KINGDOM: Animalia (Animals)
PHYLUM: Chordata (Possessing a notochord)
CLASS: Aves (Birds)
ORDER: Gruiformes (Cranes)
FAMILY: Gruidae (Cranes)
SUB-FAMILY: Gruinae (Cranes)
GENUS: Antrhopoides (Blue Crane and Demoiselle Crane)
SPECIES: Anthropoides paradiseus (Blue Crane)
The Blue Crane is endemic to southern Africa, with almost all of the population occurring in South Africa. There are also small and declining breeding populations in northern Namibia and western Swaziland, although the population may now be extinct there. This crane further occurs in Lesotho, Zimbabwe and Botswana.
The Blue Crane is pale blue-grey in colour becoming darker on the upper head, neck and nape. The bill is ochre to greyish, with a pink tinge. The long wingtip feathers trail on the ground. The primary feathers are black to slate grey, with dark coverts and blackish on the secondary feathers. Unlike most cranes, it has a relatively large head and a thin neck. Juveniles are similar but slightly lighter, with tawny coloration on the head, and no long wing plumes.
Blue cranes are birds of the dry grassy uplands, usually the pastured grasses of hills, valleys, and plains with a few scattered trees. They prefer areas in the nesting season that have access to both upland and wetland areas, though they feed almost entirely in dry areas. Although historically found in areas of low human disturbance, the blue crane is currently thriving in the highly transformed agricultural areas of the Western Cape.
Blue cranes are omnivorous. They have a varied diet consisting of plant material such as small bulbs, seeds and roots, and animals such as insects (especially grasshoppers), small reptiles, frogs, fish, crustaceans and small mammals. They also eat fallen grains such as wheat and maize kernels, and lucerne leaves.
Blue cranes are a monogamous species (having one partner at a time). They lay their eggs in the bare veld, often close to water. The incubation stage lasts around 30 days. The young are able to walk after two days and can swim well shortly thereafter. They are fed primarily by their mother, who regurgitates food into their mouths. The chicks fledge at the age of 3–5 months. The young continue to be tended to until the next breeding season, at which time they are chased off by their parents.
During breeding, males defend the nest territory while the female incubates. There is a strict hierarchy in groups, with the larger adult males being dominant. They overlap in range with 3 other crane species.
Blue cranes generally live about 15 years in the wild but in captivity can reach ages between 20 and 30 years.
They are preyed upon by the Cape Clawless Otter (Aonyx capensis).
Cranes have been occasionally, illegally poisoned in areas where they are perceived as crop pests, or indirectly affected by poison aimed at other species causing crop damage. Collisions with power lines, as well as the removal of suitable habitat from the replacing of grassland with trees for commercial plantations, or wetlands drying out are currently the main threats to blue cranes. As human populations continue to increase, agricultural expansion, disturbance, persecution and livestock grazing also intensify and these threats are likely to become worse with time. Other threats include predation by dogs, and the illegal capture of chicks for food and for the pet trade.
Did you know?
- The Blue Crane is the national bird of South Africa
- The silver-bluish-grey plumage and long, dark wing feathers attracted the Zulu king, Shaka, and up to this day the present Zulu king wears head-feathers from the Blue crane
- The birds also associate with grazing herbivores, benefiting from the ability to grab prey items disturbed by antelopes and gazelle