![]() The chicks are called colts and are precocial they hatch covered in down, with their eyes open, and able to leave the nest within a day. Both parents incubate the eggs for about 30 days. Females lay one to three (usually two) oval brown eggs with reddish markings. ![]() Nest sites are usually in or within 300 yards of marshes or bogs, though occasionally (rarely) on dry land. Both members of a breeding pair build the nest using plant material from the surrounding area. In Michigan, nesting usually begins in April or May. Sandhill cranes raise one brood per year. Sandhill cranes will sometimes abandon nests if their mates die or because of human disturbance. During drought years, the risk of predation increases. Low water levels and flooding also account for nest failures. The parents will attempt to defend the nest, but eggs and nestlings can be lost to raccoons, coyotes, bobcats, foxes, ravens, crows, hawks, eagles and owls. Predation is a common reason for nest failure. Lots of factors determine nest success or failure for sandhill cranes. Waste corn is useful to cranes preparing for migration in the fall and for cranes raising young in the spring. They feed on berries, tubers (plants), small vertebrates (frogs, mice, etc), and invertebrates (crayfish, earthworms, snails, insects, etc). The oldest sandhill crane on record was at least 36 years, 7 months old.Īmong northern races of sandhill cranes, the diet is most varied, especially among breeding birds. Cranes are seen together as bonded pairs. Monogamous, cranes mate for life - which can mean two decades or more - and stay with their mates year-round. Populations studies - while notoriously inconsistent - also indicate the EP of sandhill cranes is stabilizing and leveling out, due to wetland habitats reaching self-regulating natural carrying capacities within prime breeding habitats. Michigan is at the northern most breeding range and our recruitment rate falls within the necessary percentage to simply maintain the current population status. The non-hunted Eastern Population of sandhill cranes has an average recruitment of 12 percent and scientific studies suggest that recruitment rates of 5 to 10 percent are necessary for population maintenance at current levels. Although some sandhill cranes are physically capable of breeding as early as two years of age, most sandhill cranes may reach the age of four to seven years of age before breeding. This slow rate of what biologists call “ recruitment ” has resulted in a very long and slow recovery from near extirpation in Michigan. Sandhill cranes are one of the slowest reproducing birds in North America. Sandhill cranes have been protected in the Great Lakes State since 1916 under the Migratory Bird Treaty Act (i.e., closure of hunting in 1918), which makes it unlawful to "take" (pursue, hunt, shoot, poison, wound, or kill) the sandhill crane within the state of Michigan. A 10-million-year-old crane fossil may be from a prehistoric relative or the direct ancestor of sandhill cranes. The oldest unequivocal sandhill crane fossil is 2.5 million years old, older by half than the earliest remains of most living species of birds. The fossil record shows sandhill cranes have one of the longest fossil histories of any extant bird. The large wingspan make cranes very skilled soaring birds, often using thermals to obtain lift and stay aloft for many hours, requiring only occasional flapping of their wings and consequently expending little energy. ![]() ![]() Except for this size difference and slightly thicker tail feathers of the male, both sexes look alike. Their stately appearance can give a false impression of size the males weigh an average of about 10-12 pounds and the females around 9 pounds. ![]() From wingtip to wingtip their outstretched wings can measure up to 7 feet. Sandhills are a tall, long legged, long necked gray bird with a bright red crown. The Sandhill crane, or Grus canadensis, is Michigan’s largest bird and its oldest living bird species. ![]()
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