 All species normally lay at least two eggs; the usual clutch size is one to three, rarely up to six.Both sexes incubate with the eggs on top of or below the feet; they may display when changing shifts.Incubation takes 30–36 days; hatching success for undisturbed pairs can be as high as 95%, but because of sibling competition or siblicide, in the wild, usually all but one nestling dies within the first few weeks (later in the pink-backed and spot-billed species).