Named after the white wattles dangling from its throat, this bird is the rarest and largest of the African crane species. They rely heavily on water, and are therefore an important indicator species in assessing changes to wetland hydrology. Unfortunately, as with most threatened species, the loss of their habitat and degradation of critical wetlands are threatening their continued survival. Furthermore, this delicate species has low breeding success, so proactive conservation is a priority for their survival.
It is found in eleven of the sub-Saharan countries of Africa, more than half of them in Zambia, with an isolated population in the Ethiopian highlands. The single largest population is in Botswana’s Okavango Delta. This bird largely depends on wetlands. It frequents large wet areas such as river basins in Zambezi and Okavango, and smaller seasonal and permanent wetlands in the highlands in Ethiopia and South Africa. These cranes breed in shallow wetlands that have sedges.
Habits and lifestyle
A Wattled crane is diurnal and spends most of its day foraging. It has a long bill and digs into soft soils and wetlands to feed. These birds are gregarious outside of the breeding season and gather in flocks of 10 or more birds, sometimes as many as 89. Juveniles display submissive behaviors in relation to the territorial adults. When they leave their parents, the juveniles join together to roost, and feed. The adults being highly territorial, juveniles seek new places elsewhere. Wattled cranes do not migrate, but perform some movements depending on water availability. Those living in the seasonal and upland wetlands usually move more than those in permanent wet areas. These birds are usually quiet. They have high-pitched calls that include a bugle-like call, a far-carrying kwaamk.
sedge, seige, herd
Diet and nutrition
Wattled cranes are omnivores, they mainly feed on vegetation and insects, occasionally eating frogs and snakes. Their main food source is sedge vegetation and water lilies.
Wattled cranes are monogamous and form pair-bonds that will often last for life. The building of a nest is part of the courtship ritual of a breeding pair, along with beautiful displays involving bowing, running, jumping and tossing plant items. This species breeds in wetlands where their nests are placed at least 500 m from the next one. The pairs become territorial and defend their territory with postures of threat and attacks on intruders. The breeding season is dependent on water levels and is July to August in Ethiopia, and April to October for the southernmost populations. A nest is a big mound of aquatic vegetation in the open water. 1-2 eggs are laid but usually just one chick is reared. Incubation is by both parents and is for about 33-36 days. When they hatch, the chicks can walk and swim, and they will follow their foraging parents while learning to feed themselves. Young grow rapidly and at about 3-4 months old they fledge. They stay in their family group until the next breeding period and mature between the ages of 4 and 8.
July-August in Ethiopia, April-October in the southernmost populations
The most serious threat to this species is the degradation and loss of wetland habitats, mostly caused by an increase in agriculture, industrialization, irrigation and dam building, which makes water levels fall. Increased human activity near breeding sites, is another major threat, as this decreases breeding success. These birds often feed in areas where there are blue and gray crowned cranes, which are perceived as crop pests, and are often illegally poisoned, putting the Wattled crane at risk from accidental poisoning. Other threats include collision with power lines and fences, natural droughts, illegal collection for food and being disturbed by livestock and dogs.
According to the IUCN Red List, the total Wattled crane population size is around 7,700 individuals. This includes 4,000-5,300 mature individuals. Currently this species is classified as Vulnerable (VU) and its numbers today are decreasing.
Fun facts for kids
- These birds often put their whole head under water when feeding.
- The nest of a Wattled crane can be as big as 120-180 cm in diameter.
- When chicks are threatened, they will hide in vegetation while the adults lead the predator away.
- Wattled cranes increase their size when irritated and when they are calm they decrease it.
- Breeding pairs are very aggressive when defending their territory and chicks, and will even attack humans.
- Ancient Greeks believed that the flight of cranes was the inspiration for the invention of the Greek alphabet by the god Hermes.
- The logo for Japan Airlines is the stylized nest of a crane.