The Blue Crane is the national bird of South Africa and the symbol of one of the most important royal houses on the African continent, that of the Zulus. Although still abundant in parts of its historic range, the Blue Crane has experienced significant declines in many areas over the past couple of decades and has now officially been classified critically endangered by the IUCN.
The Blue Crane's distribution is the most restricted of the world's fifteen crane species. It is endemic in southern Africa, with the over-whelming majority of its extant population occurring in eastern and southern South Africa. A small disjunct population occurs in the Etosha Pan of northern Namibia, and breeding pairs are occasionally found elsewhere in southern Africa.
Historically, this graceful bird with flowing bluish plumage sweeping to the ground, was found throughout South Africa with flocks of up to 1000 birds seen in parts of its range. This included the Eastern Cape Province, northern Orange Free State, the southern and eastern areas of the former Transvaal and western Kwazulu-Natal. As recently as 1980, there was little concern about the Blue Crane from a conservation standpoint.
However, the species has now withdrawn from the former Transkei region, most of Swaziland as well as the lower-lying areas of Lesotho. In some of these areas, the populations have declined by with as much as 90%. It seems most of the decline occurred in areas of intensive crop farming. The total population is estimated at 21,000 and is declining.
The Blue Crane is essentially a bird of dry, upland grassland. In South Africa, it is largely restricted to three biomes - the grasslands, semi-arid Karoo and fynbos. Within the grasslands, the species is more evenly distributed in the eastern "sour" grasslands, where small stock farming is predominant than in the central and western grassland (predominantly crop farming).
In the arid Karoo, the Blue Crane are found in areas where perennial grasslands are dominant over the more typical Karoo shrub lands of the area. In the fynbos biome, the species is almost exclusively restricted to the cultivated habitats (mainly cereal and small livestock areas).
The habitat use varies amongst the different regions, depending on the time of year and availability of food. Principal food items include the seeds of grasses and sedges, waste grains, insects and small vertebrates.
The birds use grass- and sedge- dominated habitats for both nesting and feeding, but will roost in wetlands if available. Blue Crane nest during the summer months (September to February) and preferred nesting sites are secluded grasslands, where the eggs are laid on the bare ground or amid the grass. They will also, where local conditions dictate, nest in agricultural areas. Here they nest in pastures, fallow fields, and crop fields after harvesting has commenced. Usually two eggs are laid, with and incubation period of 30 - 33 days.
Blue Cranes have been known to have seasonal movements within South Africa, but limited research has been done on this aspect. Recent studies have suggested that a general increase in numbers in both the Karoo and Overberg areas, but this may be an artifact of their flocking behaviour during the non-breeding period pattern of movement into the Karoo biome during the winter. Flocking can occur year-round, but intensifies during the winter, when groups of several hundred birds form.
Intentional and unintentional poisoning, afforestation of South Africa's grasslands, and the impacts of growing human population pressure constitute the most significant threats to the Blue Crane. As the threats to the Blue Crane's survival have multiplied, happily so have the efforts to conserve the species.
The future of the Blue Crane is not rosy, but much is being done to ensure its survival.