Goliath herons are very territorial, and rarely allow other individuals into their territory. More than one goliath heron is typically only observed if it is a breeding pair or if there are immature birds present. Breeding season is mainly during rainy season, but it can breed throughout the year in some areas. It may not breed every year, depending on conditions. It is predominantly a solitary breeder, but can in some areas breed in smaller colonies, as well as in colonies with other species of bird. Islands are often chosen as nest sites. Nests are large platforms of twigs and reeds, typically placed in trees, in bushes, or in reedbeds. The female lays 2-5 eggs, which are incubated by both sexes for 24-30 days. Both parents tend to the young, who fledge after somewhere between 40-80 days. Typically, only one or two of the chicks fledge.