The blue crane (Grus paradisea), also known as the Stanley crane and the paradise crane, is the national bird of South Africa. The species is listed as Vulnerable by the IUCN.
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. They are altitudinal migrants, generally nesting in the lower grasslands of an elevation of around 1,300 to 2,000 m and moving down to lower altitudes for winter.
Of the 15 species of crane, the blue crane has the most restricted distribution of all. Even species with lower population numbers now (such as Siberian or whooping cranes) are found over a considerable range in their migratory movements. The blue crane is migratory, primarily altitudinal, but details are little known.
The blue crane is partially social, less so during the breeding season. There is a strict hierarchy in groups, with the larger adult males being dominant. They overlap in range with three other crane species but interactions with these species and other "large wader" type birds are not known. They are aggressively protective of their nesting sites during the nesting season, even attacking innocent, non-predatory animals such as antelope, cattle, tortoises, plovers and the smallest of birds, such as sparrows. Humans are also attacked if they approach a nest too closely, with the aggressive male having torn clothes and drawn blood in such cases. Threats to their eggs and chicks include large savannah and white-throated monitor lizards, egg-eating snakes, foxes, jackals, birds-of-prey, meerkats, and mongoose.
While it remains common in parts of its historic range, and approx. 26 000 individuals remain, it began a sudden population decline from around 1980 and is now classified as vulnerable.
In the last two decades, the blue crane has largely disappeared from the Eastern Cape, Lesotho, and Eswatini. The population in the northern Free State, Limpopo, Gauteng, Mpumalanga and North West Province has declined by up to 90%. The majority of the remaining population is in eastern and southern South Africa, with a small and separate population in the Etosha Pan of northern Namibia. Occasionally, isolated breeding pairs are found in five neighbouring countries.
The primary causes of the sudden decline of the blue crane are human population growth, the conversion of grasslands into commercial tree plantations, and poisoning: deliberate (to protect crops) or accidental (baits intended for other species, and as a side-effect of crop dusting).
The South African government has stepped up legal protection for the blue crane. Other conservation measures are focusing on research, habitat management, education, and recruiting the help of private landowners.
