The blue crane (Grus paradisea), also called the Stanley crane and the paradise crane, is the national bird of South Africa. This bird is listed as Vulnerable by the IUCN.
Description
The blue crane is a tall bird that lives on the ground, but it is smaller compared to other cranes. It is 100–120 cm (3 ft 3 in – 3 ft 11 in) tall, has a wingspan of 180–200 cm (5 ft 11 in – 6 ft 7 in), and weighs 3.6–6.2 kg (7.9–13.7 lb). Standard measurements include a wing length of 51.4–59 cm (20.2–23.2 in), an upper beak length of 8–10 cm (3.1–3.9 in), and a leg length of 20.5–25.2 cm (8.1–9.9 in). The bird is pale blue-gray in color, with darker feathers on the top of the head, neck, and back of the neck. The feathers from the crown to the area near the eyes are lighter, sometimes almost white. The beak is yellowish-gray with a pink color. Long wing feathers extend down to the ground. The main wing feathers are black or dark gray, with dark covering feathers and blackish secondary feathers. Compared to most cranes, it has a larger head and a thinner neck. Juvenile blue cranes look similar but are slightly lighter in color, with brownish feathers on the head and no long wing feathers.
Habitat
Blue cranes live in dry grassy areas, such as the grasslands of hills, valleys, and plains that have a few scattered trees. During the nesting season, they choose places that have access to both upland and wetland areas, even though they mostly eat in dry regions. These birds are altitudinal migrants, meaning they nest in lower grasslands at elevations between about 1,300 and 2,000 meters and move to lower elevations during winter.
Movements and behaviour
Of the 15 crane species, the blue crane lives in the smallest area of any. Other cranes, like the Siberian and whooping cranes, have smaller populations but travel over much larger areas during their migrations. The blue crane also migrates, mainly moving up and down mountains, though details about this behavior are not well understood.
Blue cranes are somewhat social, but they are less social during the time they breed. In groups, there is a clear order of dominance, with larger male cranes being the most powerful. Blue cranes share their habitat with three other crane species, but how they interact with these cranes and other large wading birds is unknown. During nesting season, blue cranes are very protective of their nests and may attack animals that are not predators, such as antelope, cattle, tortoises, plovers, and small birds like sparrows. They may also attack humans who get too close to their nests. In some cases, male cranes have torn clothing and caused injuries to people.
Threats to blue crane eggs and chicks include large savannah and white-throated monitor lizards, egg-eating snakes, foxes, jackals, birds of prey, meerkats, and mongooses.
Feeding
Blue cranes eat food from the ground and are seldom seen feeding near wetland areas. Most of their food is made up of grasses and sedges, and they eat different types depending on how close the plants are to their nests. They also regularly eat insects, such as grasshoppers. Small animals like crabs, snails, frogs, lizards, and snakes may add to their food. These protein-rich foods are often chewed up and given to their young.
Breeding
The breeding period depends on the season, with eggs being laid between October and March. Forming pairs often begins in October, as potential parents run in circles together. The male then performs a dance by throwing objects into the air and jumping. Eventually, a female from the group and the male choose each other, and both join in the dance of throwing objects and jumping. After the dance, mating occurs about two weeks later.
In most nests, two eggs are laid (sometimes one or three). Both parents take turns keeping the eggs warm, with the male often staying at night and the female during the day. The male also protects the nest area while the female incubates. The incubation period lasts about 30 days. The young can walk two days after hatching and swim well soon after. They are mainly fed by their mothers, who eat food and then spit it into the chicks’ mouths. The young leave the nest between 3 to 5 months old. They continue to be cared for until the next breeding season, when the parents chase them away.
Decline
The blue crane is still found in some areas where it once lived, and about 26,000 remain. However, its population began to drop quickly around 1980, and it is now considered vulnerable.
In the past 20 years, the blue crane has mostly disappeared from the Eastern Cape, Lesotho, and Eswatini. In the northern Free State, Limpopo, Gauteng, Mpumalanga, and North West Province, its numbers have dropped by as much as 90%. Most of the remaining blue cranes live in eastern and southern South Africa, while a small group lives in the Etosha Pan in northern Namibia. Sometimes, lone pairs of blue cranes are found in five nearby countries.
The main reasons for the blue crane’s sudden decline are human population growth, the change of grasslands into commercial tree plantations, and poisoning. Poisoning happens either on purpose to protect crops or accidentally, such as from baits meant for other animals or from spraying crops.
The South African government has increased legal protection for the blue crane. Other efforts to help the species include research, managing habitats, education, and working with private landowners.
The blue crane is one of the species protected by the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA).
Since October 2021, the Blue Crane has been classified as Moderately Depleted by the IUCN.
Cultural references
The blue crane holds cultural importance for the Xhosa people, who refer to it as indwe (flag). In the past, when a man showed bravery in battle or achieved great honor, a chief would often give him blue crane feathers during a ceremony called ukundzabela. Men who received these feathers, which were worn in their hair, were called men of ugaba (trouble). This name suggested that these individuals would help restore peace and order during difficult times.
The blue crane is also meaningful to the Zulu people, as their kings and warriors sometimes wore one or more feathers as part of their headdress.
Because of its connection to warriors and heroism, the Isitwalandwe Medal was created to recognize people who made significant sacrifices during the liberation struggle in South Africa (1949–1991). This medal honors those who opposed the apartheid regime in various ways. The name Isitwalandwe means "the one who wears the plumes of the rare bird," referring to the blue crane.
The blue crane is also recognized as the national bird of South Africa.