The Wattled Crane is the largest and rarest of the six crane species that occur in Africa. They are a winter-breeding, wetland-dependent species. Peak breeding activity occurs between May and August, although breeding activity has been recorded in all months of the year.
Active breeding pairs are year round residents of highland wetlands, sometimes using seasonal wetlands opportunistically or as post breeding dispersal areas. Pairs are strongly territorial and may defend territories several square kilometres in extent. The territories are highly specialized, comprising permanently inundated wetlands with predominantly sedge based vegetation. Prolonged disturbance at nests often results in failed clutches. The extended breeding period allows pairs whose first attempt at breeding was unsuccessful to re-nest (occasionally multiple times) within the same season.
The Wattled Crane’s reproductive rate is low, with the average clutch size being the lowest of any of the cranes. Pairs may lay either 1 or 2 eggs in a clutch, with the majority of the 2-egg clutches occurring in the KwaZulu-Natal population. The incubation period of Wattled Cranes is the longest of any crane, c. 36 – 40 days. Pairs have an 82 % hatching success rate, with the second egg acting as an “insurance policy” against the first not hatching. Regardless of clutch size, only one chick is ever raised, with the second egg being abandoned once the first has hatched.
The mean breeding success or mean number of chicks fledged per pair per annum is c. 0.67, with a 62.2% fledging success rate. Fledging takes 110 to 130 days. Juveniles remain with their parents for an extended period (+12 months), after which they are expelled from the breeding territory or are taken to a non-breeding floater flock (essentially occurs only in KwaZulu-Natal). Juveniles obtain full adult plumage after the first year, but may only reach reproductive maturity at 8 or 9 years.