A crane nest is a tall structure of reeds, grass, cattails and other marsh plants. It is built by a pair of birds and resembles a large, cone-shaped mound. It can be placed on ground, in shallow water or even floating in the air. It is a communal effort and both male and female participate in gathering materials for the nest. It takes a couple of weeks to build and incubate a nest. Once the eggs hatch, a brood of chicks is born.The first chicks to hatch, known as poults, are very weak and easily killed by predators. The parents protect their young by calling to them, displaying their feathers and waving their heads to signal that they are still alive and alert. Parents also help break the egg shells and carry away shell fragments. The chicks emerge from the nest when they are ready, often within 24 hours.During the first two months, the chicks eat and sleep under their mother’s wings. They begin wing flapping and dancing when they are about three to four months old. After this they start flying with their parents and will migrate south with them at summer’s end.Once a crane chick has gained enough flight feathers to fly on its own, it becomes a juvenile. It loses its cinnamon-colored down feathers and acquires gray or white flight feathers. The juvenile plumage is replaced the next year when it molts into the adult winter plumage.Many factors affect a crane’s nest success or failure, including predation and flooding. The parents are adept at protecting their eggs and chicks, attacking predatory mammals (including raccoons, coyotes, bobcats and wolves) with a hissing sound, spreading their wings and kicking out. They also frighten other birds that might come too close to the nest, such as crows, magpies, owls and hawks.When crane chicks are very small, they undergo imprinting, a process whereby they identify their parents by following them around and imprinting on their behavior and appearance. This enables them to find their way back to the same place where they hatched. It is not well understood what other types of imprinting occur in cranes, but it likely includes sexual and parental imprinting. https://nestvui.com/bang-gia-to-yen-sao/ attempt renesting if their first nest fails. However, the success of a second attempt depends on how far into incubation the original nest failed and whether the pair was able to re-nest before the eggs hatched. This is a risky strategy because it is hard to tell which of the two eggs will survive. In addition, it is unlikely that a surviving chick will be fertile.

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