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| Grus americana |
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Identification:
With the exception of black wing tips (primary feathers) and a black mustache, the body plumage is snow white. Red skin and sparse, black hair-like feathers cover the birds crown. Eye color is golden yellow while the bill is yellowish and sometimes tipped with dull green. Visible portions of the legs and toes are black. Juveniles have entirely feathered heads. Juvenile plumage, except for primaries, is whitish and heavily mottled with cinnamon feathers that diminish as the chick ages. The primaries are dullish black. Whooping Crane chicks are one of two species born with blue eyes that later turn yellowish. Download FREE Whooping Crane images.
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Range:
Fossilized remains of the Whooping Crane date back several million years. Evidence from the Pleistocene Epoch shows that Whooping Cranes were once scattered throughout a much wider geographic range, extending from central Canada to Mexico and from Utah to the Atlantic coast. The species range shrank rapidly in the second half of the nineteenth century. Habitat loss and conversion due to westward expansion of settlers, unregulated hunting for sport and food, and the popularity of egg and specimen collecting at the turn of the century were the major factors leading to the species decline.
Except for a small non-migratory population living in southwestern Louisiana, breeding birds were extirpated from the U.S. portion of its historic breeding range by the 1890s. Whooping Cranes in Louisiana last nested in 1939 and disappeared by 1950. The only remaining natural, self-sustaining flock of Whooping Cranes breeds in Wood Buffalo National Park in the Northwest Territories, Canada and winters in Aransas National Wildlife Refuge (Texas). This flock reached a low of only sixteen birds in the winter of 1941-1942, and numbered under 35 birds over the next two decades. In 2006, there were over 200 birds in the flock. The population migrates during both spring and fall through a relatively narrow (80-300 km wide) corridor between Aransas and Wood Buffalo.
In 1975, experimental efforts to establish a second migratory wild flock began at Gray's Lake National Wildlife Refuge in southeastern Idaho. Eggs were transferred from the nests of Whooping Cranes at Wood Buffalo to nests of Greater Sandhill Cranes in Idaho. The Sandhill Crane "foster parents" raised the Whooping Cranes and taught them a traditional migration route of Sandhill Cranes to wintering grounds at Bosque del Apache National Wildlife Refuge in New Mexico. These cross-fostered Whooping Cranes, however, failed to form pair bonds with each other and suffered high mortality rates. The program was discontinued in 1989 and no Whooping Cranes survive in this population.
In the 1980's other options for establishing additional flocks were explored by the U.S. and Canadian Whooping Crane Recovery Team. The joint team decided that it was still critical to establish a second flock of Whooping Cranes in case disaster struck the natural flock. In 1993, thirty-three captive reared cranes were released at the Kissimmee Prairie of central Florida in an effort to establish a non-migratory population such as existed once in Louisiana. After multiple releases, this flock numbered 54 in 2006 and now has 17 nesting pairs. In 2006, four chicks fledged in this population.
In 1999, governmental, non-profit, and private organizations united to form the Whooping Crane Eastern Partnership (WCEP) to establish a new, migratory flock of Whooping Cranes to the core part of their historic breeding range. This flock migrates between Wisconsin and coastal Florida. To re-establish a migration route that was completely lost, the chicks are conditioned to follow an ultralight aircraft at the Necedah National Wildlife Refuge in central Wisconsin. The aircraft guides them on their first migration south. In the fall, the young Whooping Cranes and a team of pilots and biologists begin the 1200 mile journey to Chassahowitzka National Wildlife Refuge in Florida. The birds spend the winter in Florida and return unassisted to Wisconsin in the spring. In 2006, this flock numbered over 60 birds. Click on the link below to view a table of historic Whooping Crane numbers.
 Historic Whooping Crane Numbers.pdf
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Habitat & Ecology:
The Whooping Crane is native to a diverse array of ecosystems. Until its well-documented decline, it nested predominantly in the northern tallgrass prairie of the upper Midwest and the eastern aspen parklands of Canada. It also nested in such disparate regions as the taiga and sub-Arctic regions of the Northwest Territories, where the last remaining population has persisted to present times, and in the coastal marshes of Louisiana, where a non-migratory population existed. Wetland ecosystems historically used by wintering whooping cranes were diverse as well, ranging from the high plateau wetlands of central Mexico to the varied coastal wetlands that extended from Texas to South Carolina. Moreover, migratory populations of Whooping Cranes followed a variety of flyways between breeding and wintering areas. Although Whooping Cranes used, and continue to use, a wide range of environs they primarily depend on highly productive wetland ecosystems for nesting, over-wintering, and migratory stopover.
Mated pairs of cranes, including Whooping Cranes, engage in unison calling, which is a complex and extended series of calls coordinated between members of the pair. The unison call is a very distinct "whooping" sound that gave this species its common name. While calling, cranes stand in an upright posture, usually with their heads thrown back and beaks skyward during the display. In Whooping Cranes the female initiates the display and utters two, higher-pitched calls for every lower, male call. The male lifts his wings over his back during the unison call while the female keeps her wings folded at her sides. All cranes engage in dancing, which includes various behaviors such as bowing, jumping, running, stick or grass tossing, and wing flapping. Though it is commonly associated with courtship, dancing can occur at any age and season. Dancing is generally believed to be a normal part of motor development for cranes and thwarts aggression, relieves tension, and strengthens the pair bond.
The Whooping Crane's nests are constructed of bulrush and other wetland vegetation in shallow water. Females usually lay two eggs and incubation (by both sexes) lasts 29-30 days. The male takes the primary role in defending the nest against possible danger. Chicks fledge (first flight) at 80-90 days.
