hello, heres some info ive found for you
SANDHILL CRANES
Height: ~80 cm-1.2 m, 3-5 ft
Weight: ~ 3-6.5 kg, 6.5-14 lbs
Wingspan: ~5-6 ft.
Population: ~650,000
Trend: Stable to increasing, except for isolated populations (see below),
Subspecies: Grus canadensis canadensis (Lesser Sandhill)
Grus canadensis tabida (Greater Sandhill)
Grus canadensis rowani (Canadian Sandhill)
Grus canadensis pratensis (Florida Sandhill)
Grus canadensis pulla (Mississippi Sandhill)
Grus canadensis nesiotes (Cuban Sandhill)
The different sub-species of Sandhill Crane vary greatly in size and weight. Lesser Sandhills, who breed at more northern latitudes such as the arctic, are the smallest, weighing on average about 6-7 pounds and standing 3-3.5 feet tall. At the other end of the extreme, temperate-nesting Greater Sandhills are the largest sub-species and average 4.5-5 feet tall and 10-14 pounds. Body plumage is characterized by varying shades of gray. In many areas, wild Sandhills preen iron-rich mud into their feathers creating a deep rusty brown hue which lasts during spring and summer. As fall advances, these rusty feathers molt and the birds return to their grayish appearance. In some regions, however, iron-rich mud is absent and the birds appear grey all year. The forehead and crown are covered with reddish skin. Face, chin, upper throat, and nape are white to pale gray. Adults have a white cheek patch. Legs and toes are black. In general, males and females are virtually indistinguishable but within a breeding pair, males tend to be larger than females.
Juvenile plumage changes from cinnamon brown to gray as the bird matures during the first year.
Range:
Sandhill Cranes are the most abundant of the world’s cranes. They are widely (though intermittently) distributed throughout North America, extending into Cuba and far northeastern Siberia. The three migratory subspecies (Lesser, Greater and Canadian) are distributed across a broad breeding range in the northern U.S. and Canada as well as eastern Siberia, with wintering grounds in the southern United States and northern Mexico. The three non-migratory subspecies (Mississippi, Cuban, and Florida) have restricted ranges in the southern United States and Cuba.
Habitat & Ecology:
Sandhill Cranes are primarily birds of open fresh water wetlands, but the different subspecies utilize habitats that range from bogs, sedge meadows, and fens to open grasslands, pine savannas, and cultivated lands. Sandhill Cranes occur at their highest breeding density in habitats that contain open sedge meadows in wetlands that are adjacent to short vegetation in uplands.
Mated pairs of cranes, including Sandhill Cranes, engage in unison calling, which is a complex and extended series of coordinated calls. While calling, cranes stand in an upright posture, usually with their heads thrown back and beaks skyward during the display. In Sandhill Cranes the female initiates the display and utters two, higher-pitched calls for each male call. While calling, the female raises her beak about 45 degrees above the horizontal while the male raises his bill to a vertical position. All cranes engage in dancing, which includes various behaviors such as bowing, jumping, running, stick or grass tossing, as well as 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.
Nests of all Sandhill Cranes are usually low mounds built out of dominant vegetation in the nesting area. Typically nests are located in wetlands, but Sandhill Cranes will sometimes nest in uplands, especially in Cuba. Females usually lay two eggs and incubation (by both sexes) lasts 29-32 days. The male takes the primary role in defending the nest against possible danger. Chicks fledge (first flight) at 67-75 days.
Vocalizations:
Loud, rattling kar-r-r-o-o-o. With multiple variations.
Contact Call
Contact calls are low pitched and soft calls that allow the birds to keep in contact with each other even if they can’t see each other in the deep grass or reeds. (Note: This is a soft call; you may need to turn up your computer speaker system.)
Unison Calls
UnisonCall are produced by a pair of birds. This call, performed with the birds standing close to each other and in a synchronized duet, is a way of reinforcing the pair bond between a female and a male bird. It may also be used by a pair to threaten predators or other cranes.
Guard Call
Guard Calls are single loud vocalizations used to warn other cranes of danger or to threaten other cranes. These calls are sometimes echoed by the other member of the pair. You can hear this "echoing" in this sample audio clip
Diet:
All cranes are omnivorous. Sandhill Cranes are generalists and feed on a wide variety of plant tubers, grains, small vertebrates (e.g. mice and snakes), and invertebrates such as insects or worms. Sandhills find these foods in uplands and in shallow wetlands. Like most cranes, flightless chicks forage primarily on a diet of insects and other protein filled foods during their early stages of rapid growth. The Sandhill’s tendency to feed on plant tubers creates conflicts with farming. Sandhill Cranes are adept at probing in the ground and finding planted agricultural seeds such as corn. When large flocks of cranes feed on planted fields, the damage they cause to an unprotected crop can be severe enough to force the farmer to replant the entire field.
Threats:
Loss and degradation of riverine and wetland ecosystems are the most important threats to Sandhill Crane populations. For the migratory populations, this is of greatest concern in staging and wintering areas. Spring staging areas along the Platte River in Nebraska are of special concern because of their importance to the migratory subspecies and the development pressures facing this region. Approximately 80% of all Sandhill Cranes utilize a 75-mile stretch of the Platte River in spring migration. Elsewhere, small breeding populations can face disproportionate mortality on fall staging areas due to over-hunting. Residential and commercial development pressures facing lands occupied by birds belonging to non-migratory subspecies in Mississippi, Florida, and Cuba also pose significant threats.
ICF in Action:
Though Sandhill Crane populations in the northern boreal forest and arctic have likely been stable for a decade or more, Sandhill Crane populations in temperate regions of the U.S. and Canada have been expanding rapidly. This wildlife success story is possible because a recovering crane population has found available wetlands to nest in and agricultural lands that are suitable for foraging. The positive relationship between crane and farmer is precarious and currently is threatened by growing amounts of crop damage caused by cranes. To help re-establish a more positive relationship between cranes and the landowners who provide habitat, ICF is helping to develop a new technique to treat corn seeds with a deterrent before the seeds are planted. In response, foraging Sandhills avoid treated seed but remain in the field to feed non-destructively on other foods. ICF is currently collaborating with partners to make this technique available to farmers throughout the Midwest.
Of equal importance is our ability to monitor crane populations for new problems that may arise. To this end, ICF sponsors the Annual Midwest Crane Count through which thousands of volunteers count cranes each April. Measuring the increase or decrease of crane populations is a critical step in fine-tuning management plans for any species.
2007-02-09 02:56:59
·
answer #1
·
answered by Mystic Magic 5
·
1⤊
1⤋