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By Marie S. Harris
Geographic Range
In North America, this species breeds as far north as Alaska and the Arctic coast of Canada south into the Great Lakes region and westward across Idaho, Nevada and Oregon. It also breeds in the extreme southeastern United States and Cuba. The winter range of this species includes parts of California, New Mexico, Arizona, Texas, Georgia, Florida and northern Mexico. Populations of sandhill cranes are also found in northeastern Siberia, Andyrland, and on the Chyukotski peninsula and Wrangel Island. ()
Biogeographic Regions:
nearctic 
(native ); palearctic (introduced ); neotropical (native ).
Habitat
Most sandhill crane populations nest in open grasslands, such as wet meadows, and freshwater marshes or bogs. There are six subspecies of sandhill cranes, and each typically nests in the open, wet grassland habitats of their region. The Cuban population of sandhill cranes (Grus canadensis nesiotes) is an exception, inhabiting dry, isolated regions, sometimes in rocky and mountainous terrain.
Sandhill cranes prefer to be far from human habitation. However, during migration, they are commonly seen feeding on crops and crop residue in agricultural fields. At night they congregate to roost in large marshes. ()
These animals are found in the following types of habitat:
temperate ; tropical ; terrestrial .
Terrestrial Biomes:
savanna or grassland ; forest .
Other:
agricultural ; riparian .
Physical Description
(112.64 to 183.04 oz)
(6.56 ft)
Sandhill cranes are large birds with heavy bodies and long necks and legs. They stand about 1.2 m tall, with wing spans of about 2 m. They are uniformly grayish, with a white cheek and a bald red crown. Sandhill cranes can be distinguished from other large wading birds in flight by their outstretched neck, and their wingbeats, which are a slow downward beat followed by a quick upward flick.
Male and female sandhill cranes are similar in appearance, though males are usually larger than females. For example, males of the G. c. canadensis subspecies average 3.75 kg whereas females average 3.34 kg. Juvenile sandhill cranes tend to be much more brownish than adults.
There are six subspecies of sandhill cranes. These subspecies are distinguished based upon morphology (size) and geographic separation. ()
Some key physical features:
endothermic ; bilateral symmetry ; polymorphic .
Sexual dimorphism: male larger.
Reproduction
Sandhill cranes raise one brood per year.
In non-migratory populations, egg-laying can happen any time between December and August. In migratory populations, sandhill cranes usually lay their eggs in April and May.
Sandhill cranes are perennially monogamous. Breeding pairs remain together from year to year, maintaining the pair bond by performing courtship displays, remaining in close proximity and calling together in unison. Breeding pairs form during spring migration. This species is noted for its elaborate courtship displays. Five courtship displays have been identified as part of "dancing," the primary mechanism of pair formation in this species. These displays are the Upright wing stretch, Horizontal head pump, Bow, Vertical leap and Vertical toss. Three courtship displays are used exclusively by paired adults to maintain the pair bond and synchronize reproductive development. These are the Bill up, Copulation and Unison call displays. ()
Mating systems:
monogamous .
Sandhill cranes raise one brood per year. In non-migratory populations, egg-laying can begin as early as December or as late as August. In migratory populations, egg-laying usually begins between early April and late May. Both members of a breeding pair build the nest using plant material from the surrounding areas. Nest sites are usually in marshes, bogs, or swales, though cranes will occasionally nest on dry land.
The female lays 1 to 3 (usually 2) eggs that are oval-shaped and dull brown with reddish brown markings. Both parents participate in incubation, which lasts 29 to 32 (usually 30) days. Incubation begins with the laying of the first egg and continues until the second egg has hatched. The chicks are precocial; they hatch covered in down, with their eyes open and are able to leave the nest within 24 hours of hatching. The parents brood the chicks for up to 3 weeks after hatching. They feed the young intensively for the first few weeks, and with decreasing frequency until they reach independence at 9 or 10 months old.
