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Whooping Crane
Grus americana
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Threats
habitat loss through land conversion,
dredging, dam
construction
STATUS:
ESA -- ENDANGERED
IUCN -- ENDANGERED
SIZE:
Weight
15Ð16 pounds (6.8Ð7.3 kg)
Height:
Up to 60 inches (150 cm)
Wingspan:
7.5 feet (2.3 m)
HABITAT:
Shallow wetlands,
coastal estuaries,
and wet grasslands
POPULATION:
250Ð300
(90 in captivity)
CURRENT RANGE:
Northern Alberta and Northwest Territories in Canada to Gulf of Mexico
CONSERVATION:
reintroduction efforts;
captive-breeding programs;
wildlife refuges; CITES
trade restrictions
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Elegant Bird . . . Shy Habits
Every winter a flock of large, graceful birds trumpets its arrival at the Aransas National Wildlife Refuge on the Gulf Coast of Texas. They are migrating whooping cranes, completing their annual journey from Canada. There are about 140 birds in the flock, and they are the last of their kind in the wild.
Whoopers are wetland birds, nesting and feeding in shallow lakes and wide, open waterways. They feed on freshwater crustaceans, fish, berries, frogs, rodents, insects, and small birds. Their name comes from their call -- a haunting, bugle-like trumpeting. Despite their impressive vocalizations, whoopers are shy and secretive and easily disturbed. If a pair of whoopers finds nesting conditions unsuitable -- and they sometimes do, for reasons that may not be discernible to us -- they will not reproduce. When they do nest, the female lays two eggs, only one of which normally hatches.
The courtship dance of
whooping cranes is one
of the greatest shows in nature. Wing flapping, head bowing, strutting, and great leaps into the air are accompanied by loud whoops and bugles. They also act this way when theyÕre defending their territory.
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Whooping cranes mature slowly, as birds go. They don't breed until they're about four years old
and normally raise only one chick at a time. Because of their slow reproductive rate, whooper populations cannot easily rebound from natural or man-made disasters.
Whooping cranes have never been very numerous. It's estimated that no more than 1,400 whooping cranes
inhabited North America in 1870.
Whooping cranes, like most other cranes, mate for life. In Japan, traditional wedding kimonos always have a crane embroidered on them. They are symbols of both longevity and marital harmony.
A single pair of whooping cranes requires 300Ð400 acres to find adequate food and nesting sites.
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There Goes the Neighborhood . . .
Over the past two centuries, vast areas of wetlands in North America have been ploughed up for farmland, paved over for the construction of roads and buildings, and transformed by dams into water-supply systems. Whooping cranes were among the first species to show the effects of this transformation. They have hovered near extinction for most of this century. Efforts to save the whooping crane began as early as 1918. By 1941, there were just 22 whooping cranes left -- six nonmigratory, captive-reared birds in Louisiana, and 16 in the flock that came each year to
Aransas. This tiny population hung on, and in 1967 an aggressive intervention program was launched to save the species.
The Winding
Road to Recovery
As a first effort, wildlife experts took advantage of the whooping cranes' two-egg, one-hatchling habit. They took the "extra" eggs from whoopers' nests and placed them in the nests of sandhill cranes, close relatives of the whooping cranes. The program appeared to work: the foster chicks were accepted and raised by sandhill hens. Unfortunately, these foster whoopers learned to be sandhill cranes, not whooping cranes. As adults they wouldn't breed with their own kind.
Ultimately, though, successful captive breeding programs were established in Maryland, Wisconsin, and Alberta, Canada. In 1993, a nonmigratory flock of whoopers was released in Florida. We should know very soon if this program is successful.
The whooping crane was one of the first birds listed as an endangered species under the ESA of 1973. Recovery programs run by the U.S. Fish and Wildlife Service, the Florida Game and Freshwater Fish Commission, the Canadian Wildlife Service, and the International Crane Foundation have all contributed to the whooping crane's survival. According to a 1994 census, about 300 whoopers are alive, 90 of which are held in captivity.
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