Sandhill Crane
Grus canadensis

Taxonomy and Distinguishing Characteristics
The Sandhill Crane, Grus canadensis, belongs to the order Gruiformes, along with other species of cranes, as well as rails, coots, limpkins and buzzards. It is in the Gruidae family, which includes 15 species of cranes. With fossils dating back to about 10 million years ago, cranes are among the oldest living birds. Sandhill Cranes are known for their loud, bugling calls and elaborate courtship dances. They are long-legged, long-necked birds that stand about 1.2 meters tall and have a 2-meter wingspan. The sexes are similar in appearance, but males are usually larger than females. They have long ornamental feathers on their wings that droop over the short tail feathers. They have white cheeks contrasting with a gray neck and body, and have a bare patch of red skin that extends from the base of the bill above the eyes to the back of the head. There are six subspecies of Sandhill Cranes, three that are migratory and three that are non-migratory. The three migratory subspecies include the Greater Sandhill (Grus canadensis tabida), which is the largest of the subspecies, the Lesser Sandhill (Grus canadensis canadensis), which is the smallest Sandhill, and the Canadian Sandhill (Grus canadensis rowani), which is intermediate in size. The three non-migratory subspecies include the Florida Sandhill (Grus canadensis pratensis), the Mississippi Sandhill (Grus canadensis pulla), and the Cuban Sandhill (Grus canadensis nesiotes).

Distribution
The breeding range and wintering range of Sandhill Cranes can be seen in the range map to the left. The Florida Sandhills are found throughout the year in Florida and Georgia. The Mississippi Sandhills are found year-round in southwestern Mississippi, and the Cuban Sandhills are found year-round in western Cuba. The ranges of the migratory subspecies overlap in many areas. The Greater Sandhills have a wide breeding range extending from northern Illinois north to Vancouver Island in Canada, and spend the winter in Florida, New Mexico, Nevada and California. The Canadian Sandhills breed in central Canada and winter along the Gulf Coast of Texas. The Lesser Sandhills nest in Alaska and the eastern coast of Siberia, and winter along the Gulf Coast of Texas, New Mexico, California's Central Valley and in north central Mexico.

Migration
The different populations of Sandhill Cranes utilize different migratory routes depending on where they breed and winter. The mid-continent population of Sandhills, which includes birds that winter in Texas, New Mexico, Arizona, and Mexico, has a major staging area in the Platte River Valley in central Nebraska. Nearly 500,000 Sandhills (mainly Canadian and Lesser Sandhills), representing 80% of the world's population of Sandhill Cranes, stop to feed in the fields along the Platte River for up to six weeks in the spring. The timing of migration varies by population, but the mid-continent population leaves the wintering areas in Texas in late February to early March and arrives at staging areas in mid- to late March. The birds leave the staging areas in Nebraska in early to mid-April, and arrive at nesting areas in late April to mid-May. Fall migration from the breeding areas in Siberia, northern Canada and Alaska begins in late August, and the birds arrive at the wintering grounds between October and January. During migration, the birds make use of thermals to soar, but also power fly by flapping their large, powerful wings.

Habitat
During all stages of their annual cycle, Sandhill Cranes tend to inhabit open grasslands and freshwater marshes, though the particular habitat type varies by region. The Cuban Sandhills are adapted to living in drier habitats than the other subspecies. The mid-continent population breeds in wet marsh or sedge meadow areas of tundra. At the staging areas in the Platte River, the birds feed in corn fields and wet meadows surrounding the river, and roost in shallow sandbars in the open channels of the river. On the wintering grounds, they forage in wetlands, coastal prairie, or fields of sorghum or corn stubble, and roost in lakes, shallow rivers or open water marshes.

Food
Sandhill Cranes are omnivorous. They use their bills to probe beneath the ground for food items, in addition to gleaning seeds and other food items aboveground. Their diets vary widely depending on what is available in various seasons and locations. They feed on tubers, berries, the seeds of various plants, cultivated grains, insects, snails, reptiles, amphibians, small mammals, and nestling birds.

Courtship Behavior and Breeding
Sandhill Cranes are monogamous, and mated pairs tend to return to the same nesting area year after year.Sandhill Cranes are known for their elaborate courtship dances, which consist of eight different displays accompanied by loud bugling calls made by the pair in unison. The dances are important for mate selection, maintaining the bond between a mated pair, and allowing a mated pair to be synchronized reproductively (meaning the male and female are ready to reproduce at the same time). In the mid-continent population, courtship begins at the staging area in the Platte River Valley, and is triggered by changes in day length that cause hormonal changes in the birds. Sandhill Cranes usually do not breed before they are 3 years old, and most do not successfully breed before 8 years old. The nest site is usually in a marsh or in some body of standing water with emergent vegetation. The pair gathers nesting material from the surrounding vegetation and the female usually builds the nest. The clutch size is 1 to 3 eggs. The male and female take turns incubating during the day, and the female incubates at night. Incubation lasts about 30 days. The precocial young are able to leave the nest within 24 hours. The adults feed the young for the first 10 days after hatching, and then the young begin to feed on their own. The young are able to fly at about 2 months old, but remain with their parents until they are 9-10 months of age. They migrate along with their parents and rely on them for protection and to help them find food. Usually only one young per brood survives to the fledgling stage.

Conservation Status
The major threat to Sandhill Crane populations is habitat destruction. Hunting may also pose a threat to some populations. The Cuban and Mississippi Sandhills are both listed as endangered species, and the reintroduction of captive-bred Mississippi Sandhills has been necessary to prevent the extinction of this population. Wetland conservation in the wintering, breeding, and staging areas used by the different Sandhill Crane populations are necessary to maintain their populations. Since a mated pair of cranes only produces a maximum of one young crane per year, and young cranes don't begin reproducing until about 5-8 years of age, their population growth rates are very slow. Thus, they would not be able to recover from a sudden decline in their populations, making it extremely important to carefully monitor their populations and conserve the habitats on which they depend.

References and Further Reading
Tacha, T.C., S.A. Nesbitt, and P.A. Vohs. 1992. Sandhill Cranes (Grus canadensis). In The Birds of North America, No. 31. (A. Poole and F. Gill, editors). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D.C.
Nebraska Game and Parks Commission web site: http://www.ngpc.state.ne.us/wildlife/cranes.html