While much of the long-wattled umbrellabird’s breeding biology is still unclear (9) (10), its courtship behaviour is known to be complex and elaborate (4) (9). Throughout the year, male birds can be found gathered at established sites, termed “leks”, where they make exuberant displays to the female birds (4) (10). The male uses a combination of raising its crest, swinging its wattle, and making grunting vocalisations to attract a mate (4). After mating, the female is solely responsible for building the nest, incubating the eggs and brooding the chicks (9) (10).
Puzzlingly, in at least one part of its range, male long-wattled umbrellabird displaying activity peaks during the dry season (August to December), around six months before the period of greatest female nesting activity (10). It is not yet clear why this disparity occurs, but possibly it is because the male relies on large quantities of fruit, which may be more abundant during the dry season, to sustain its energetic display (10). In contrast, when nesting, the female may be more dependent on the abundance of insects in the rainy season to give the energy and nutrients required to produce eggs and brood chicks (9) (10). In order to maximize chances of offspring survival at this time, it is thought that the female birds might either store male sperm for a long period after mating in the dry season, or they may mate with the small proportion of superior males still capable of displaying at the leks during the rainy season (10).
The consumption of large quantities of fruit means that the long-wattled umbrellabird plays an important ecological role within its habitat as a seed dispersal agent. Along with fruit, this opportunistic species will also take large insects, amphibians and reptiles (2) (8) (9).