GENUS & SPECIES
• Dances with its partner and other cranes, in rituals that extend beyond courtship Into everyday life
• Graceful but raucous ballet seems sometimes to be performed out of sheer joy
• Japan’s revered tancho, or “bird of happiness,” this affectionate crane forms a lifelong pair bond and is upheld as a symbol of fidelity in marriage
WHERE IN THE WORLD?
Almost all cranes “dance” to their partner, but few take their “fun” so seriously as the Japanese crane, which skips and frolics through almost every week of its life.
The Japanese crane lives in freshwater wetlands close to lakes and rivers. It favors marshy moorland and damp, sparsely wooded areas, where dense beds of tall reeds or grasses screen its nest.
About 600 cranes live on the Japanese island Hokkaido, one-third of the entire world population.They survive severe winters by moving to farmland, where they’re artificially fed. Cranes in Siberia and China migrate south to spend winter on coastal marshes, mudflats and paddy fields.
For safe roosting, it prefers to stand in shallow water on submerged sandbars in rivers.
Field fare Damp grassland provides shelter and nest material.
The Japanese crane’s plight began in 1868, when westernization followed the ousting of the Shoguns (feudal governors who had long protected the tancho). Hunting controls disappeared; by the early 1900s European hunters shot the crane into presumed extinction. When 20 survivors were discovered in 1924, rescue efforts began; the crane’s population now stands at about 1,800 birds. It’s still listed as vulnerable and, although cherished by the Japanese nation, remains threatened by habitat loss, pesticide use and fires.
Crane designs feature in Japanese marriage ceremonies to symbolize happiness, long life and fidelity.
In feudal Japan, Shogun leaders let only one crane be killed a year, as a gift for the Emperor’s feast.
A Tender two-step Cranes form and strengthen lifelong pair bond with dances.
Cranes pair for life, reinforcing the bond with dancing. Flocks disperse early in the breeding season and pairs take up their nesting territories, which may be several miles apart.
Nest-building is a joint effort. The male brings plant stems to his mate, who builds a mound 12″ high and 5′ across. Nests are usually sited in, or at the edge of, shallow water.
Both sexes incubate and rear the chicks, which leave the nest in three days of hatching. The adults are diligent parents, bringing tiny morsels, such as insects, to their chicks. They supply food for several months, until the chicks are capable of feeding themselves.
Tawny down is replaced by feathers after eight weeks.
The crane dances almost year-round and at any age; its antics play a key role in almost every aspect of its life. Its routines are used to attract mates, stake out nesting territories, greet other members of the flock and warn of possible danger: Frequent and spectacular dances are performed on snow-covered fields in late winter, when a solo display may inspire a flock into a frenzy.
During their autumn migration, the Asian mainland flocks soar high or fly in V-formation, with a characteristic wing action in which the powerful downbeat is followed by a quick upward flick. The Japanese crane becomes flightless during the summer molt of its wing feathers; during this time it hides in thick cover while the new quills grow and spread into feathers.
Graceful and lively, the dance follows no set routine, but the birds usually start by lifting their heads and bugling loudly.
One crane curtsies, while its mate accepts the compliment. The bowing bird may hold a stick or reed, which it tosses into the air as it rises again.
Some postures reveal why “craning” describes awkward movements of the human neck. Dancing birds also make much play with their wings.
Joyous jumps are performed frequently during the display. When dance fever spreads, an entire flock may hop and skip.
FOOD & FEEDING
Sharp spear The crane uses its long bill to stab at vegetation and small prey in shallow marshes and rivers.
The crane’s powerful bill and long reach of its flexible neck let it exploit a range of food on land and in water: It obtains much of its food by digging in mud, probing deep for grubs, worms and other invertebrates. It also forages for vegetation, roots, seeds and buds.
The crane captures fish, frogs, snakes and flying insects with a rapid jab of its bill. It also snaps up small mammals and ducklings or other young birds in a similar manner When faced with prey items too large to swallow whole, the crane shakes them vigorously in its bill to break them into more manageable pieces.
For the cranes resident on the island of Hokkaido, the staple diet switches in winter to corn, provided at special feeding stations by farmers and conservationists.
All tall and elegant, cranes vary greatly in size. Smallest is the demoiselle crane of Asia and Africa, which stands half the height of the Japanese crane. With its golden topknot, the 3′-tall crowned crane is a striking inhabitant of the African savannah. Up to 4′ tall, the sandhill crane lives in Siberia
and North America. Like the Japanese crane, it has a red crown.
|Sexual Maturity||3-4 years|
|Mating 1 season||March-May|
|Number 1 of Eggs||2|
|Incubation . Period||4-5 weeks|
|Fledging Period||11-13 weeks|
|Breeding Interval||1 year|
|Typical Diet||Plants, grain,
roots, insects, reptiles and small mammals
|Lifespan||Up to 25 years|
• The Japanese, or Manchurian, crane is one of 14 crane species; seven are threatened. The rarest (and most closely related to the Japanese) is North America’s whooping crane (below), with a population of about 300.