Distribution and Habitat
The cranes have a cosmopolitan distribution, occurring across most of the world continents. They are absent from Antarctica and, mysteriously, South America. East Asia is the centre of crane diversity, with eight species, followed by Africa, which holds five resident species and wintering populations of a sixth. Australia, Europe and North America have two species. Of the four genera of crane, two, Balearica (two species) and Bugeranus (one species) are entirely restricted to Africa, and the third Anthropoides has one entirely African species and one species that is found in Africa, Asia and Europe. The remaining genus, Grus, contains the most species and is the most widespread genus, although only a single species occurs in Africa as a wintering migrant.
Most species of crane are dependent on wetlands and require large areas of open space. Most species of crane nest in shallow wetlands. Some species nest in wetlands but move their chicks up onto grasslands to feed (while returning to wetlands at night), whereas others remain in wetlands for the entirety of the breeding season. Even the two species of Anthropoides crane, which may nest and feed in grasslands (or even arid grasslands or deserts) require wetlands for roosting in during the night. The only two species that do not always roost in wetlands are the two African crowned-cranes (Balearica), which are the only cranes to roost in trees.
Some crane species are sedentary, remaining in the same area throughout the year, others are highly migratory, travelling thousands of kilometres each year from their breeding sites. A few species have both migratory and sedentary populations.
Read more about this topic: Crane (bird)
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