Reproduction
Male and female white-naped cranes mature sexually at about 3 years of age, but frequently will take longer to form pair bonds and successfully reproduce. As with all cranes, white-naped cranes form lifelong monogamous pair bonds.

The clutch is normally two eggs that are olive-green in color with brownish blotches. Both sexes take part in the incubation for 30-33 days, with the female usually sitting the greater amount of time. At the zoo, our female usually lays eggs during the last week in April. She might re-clutch in June if the first clutch fails. While one bird is incubating, the other is frequently standing guard over the territory of the enclosure. This behavior, which may lead to aggressive attacks, is directed at anyone getting too near the nest—especially the keepers.

Life Cycle
Both chicks survive in approximately 30% of the nests. A chick begins to forage soon after hatching. The family remains together through migration and winter, whereby the immature bird learns the migration route and wintering areas. During the non-breeding season, white-naped cranes are more social and band together in loose flocks, often with other crane species, in optimal habitat. In early spring, adults return to their breeding territories and separate into breeding pairs.

Courting Dance
White-naped cranes are renowned for their spectacular and elaborate courtship dances that strengthen bonds between mated pairs. During this graceful display, birds circle each other while leaping and calling, head-bobbing toward one another and bowing with spread wings. Grasses, sticks or feathers are frequently tossed in the air. These dances can be observed throughout the year as the birds continually reinforce their pair bonds.

When I Call You
One way of telling male and female white-naped cranes apart is when the birds are giving their loud unison calls. As both birds point their bills to the sky, the female starts the call. The male raises part of his wing over his back and joins the female in a duet. The two birds call back and forth for about 10 seconds. These calls are used to reinforce their pair bonds and to defend their territory. This duet can often be heard at Woodland Park Zoo, giving notice to other white-naped cranes in the vicinity to stay out of their territory.

The zoo’s white-naped cranes can be seen near the Temperate Wetlands exhibit in the Temperate Forest. Demoiselle cranes can be viewed at the Asian Marsh exhibit in Tropical Asia.

Seven of the 15 species of cranes are listed as threatened or endangered. The white-naped crane is listed at endangered.* The destruction of natural habitat on breeding grounds, in wintering areas and along migration routes is having a devastating effect on crane and other migratory bird populations. An example of habitat loss is the Three Gorges Dam on the Yangtze River in China which is currently under construction. This hydro project will have detrimental results on natural water flows, changing the flow of nutrients required by suitable vegetation for wetlands in which cranes overwinter. A 1996 IUCN report estimated that only 4,900-5,300 white-naped cranes remain in China, Japan and South Korea.

With several other zoos, Woodland Park Zoo is participating in the Association of Zoos & Aquariums' (AZA) Species Survival Plan (SSP) for white-naped cranes. SSPs include conservation-oriented research, breeding of selected animals to maintain genetic diversity and cooperative educational efforts. As an example, fertile white-naped crane eggs have been sent by other zoos to the Khinganski Nature Reserve in Russia. Reserve staff have been trained by SSP staff to raise these cranes in captivity and eventually release them back into the wild.

In 1977, several wild caught birds came to the International Crane Foundation in Baraboo, Wisconsin from the People’s Republic of China. In 1982, our male was hatched by two of these birds, and our female was hatched from a different pair of wild-caught birds in 1987. As both sets of parents represented good lineage, these birds were paired to create a new genetic line. So far, we have had these birds nest each year. Unfortunately, all the eggs have been infertile.

How You Can Help!
The effort to save threatened and endangered migratory birds requires cooperation and support at the international, national, regional and individual levels. You can help in this cause. Join and become active in Woodland Park Zoo and other conservation organizations of your choice. Recycle forest products. Eliminate or reduce pesticide use. Let your elected representatives know your views about conservation of migratory birds and their wild habitats.

Contact Woodland Park Zoo at webkeeper@zoo.org to find out about ways you can support conservation programs at the zoo. Discover more about endangered cranes by calling the International Crane Foundation at (608) 356-9462 or at their Web site. Learn other ways you can help conserve wildlife and the habitats they require for survival by visiting our How You Can Help page.

Sources and Suggested Reading
Johnsgard, Paul A. 1983. Cranes of the World. Indiana University Press, Bloomington, IN. 257 p.

For Kids!
Horn, Gabriel. 1988. The Crane. Crestwood House, Mankato, MN. 48 p.

More References

*Woodland Park Zoo identifies an animal or plant endangered if it is listed as endangered (in any part of its range) on the federal list of Endangered and Threatened Species, or if is listed on Appendix 1 of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).