Biologists estimate that there were between 700 and 1,400

whoopers alive in 1865. Their numbers dropped rapidly, however, and by 1890 the whooping crane had disappeared form the heart of its breeding range in the north central United States. By 1938, only two small flocks remained, one non-migratory flock in southwest Louisiana, and one migratory flock that nested in Canada and wintered in Texas.

The migratory flock was reduced to 15 birds in 1941, with an additional six whooping cranes surviving in the Louisiana flock. By 1949, severe weather had decimated the Louisiana population, leaving only the small migratory flock. Whooping cranes were on the brink of extinction.

The two most important factors that contributed to the decline of whooping cranes were habitat loss and unregulated hunting. As European settlers expanded westward, they drained marshes and plowed prairies for agriculture, destroying much of the birds’ nesting habitat. Many remaining habitats were close to human disturbance, a stress to which this shy and secretive species was unable to adjust. As the number of whooping cranes declined, hunters, hobbyists and museum collectors scrambled to acquire the rare specimens and eggs for their collections.

Only one small flock of whooping cranes trod between survival and extinction. Ambitious recovery efforts were needed to save the species. Projects to protect this wild flock and to create new populations were put in motion and began the whooping cranes’ long journey to recovery.

Hope for the survival of whooping cranes was held in the lone wild flock that migrated from the wilderness of Canada to the Gulf coast of Texas each winter. Their wintering grounds were protected in 1937 with the creation of the Aransas National Wildlife Refuge. (The Refuge was originally established for migratory birds, which included the whooping cranes. It was not established specifically for whooping cranes.) However, their breeding grounds, 2,500 miles to the north, remained a mystery until accidentally discovered in 1954 by a fire crew flying over Wood Buffalo National Park in the Northwest Territories of Canada.

The discovery of the species’ only remaining breeding grounds opened new options to save these birds form extinction. Because whooping cranes lay two eggs per clutch but usually only raise a single chick, it was thought that one egg could be removed from each nest without decreasing the productivity of the wild flock. Egg collection occurred during 1967-1996. The eggs became the foundation for future release programs in North America.

Due in part to habitat protection and hunting restrictions, this “remnant flock” has made a dramatic recovery. More than 210 whooping cranes now migrate between Canada and Texas.
Captive breeding efforts are taking place at the International Crane Foundation, Patuxent, and the

Calgary and San Antonio Zoos. Captive breeding and reintroduction efforts have become possible with the development of better chick-rearing techniques.

In 1975, the U.S. Fish and Wildlife Service and Canadian Service began placing whooping crane eggs in sandhill crane nests at Grays Lake National Wildlife Refuge in Idaho. The sandhill cranes hatched and raised the whooping crane chicks, and the chicks learned the migration route from their surrogate parents. However, when the whooping crane chicks reached breeding age they did not pair with other whooping cranes. Instead, they pursued sandhill cranes as mates. The chicks had learned their species identity from their sandhill crane foster parents. This improper “imprinting” led the birds to identify with the wrong species. The project was terminated in1989 and by 2002, no more whooping cranes remained in the region.

Reintroduction efforts for this new flock of whooping cranes began in 1993. Up to 20 chicks are released to central Florida each year to begin a new population of non-migratory whooping cranes. These cranes are never taught a migration route. Over 200 cranes have been released to the Kissimmee Prairie, Florida. As these reintroduced birds mature, crane pairs are forming and some pairs are defending territories, building nests and laying eggs. In 2002, a pair from this flock hatched and fledged the first wild whooping crane chick in the U.S. since 1939. Breeding success is expected to continue in coming seasons.

Another reintroduction effort is aimed at restoring a migratory flock of whooping cranes to eastern North America. It is a project by the Whooping Crane Eastern Partnership (WCEP), a team of non-profit and governmental organizations whose founding members include the International Crane Foundation, U.S. Fish and Wildlife Service, Wisconsin Department of Natural Resources, Operation Migration, U.S. Geological Survey, Natural Resources Foundation of Wisconsin, National Fish and Wildlife Foundation and many other dedicated partners. Young chicks are being raised in wetlands during the summer at Necedah National Wildlife Refuge in Wisconsin.

In the fall, Operation Migration leads the young cranes on migration with ultralight aircraft to follow behind an ultralight to Chassahowitzka National Wildlife Refuge in Florida. The chicks learn the route during their first trip south. They are then able to make the return journey in the spring on their own. In October 2001, the first flock of reintroduced cranes departed Necedah NWR and began the 48-daym 1,218-mile migration to Florida. The flock spent the winter on the Gulf coast of Florida at the Chassahowitzka NWR. The birds were monitored by biologists throughout the winter. The flock initiated spring migration unaided by the ultralight on April 9, 2002. Their spring migration was comparatively swift (only 11 days from Florida to Wisconsin). Without the ultralight, the cranes are able to fly more efficiently by riding thermals and soaring rather than expending energy flapping their wings to keep up with an airplane.

Recovery Plan Goals are to 1) Maintain a minimum of 40 nesting pairs in the Aransas –Wood Buffalo flock, and 2) Establish two additional separate, self-sustaining wild populations of whooping cranes, with a minimum of 25 nesting pairs. The long-term recovery goal for whooping cranes is to establish a self-sustaining population of a minimum of 1,000 whooping cranes in North America by the year 2035. WCEP’s efforts towards this goal are to establish 25 breeding pairs form 125 birds released in the Eastern Migratory Flyway by 2020, with 18-20 chick introduction each year.

Reference: “Whooping Cranes: North America’s Endangered Legacy” by International Crane Foundation and Wisconsin Department of Natural Resources. 2003.