Australian pelicans breed in large colonies, usually on islands or inland where there are few predators. Pelicans are seasonally monogamous, meaning that every breeding season they pair up with a mate and then stay with that mate for the rest of the season. The following breeding season they may or may not be with the same mate.
Courtship occurs when the local breeding population gathers at the breeding site. The large group breaks away into smaller groups consisting of a single female and two or more males. Within these smaller groups, males compete against one another for the attention of the female. Females lead the males in her group on courtship walks, swims, and flights, all the while the males display for her. The subordinate males will slowly break away and join other groups. Generally by the end of the ritual, only one male will remain. The pair will then land and begin designating a nesting site.
While the female pelican sits on the nest site, the male will perform a ritualistic display which may be followed with copulation. In order to mate the male must get on the female's back and then copulation will last from 6 to 22 seconds. They will mate several times over several hours. In between copulations the male will stand next to the female while she starts building the nest. Only after several copulations will the couple begin foraging for nest materials away from the nest.
Mating System: monogamous
Breeding usually occurs in winter or early spring, but may occur at any point in the year. Timing of breeding season is dependent upon rainfall and usually after rain events.
Australian pelicans lay approximately two, 172.9 g eggs per season, but clutch size can vary from 1 to 3. The eggs are elliptical in shape and range from 90 by 59 mm in size. Incubation lasts 32 to 35 days. At the time of hatching birds are altricial, feather-less and with eyes closed. In multi-egg nests, often one chick out-competes the others and is the sole survivor. After chicks leave the nest, they join large groups of up to 100 chicks also known as 'creches'. Chicks remain in these groups until they reach 2 months of age and are able to fly. Chicks do not reach independence for four months after hatching, when the parents stop regular feeding. Juvenile Australian pelicans reach sexual maturity at 3 to 4 years old.
Breeding interval: Australian pelicans breed once a year.
Breeding season: Australian pelicans generally breed from winter to early spring, but can occur any time throughout the year.
Range eggs per season: 1 to 3.
Range time to hatching: 32 to 35 days.
Average time to hatching: 32 days.
Average fledging age: 2 months.
Average time to independence: 4 months.
Range age at sexual or reproductive maturity (female): 3 to 4 years.
Range age at sexual or reproductive maturity (male): 3 to 4 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; oviparous
After pairs court and mate they then share the responsibilities of nest building, incubation, and feeding their offspring. During nest building both parents collect materials for the nest. Females will remain at the nesting site collecting nearby materials and forming a ground scrape, while the males will fly away as far as a mile to find materials for the nest.
After the eggs are laid, both parents share incubation responsibilities. Parents incubate by cradling the eggs on their feet. After hatching both parents alternate hunting for food. After 25 days chicks leave the nest and form creches and parents are able to leave the chicks alone for extended periods of time.
Australian pelican parents feed their young up to the first four months of the chick’s life. While still in the nest, chicks feed whenever they are hungry. When the chick leaves the nest to join a creche, they will only return to the nest when parents return to feed the chick After feeding, the chick will return to its creche. As the chick gets older the parents will feed their young on the edge of the creche. Once the chick becomes even larger it will leave the creche and join its parents some distance away to be fed.
Parental Investment: altricial ; male parental care ; female parental care ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Male, Female, Protecting: Male, Female); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female, Protecting: Male, Female); post-independence association with parents