperative, international conservation efforts, more than 415 whoopers thrive in North America. While these numbers are still low, scientists believe that if habitat conservation, species protection and reintroduction efforts continue, whooping cranes will be able to maintain viable populations and continue moving away from the brink of extinction.
There are three main populations of whoopers in North America. Each year, the sole surviving wild population journeys 2,400 miles across the heart of North America, from nesting grounds at Wood Buffalo National Park in Canada’s boreal forest to winter havens in Aransas National Wildlife Refuge on the central coast of Texas. Along the way they rely on prairies and wetlands, such as the Platte River in Nebraska and the Cheyenne Bottoms in Kansas, for stopover sites.
Ensuring the Survival of a Species
Though the wild population that breeds in the boreal is considered sustainable because of its numerous breeding pairs, it is still at risk. Because all the birds of this surviving wild flock breed in the same area, they are vulnerable to events, such as oil spills or wildfires that could potentially wipe out more than half the population of North American whooping cranes in a matter of days or weeks. To help ensure the long-term survival of whooping cranes, many groups have worked to protect and reintroduce the species in other parts North America through captive breeding and reintroduction programs.
Two other flocks of whoopers have been established in North America. Both populations are products of successful captive breeding and reintroduction programs and are considered experimental because they are not yet self-sustaining.
One group of whoopers is sedentary and lives year round at Florida’s Kissimmee Prairie. The other flock migrates – with fledgling chicks led by volunteers from the Whooping Crane Conservation Association flying ultralight aircraft – from Wisconsin’s Necedah National Wildlife Refuge to the Chassahowitzka National Wildlife Refuge on Florida’s Gulf Coast. Scientists are working to introduce enough birds to the flyway to establish a self-sustaining flock of at least 25 breeding pairs.
Nature picture credits (left to right):Whooping cranes in water © Photos.com; Whooping crane close-up © Peter Llewellyn.