The chicks remain with their parents until 1 or 2 months before the parents begin laying the next clutch of eggs. After leaving their parents, the chicks form nomadic flocks with other subadults and non-breeders. They remain with these flocks until they form breeding pairs and begin breeding between the ages of 2 and 7 years old. ()
Key reproductive features:
iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous .
Sandhill cranes provide extended biparental care to their young. Both members of a breeding pair build the nest, incubate the eggs and feed and protect the chicks for up to 10 months after hatching. ()
Parental investment:
precocial ; pre-fertilization (provisioning, protecting: female); pre-hatching/birth (protecting: male, female); pre-weaning/fledging (provisioning: male, female, protecting: male, female); pre-independence (provisioning: male, female, protecting: male, female); post-independence association with parents.
Lifespan/Longevity
Sandhill cranes that reach independence are expected to live about seven years. The oldest known sandhill crane lived at least 21.6 years.
Behavior
Sandhill cranes are diurnal and partially migratory. Northern populations move south during the winter months whereas southern populations remain near the breeding sites year round.
Cranes are usually found in pairs and family groups. During the migration and winter, family groups may join with non-mated cranes to form survival groups that feed and roost together. These survival groups often congregate at migratory staging areas and on the wintering grounds. ()
Home Range
Two studies resident sandhill crane populations in Florida estimated average home ranges of 657 and 1366 hectares.
Communication and Perception
Sandhill cranes communicate primarily using physical displays (see Mating Systems section) and vocalizations. Adult sandhill cranes have a repertoire of more than a dozen calls, which can be described as variations on "trills", "purrs" and "rattles". Calls are used in territorial advertisement, social interactions and to notify others of a nearby predator. Breeding pairs may call in duet in order to advertise their occupancy of a territory. ()
Food Habits
Sandhill cranes are omnivorous birds that use their bills to probe for subsurface food and glean seeds and other foods. These birds feed on land or in shallow marshes with vegetation. Foods vary depending on what is available. Cultivated grains such as corn, wheat and sorghum are a major food source in their diet when available. In northern latitudes, a wider variety of foods are consumed, including berries, small mammals, insects, snails, reptiles, and amphibians. ()
Primary Diet:
omnivore .
Animal Foods:
mammals; amphibians; reptiles; insects; mollusks.
Plant Foods:
seeds, grains, and nuts; fruit.
Predation
When approached by an avian predator, sandhill cranes fly at the predator, kicking it with their feet. When approached by a mammalian predator, sandhill cranes move toward the predator with their wings spread and their bill pointed at the predator. If the predator persists, sandhill cranes will attack, hissing, stabbing with their bills and kicking with their feet. ()
Ecosystem Roles
Young and sick sandhill cranes provide food for their predators. Sandhill cranes affect the populations of species that they prey upon. They also host at least 24 different species of parasites. ()
Economic Importance for Humans: Negative
Sandhill cranes feed on crops where they are available.
Ways that these animals might be a problem for humans:
crop pest.
Economic Importance for Humans: Positive
Sandhill cranes feed on insects and rodents that may damage crops. ()
Ways that people benefit from these animals:
controls pest population.
Conservation Status
IUCN Red List: [link]:
Least Concern.
US Migratory Bird Act: [link]:
Protected.
US Federal List: [link]:
Endangered; No special status.
CITES: [link]:
Appendix II.
State of Michigan List: [link]:
No special status.
Sandhill cranes are protected under the U.S. Migratory Bird Act and CITES Appendix II. Two subspecies of sandhill cranes, Grus canadensis nesiotes (Cuba sandhill crane) and Grus canadensis pulla (Mississippi sandhill crane), are federally endangered in the United States. Low reproduction rates limit population recovery in this species, especially by the mid-continent population, which is subject to hunting. Reintroduction of captive-reared birds has been instrumental in maintaining population size. Protection of wetland habitats is also essential for the survival of this species. ()
Contributors
Marie S. Harris (author), University of Michigan.
Kari Kirschbaum (author, editor), Animal Diversity Web Staff.
