Reproduction
Male and female red-crowned cranes mature sexually at 3 to 4 years of age, but frequently will take longer to form pair bonds and successfully reproduce. As with all cranes, red-crowned cranes form lifelong monogamous pair bonds.

Egg-laying occurs in the early morning hours and two eggs are laid two to four days apart. The clutch is incubated for 29-31 days by both birds. The female does most of the incubating, with the male on the nest during the middle part of the day.

Life Cycle
Mainland red-crowned cranes breed and nest in northern Manchuria and southeast Siberia. Breeding takes place in late March and April, with the first eggs arriving in late April. As winter approaches, the mainland population migrates to South Korea and China. Those migrating to South Korea arrive in mid-November to early December. They leave South Korea in March. Those birds that winter in China arrive in late October to mid-November, and leave China in March.

Beautiful Dancers
Red-crowned cranes are renowned for their spectacular and elaborate courtship dances. During these graceful displays (usually performed in pairs), 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.

Singing a Different Song
Unison calling between males and females serves three distinct functions: formation and maintenance of pair bonds; territorial advertisement; and competitive or combative signaling. Unison calling also helps distinguish males from females. The unison call is usually initiated by the female. For each male call that follows, females from the mainland population of red-crowned cranes respond with two notes. Hokkaido red-crowned crane females answer with three to four call notes.

The zoo's red-crowned cranes can be seen adjacent to the Temperate Wetlands exhibit in the Temperate Forest. Other Asian cranes in the vicinity are the white-naped cranes. 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 red crowned 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. Specific threats for the red crowned crane are drainage of wetlands and reclamation of wintering grounds for agriculture. In 1996, the wild population estimates for the red crowned crane in North and South Korea and Japan was 1,700-2,000 birds.

With several other zoos, Woodland Park Zoo is participating in the Association of Zoos and Aquariums' (AZA) Species Survival Plan (SSP) for red crowned cranes. SSPs include conservation-oriented research, breeding of selected animals to maintain genetic diversity and cooperative educational efforts. As an example, fertile red crowned 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.

The pair of birds on exhibit at Woodland Park Zoo were received in 1992 from Kobe Zoo, Japan. These birds are on our high priority list to breed. This pair have successfully reproduced the last two years and have added to the genetic diversity of the captive population.

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.

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
Grooms, Steve. 1992. The Cry of the Sandhill Crane. NorthWord Press, Minocqua, WI. 160 p.

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.

Voeller, Edward. 1990. The Red-Crowned Crane. Dillion Press, Minneapolis, MN. 59 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).