Form large colonies. Are generally monogamous, but are separated when they can not reproduce. Immature individuals accompany the adults during migration. They arrive at nesting sites in late September and early October, the couples meet and use the old nests or dig new ones. The mating takes place within the nest. In early November the adults leave the colony to feed and increase reserves to be used during incubation. Both parents incubate the egg and feed for chicken. By April the parents leave the nest and the chick does not eat until May when he can fly and take their food, soon after begins its migration.
It breeds between September and April. The nest is about 1 m long; it uses leaves in its construction. Puts one white egg, incubation takes about 52 - 55 days, chicks hatch in the third week of January.