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Vocalizations:
Loud, rattling kar-r-r-o-o-o. With multiple variations.
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Diet:
All cranes are omnivorous. Principal foods of the Whooping Crane on their breeding grounds are mollusks and crustaceans, insects, minnows, frogs, and snakes. As Whooping Cranes were extirpated from their core breeding range in the Midwest before much scientific study had been done, we know little about what foods breeding birds in this area may have depended on. In coastal Texas the birds use the brackish bays, estuarine marshes, and tidal flats of the Gulf of Mexico. The cranes feed primarily on blue crabs, clams, fiddler crabs, shrimp, and other aquatic invertebrates, small vertebrates and plants. In upland areas Whooping Cranes forage for acorns, snails, insects, and rodents. |
Threats:
Habitat loss and alteration is one of the greatest threats at Aransas National Wildlife Refuge. The construction, maintenance, and use of the Gulf Intracoastal Waterway erodes wetland zones within the wildlife refuge where the Whooping Cranes winter. Pollution is another threat to wintering cranes at Aransas National Wildlife Refuge. Barge traffic through the Intracoastal Waterway carries contaminants and petrochemical products that, if spilled, could have catastrophic effects on the cranes, their habitat, and food supply. Oil extraction and the potential loss of freshwater inflow are additional significant threats to the health and productivity of the bay systems near Aransas. Habitat alteration through water diversions is a major threat along the Platte River and other migration stopovers. |
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ICF in Action:
Since 1976, ICF has participated in the captive propagation program for Whooping Cranes in collaboration with the U.S. Fish and Wildlife Service. In 1989, ICF became the second captive breeding center for the species with the arrival of 22 birds from the Patuxent Wildlife Research Center in Maryland. Studbooks (genetic record books) for both captive and wild populations of Whooping Cranes were established and are maintained by ICF. From the early 1990s – 2004, ICF contributed juvenile birds to the Florida experimental non-migratory flock. ICF also sponsors research and focuses on the Whooping Crane in many of its educational activities and outreach efforts. ICF has also participated in scientific evaluations of threats facing Whooping Cranes and other endangered species.
The eastern migratory Whooping Crane reintroduction project is being undertaken by the Whooping Crane Eastern Partnership (WCEP), a team of non-profit and governmental organizations whose founding members include the International Crane Foundation (ICF), International Whooping Crane Recovery Team, National Fish and Wildlife Foundation, Natural Resources Foundation of Wisconsin, Operation Migration Inc., US Fish and Wildlife Service (USFWS), US Geological Survey's Patuxent Wildlife Research Center, the National Wildlife Health Center, and the Wisconsin Department of Natural Resources (DNR). Many other dedicated partners are also involved.
Each of the partners is responsible for certain parts of the project. Operation Migration Inc., leads the training of the chicks behind ultralights and the ultralight migration south. Once the birds arrive in Florida, biologists from ICF and the USFWS care for the birds through their first winter. In the spring, ICF and USFWS personnel track the birds north, through the summer and in subsequent migrations – with help from the Wisconsin DNR and other collaborators. Aside from gathering valuable information that can help improve future releases, we occasionally intervene when a bird is lost or in trouble.
ICF sends several eggs to the Patuxent Wildlife Research Center in Laurel, Maryland each year to be part of the new group of chicks that will be prepared for release during the summer months. ICF's Veterinary Department provides service and care when the birds are in Wisconsin and, along with the Wisconsin DNR, performs a thorough health exam before the chicks' first fall migration.
ICF is working closely with US Fish and Wildlife Service personnel to develop a second technique for releasing Whooping Cranes into the wild. This technique, known as Direct Autumn Release, exposes the young cranes either one at a time or in small groups to older, experienced, wild Whooping Cranes or Sandhill Cranes. The young birds learn good foraging, loafing and roosting locations as well as the migration route from these older, wild birds.
In addition, a staff member of ICF's Conservation Education Department accompanies a portion of the ultralight-guided migration, providing educational outreach programs to schools, birding clubs, and other organizations along the cranes' migration route. These outreach programs are provided year-round to educate people about this exciting project and are linked with ICF's Three White Cranes, Two Flyways, One World education project. This project was initiated in 2006 to connect ICF's education programs in the eastern United States with conservation and education programs focusing on Siberian and Red-crowned Cranes in East Asia. Through annual field trips to ICF, classroom visits by ICF educators, and educator exchanges in the United States, China and Russia, students along both flyways are learning about cranes and their shared responsibility in protecting our global environment. Students are further connected through a project art exchange and the Three White Cranes, Two Flyways, One World website, which includes information on the cranes and people along the two flyways and an online classroom with student activities focusing on cranes and migration.
More than 60 percent of the project's estimated $1.8 million annual budget comes from private sources in the form of grants, public donations and corporate sponsors. Each partner is responsible for raising the funds needed to accomplish its part of the project. ICF is always working ahead to secure support for continuing phases of the project, as our involvement with the birds goes through all twelve months of each year. The partnership will be carefully planning next year's releases, and coordinating these plans with fund raising so that we can continue this landmark reintroduction project. If you would like to make a donation to this important conservation initiative, click here.
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Species accounts derived from:
Johnsgard PA. 1983. Cranes of the world. Bloomington: Indiana University Press.
Meine CD, Archibald GW. 1996. The cranes: status survey and conservation action plan. Gland, Switzerland: IUCN. |
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Fun Fact
The Whooping Crane is the tallest flying North American bird.
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