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Whooping Crane
Grus americana
The story of the Whooping Crane is one of the best-known examples of conservation in action. Through decades of research, experimentation, and the dedication of many, the Whooping Crane has been brought back from the edge of extinction.
The Whooping Crane is unmistakable. Standing at almost 5 feet, it is the tallest North American bird. Regal in appearance, it is almost entirely white, with black legs and black wingtips. The head is particularly handsome, with a crown of red and black, yellow eyes, and a red "mustachial" stripe behind the long, yellow-based, dark-tipped bill. The black wingtips are mainly visible in flight, when the bird's nearly eight-foot wings are fully outstretched. Young birds are brown, changing to white late in their first year. The Sandhill Crane, North America's only other resident crane species, is substantially smaller and almost entirely gray in color. In flight, both crane species fly with their long necks outstretched, as opposed to egrets and herons that generally fly with their necks drawn in.
Although thought to have never been very numerous, these birds once ranged throughout the plains and prairies of central North America, wintering on the Gulf Coast, parts of the Atlantic coast, and as far south as northern Mexico. They are now absent from much of their historic range. The largest (and only remaining wild) flock of Whooping Cranes spends the summer in Wood Buffalo National Park, on the border between Alberta and the Northwest Territories, and winters in the marshlands of the Aransas National Wildlife Refuge on the Gulf Coast of Texas. Conservation efforts undertaken over the last few decades have aimed to reintroduce the species to a number of areas. As a result of these efforts, an introduced population now migrates between Wisconsin's Necedah National Wildlife Refuge and the Chassahowitzka National Wildlife Refuge on Florida's Gulf Coast. Yet another population, this one non-migratory, has been introduced to the Kissimmee Prairie in central Florida. Experimental flocks have been released in other areas of the country in recent decades, but these releases have not proven successful.
Whooping Cranes rely on marshy wetland habitats at all times of year, whether on the breeding grounds, at migratory stopovers, or on the wintering grounds. Agricultural areas and drier, upland habitats surrounding wetlands are also used for feeding.
Omnivorous creatures, Whooping Cranes make use of a wide variety of foods found in wetlands or on adjacent upland habitats. Whooping Cranes are known to eat crabs, frogs, snakes, mollusks and fish, as well as mice, insects, plant tubers, nuts, berries and agricultural grains. A wide range of feeding methods are employed, from probing in water or mud, to digging up tubers, plucking berries or nuts from shrubs, gleaning waste grains from fields, or grabbing prey directly from the ground or water.
Relatively long-lived, the Whooping Crane pairs with one partner for life. Partnerships often begin to form when the birds are as young as two, but breeding doesn't take place until the third or, more likely, fourth year. As pair bonds solidify, the birds interact with one another in a variety of ways, the most spectacular of which is a type of "Crane Dance." In the dance ritual, one bird will engage the other through a series of movements such as bowing, flapping and leaping. If successfully enticed, the other member of the pair will join in, and soon both birds run about together, performing a complicated series of motions – leaping and bowing, stretching and flapping, and bouncing into the air in unison. This majestic display is a good indication that strong pair bonds have been formed.
Paired cranes establish a territory, which will be used year after year. The male defends the territory, and the female sets about building the nest. Nests are often located in shallow water, where the female gathers nesting materials into a small pile with a slight depression at the top. Only two eggs are laid per clutch. Eggs are about four inches in length, and white, creamy, or buff in color, with light brownish blotches at one end. Both members of the pair incubate the eggs for about 35 days. Whooping Crane chicks are well developed upon hatching, capable of moving about and swimming almost immediately. Parents and young stay close to the nest for the first several days, but soon begin to wander further afield until the young are capable of flight at about three months old. Cranes remain together in family groups throughout the winter, and often right through to the following summer, but young birds eventually move off to associate with other birds of similar age.
Unlike most other birds, young Whooping Cranes must be taught how to migrate. Historically, migratory and non-migratory populations of these birds existed, and the same is true today. The Wood Buffalo – Aransas population migrates approximately 2500 miles each way along North America's Midwest flyway, with adult cranes leading the young. The Wisconsin – Florida population is also migratory, but in this case, the majority of young cranes make their first flights behind a human and the famous Operation Migration ultralight aircraft. The first such flight took place in the fall of 2001, when scientists led a group of captive-bred juvenile birds to Florida. In the spring of 2002, these birds returned to Wisconsin on their own, in yet another remarkable success story for the species. The only current non-migratory population is the introduced flock of central Florida.
BirdLife International (2006) Species factsheet: Grus americana, Whooping Crane
Lewis, James C. 1995. Whooping Crane (Grus americana). In The Birds of North America, No. 153 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D. C.
Whooping Crane Conservation Association. http://www.whoopingcrane.com/. Website accessed August 2007.
