Red-Crowned Crane

strike at fish or other slippery prey by extending the neck, much like herons. They usually tear large prey apart rather than swallowing it whole. The diet is highly omnivorous: fish, amphibians, snails, crabs, insects, shrimp, small birds, and rodents, and one authority calls the species perhaps the most carnivorous crane. Adults need about 750 g (26 oz) of food per day. In winter, plants matter more: wintering birds in Japan depend on rice, grass seeds are another key food, and in cold, snowy weather they mainly eat rice gleanings from paddy fields. They feed in wet grasslands, cultivated fields, shallow rivers, and lake shores.

Red-crowned cranes handle winter in two ways. A resident population in eastern Hokkaido moves only about 150 km (93 mi) to its wintering grounds, while mainland birds make long migrations, leaving wintering areas by February, settling on territories by April, and departing breeding grounds in October and November. Mainland breeders nest in Russia’s Far East, northeast China, and occasionally northeastern Mongolia, then winter on the Korean Peninsula and in east-central China, using paddy fields, grassy tidal flats, and mudflats. Winter counts in 2020 found over 3,800 birds: about 1,900 in Japan, over 1,600 in Korea, and about 350 in China. The Japanese and Korean groups have grown in recent decades, but the group wintering in China has declined rapidly.

The red-crowned crane is a long-lived bird. Wild birds are assumed to live 20 to 30 years, and the oldest known wild bird in Hokkaido died at 35. Captive birds can reach up to 65 years, though the oldest recorded captive crane, Mali, died at 46 at Kushiro Zoo, and another, Momo, was 45 at Tama Zoological Park. That reputation shapes culture across East Asia. In Taoism the crane symbolizes longevity and immortality, and the Japanese tanchō is said to live 1,000 years. A pair appears on the reverse of the Series D 1,000-yen note. The Ainu revered it as the god of wetlands. In Korea it stands for longevity, purity, and peace, appears on the 500-won coin, and is the symbol of Incheon.

Red-crowned cranes are famous for dancing. Courtship dances include circling, leaping, calling, head-bobbing, bowing with spread wings, and tossing grass, sticks, or feathers, and birds dance throughout the year, thought to express excitement. Dancing comes with duets: pairs throw their heads back and call in unison, and the main duet part always begins with a long male call. Duets help form and maintain the pair bond and also signal territory and aggression, and one pair’s duet often triggers other pairs to call. Within a flock, duet displays appear to signal joint defense of resources. The species is monogamous and believed to mate for life, breeding begins at about 3 to 4 years old, and mating and egg-laying are mostly restricted to April and early May.

During the breeding season, a red-crowned crane pair defends a territory of 1 to 7 sq km (0.4 to 2.7 sq mi), often reusing it year after year. The female chooses the nest site, both sexes build, and nests sit on wet ground or in shallow water no deeper than 20 to 50 cm (8 to 20 in). Unison calls help signal ownership. In winter the birds are more social, roosting in groups of up to 80. Even then they keep at least 2 to 3 m (6.6 to 9.8 ft) from one another to avoid pecking, and violators may be attacked violently. Their social life is flexible, but with limits: close company is tolerated, and crowding is not. Birds also wintering near feeding stations gather where food is provided.

Most red-crowned crane nests hold two eggs, though one to three have been recorded, and eggs may be laid two to four days apart. Both sexes incubate for at least 30 days and both feed the chicks. Zoo accounts add detail: the female does most of the incubating, including the night shift, while the male sits on the nest in the middle of the day. Hatchlings weigh about 150 g (5.3 oz) and wear yellow down for two weeks. By about 3 months they follow their parents into the marshes, and they fledge about 95 days after hatching, though one source says about 2.5 months. Young stay with their parents for about 9 months, guided and fed by both adults through a vulnerable first stage of life.