Breeding can occur year-round for the nankeen night heron, but its primary breeding season is October to May in Australia, February to June in Java, and February to May in the Philippines. The timing of the species’ breeding is also largely dependent on feeding conditions, such as food availability. Nankeen night herons typically nest in dense trees, but also nest in marshes and swamps. In areas without vegetation, the species can also build nests in caves and under rock overhangs. They often breed within large mixed-species colonies, which can include ibises, cormorants, other heron species, and spoonbills.