~593
~593
Endangered
Thanks to great efforts across many fronts, the Whooping Crane population continues to grow. The main migratory population numbered 237 birds at Aransas in late 2006. In summer 2007, this population produced a record-breaking 84 chicks from 65 nests in Canada's Wood Buffalo National Park. Elsewhere, captive-raised chicks continue to be introduced within the migratory Wisconsin-Florida flock. In 2006, a juvenile from Wisconsin became the first wild-reared Whooping Crane to make the Wisconsin to Florida migration in over a century. Central Florida's non-migratory population has enjoyed only limited breeding success since 2000 – one chick fledged in the wild there in 2007. There are five captive Whooping Crane breeding facilities in the United States (Patuxent Wildlife Research Center, International Crane Foundation, Calgary Zoo, San Antonio Zoo, and Species Survival Center in New Orleans), all of which either provided eggs or produced young in 2007. This species is slowly crawling back from the brink, but numbers remain far shy of the estimated 1,400 birds that existed back in 1860.
The decline of the Whooping Crane was the result of a number of factors. Because loss of wetland habitat was a primary cause, breeding and wintering sites are currently protected, but vital migratory staging areas require management and protection as well. In the Aransas National Wildlife Refuge, heavy boat traffic and mineral exploration have both contributed to the loss of wetlands, though these threats have been reduced recently and even reversed in some cases.
Hunting contributed to the decline of cranes in decades past, and was largely responsible for the species' complete extirpation from Florida by the 1920s. Today, this endangered species enjoys full protection from harvest, yet accidental shooting by careless individuals has still claimed a few birds in recent years. In addition, the birds are at risk of collisions with man-made objects, such as electrical power lines.
Whooping Cranes reproduce at a slow rate (generally no more than one chick per season). Additionally, most remaining wild breeders are found in Wood Buffalo National Park, which is at the far northern edge of the species' historical range. At that latitude, the breeding season is relatively short, reducing the chances of second nesting attempts should a nest fail. These factors hamper efforts to increase the species' numbers. They also mean that each individual is important to the survival of the species and any loss is a major setback.
In 1937, only two wild flocks of Whooping Cranes, totaling fewer than 40 birds, existed in the world. In that year, the U.S. government created the Aransas National Wildlife Refuge to protect the migratory flock, but the Canadian breeding grounds for this species had yet to be discovered. In the 1940's the U.S. Fish and Wildlife Service and the National Audubon Society established the Cooperative Whooping Crane Project, which successfully sought to learn more about the biology of this species and to develop future management strategies. In 1967, this species was granted protection under legislation that preceded the Endangered Species Act that protects the species today.
The techniques developed to restore wild populations of Whooping Cranes have been groundbreaking. Captive breeding programs have been rigorously designed to maintain genetic diversity as they increase wild populations of birds. Experimental flocks have been established to test ways of reintroducing birds so that they will be able to survive on their own and avoid humans. The well-publicized Operation Migration uses ultralight aircraft to guide juvenile birds from Wisc. to Fla. with remarkable success.
Currently, the main threats to the Whooping Crane are its limited range and extremely small population size. Any disaster at the breeding or wintering sites (such as disease, a hurricane or an oil spill) could have a huge negative impact upon the total population of these elegant birds. This vulnerability, which is a risk to many endangered species, was tragically illustrated in early 2007. On February 2, violent storms swept through central Florida, killing 17 of 18 young Whooping Cranes that had only recently migrated to the wintering grounds along Florida's Gulf Coast and were all being kept each night in a single cage. Although free-flying, birds wintering in Aransas face the constant possibility of a similar event each season. The establishment of wild flocks at several locations around North America remains an important conservation goal for Whooping Crane researchers. By increasing the range of the species, the threat from any single catastrophic event is reduced.
The Whooping Crane has survived into the 21st century thanks to the extensive and imaginative conservation efforts employed by researchers from the U.S. Fish and Wildlife Service, the Canadian Wildlife Service and a variety of other institutions and non-profit groups.
One example of the value of wetland habitat is Audubon's Rowe Sanctuary in Nebraska. You can visit the site during migration, to view the world's largest concentration of Sandhill Cranes (and an occasional Whooping Crane) from observation blinds on the banks of the Platte River. Trips are conducted every year during March and early April, when over 500,000 Sandhill Cranes, along with hundreds of thousands of ducks and geese, converge on the Platte. To learn more about how this sanctuary is managed to suit the needs of its avian visitors, visit the Rowe Sanctuary's website.
The Whooping Crane would probably not be with us if not for the establishment of key wildlife reserves in Canada and the U.S. Unfortunately, the National Wildlife Refuge System in the U.S. is often overlooked during the government's budgetary process. Increases in funding for fiscal year 2008 will restore some direly needed funds, but may not be sufficient to revitalize the system following years of neglect. To learn more about how you can help gain funding for our National Wildlife Refuges, read Audubon's Refuges in Crisis report.
Find out about actions you can take including Audubon programs and activities.
To learn more about Whooping Crane programs in Florida, or to report a Whooping Crane sighting in that state, visit the webpage of the Fish and Wildlife Research Institute
To learn more about Whooping Cranes and read the latest news, visit the website of the
Whooping Crane Conservation Association
Read more about Operation Migration and how you can contribute.
Read more about the efforts of Audubon's Important Bird Areas program in Texas.
Learn more about this species and other birds through these resources.
BirdLife International (2006) Species factsheet: Grus americana, Whooping Crane
Lewis, James C. 1995. Whooping Crane (Grus americana). In The Birds of North America, No. 153 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D. C.
Whooping Crane Conservation Association. http://www.whoopingcrane.com/. Website accessed August 2007.
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