Heralds of Happiness

Article excerpt

Tall, distinguished inhabitants of wetlands and grasslands, cranes elicit attention with their exuberant dances, trumpetlike calls, and transcontinental migrations.

For the Japanese and Koreans, cranes and traditional symbols of the happiness, long life, and prosperity. Birth and wedding ceremonies are often decorated with the crane--which folklore suggests live for 1,000 years, riding the back of a turtle that lives 10,000 years. The wisdom and longevity of cranes have also figured in the beliefs of Buddhists, who protected the birds over the centuries by establishing and maintaining sanctuaries for wintering flocks.

Westerners, on the other hand, harbor a mix of views about cranes. To some, the birds appear stark and awkward; to others, however, cranes are magnificent and warrant our administration and protection. Whatever the perception, no one can deny that this creature is endowed with extremes of length: A crane stalking its territory appears to all legs, neck, and bill.

The long legs allow the bird to hunt the shallow and moderately deep waters of marshes and swamps. And the crane needs its lengthy, flexible neck and long bill to reach down when procuring food. The body length is accentuated in flight, when the bird hold its neck and legs outstretched horizontally and supports itself with an airfoil of long, broad wings.

An ancient family

Cranes are an ancient family, dating back to the Eocene period of about 40 million years ago, and they seem to have changed little since their first appearance. Their closet relatives are the rails, limpkins, bustards, and trumpeters, all of which are placed in the order Gruiformes.

The 15 extant species of cranes are relatively long-lived, monogamous birds, found on all of the word's continents except South America and Antarctica. Asia boasts nine species and Africa four, while Europe, Australia, and North America have two species each. The North American species are the sandhill crane (Grus canadensis) and the whooping crane (G. americana).

Cranes are comparatively large birds: the whooping Siberian (G. leucogeranus), and sarus (G. antigone) are all five or more feet in length, with equally wide wings. Even the smallest crane, the dainty demoiselle (Anthropoides virgo), is nearly three feet long. Each crane also has an exceptionally long, coiled windpipe, which enables the bird to produce trumpetlike calls that can be heard miles away.

Crane color seems to be a function of habitat and behavior. White cranes nest in the vast open wetlands and high tundra of Eurasia and North America. Their shiny feathers may help advertise territory and maintain contact between nesting pairs. Conversely, cranes that nest in smaller wetlands at lower latitudes are generally dull gray or brown--colors that help shield them from predators of adjacent forests. Some cranes even "paint" their feathers with the iron oxides of mud to help them hide while nesting.

Habitat and social life

Swamps, marshes, reed beds, salt flats, river valleys, wet prairies, and lake shores all offer nesting and feeding habitat for most cranes. During migration and on their wintering grounds, some may also feed in farm fields and prairies. Two exceptions are the demoiselle crane, which occupies the steppes and deserts of eastern Europe, Central Asia, and northeast Africa; and the blue crane (A. paradisea), a bird of upland veld and savanna in southern Africa.

For much of the year, cranes have a rich and varied social life. They flock, feed, and roost together, busily communicating with one another vocally and by complex body language. Early on, they establish the flock's social order through ritual displays of preening, feather ruffling, and bowing stiffly to one another, to sort out the dominant one from the subordinates.

The flock stays together by low contact calls throughout the day, while screamlike sounds help the birds find one another when they're scattered. …