Paradisaeidae – Birds-of-paradise

The Paradisaeidae (Birds-of-paradise, Manucodes, Sicklebills & allies) are a family of passerines; the majority of which are found in eastern Indonesia, Papua New Guinea, and eastern Australia. The members of this family are perhaps best known for the plumage of the males of the sexually dimorphic species (the majority), in particular the highly elongated and elaborate feathers extending from the beak, wings, tail or head. For the most part they are confined to dense rainforest habitat. The diet of all species is dominated by fruit and to a lesser extent arthropods. The birds-of-paradise have a variety of breeding systems, ranging from monogamy to lek-type polygamy. A number of species are threatened by hunting and habitat loss.

Crinkle-collared Manucode Manucodia chalybatus

They range in size from the King Bird-of-paradise at 50 g and 15 cm to the Curl-crested Manucode at 44 cm and 430 g. The male Black Sicklebill, with its long tail, is the longest species at 110 cm. In most species, the tails of the males are larger and longer than the female, the differences ranging from slight to extreme. The wings are rounded and, in some species, structurally modified on the males in order to make sound. There is considerable variation in the family with regard to bill shape. Bills may be long and decurved, as in the sicklebills and riflebirds, or small and slim like the Astrapias. As with body size bill size varies between the sexes, although species where the females have larger bills than the male are more common, particularly in the insect eating species.

Plumage variation between the sexes is closely related to breeding system. The manucodes and paradise-crow, which are socially monogamous, are sexually monomorphic. So are the two species of Paradigalla, which are polygamous. All these species have generally black plumage with varying amounts of green and blue iridescence. The female plumage of the dimorphic species is typically drab to blend in with their habitat, unlike the bright attractive colours found on the males. Younger males of these species have female-like plumage, and sexual maturity takes a long time, with the full adult plumage not being obtained for up to seven years. This affords the younger males the protection from predators of more subdued colours, and also reduces hostility from adult males.

Magnificent Bird-of-paradise Diphyllodes magnificus (female)

Wilson’s Bird-of-paradise Diphyllodes respublica

The majority of birds-of-paradise live in tropical forests, including rainforest, swamps and moss forest, nearly all of them solitary tree dwellers. Several species have been recorded in coastal mangroves. The southernmost species, the Paradise Riflebird of Australia, lives in sub-tropical and temperate wet forests. As a group the manucodes are the most catholic and flexible in their habitat requirements, with, in particular the Glossy-mantled Manucode, inhabiting both forest and open savanna woodland. Mid-montane habitats are the most commonly occupied habitat, with thirty of the forty or so species occurring in the 1000–2000 m altitudinal band.

Raggiana Bird-of-paradise Paradisaea raggiana – ©Nick Ludovic Green Bird-Photo-Tours ASIA

Short-tailed Paradigalla Paradigalla brevicauda – ©Nick Ludovic Green Bird-Photo-Tours ASIA

The diet of the birds-of-paradise is dominated by fruit and arthropods, although small amounts of nectar and small vertebrates may also be taken. The ratio of the two food types varies by species, with fruit predominating in some species, and arthropods dominating the diet in others. The ratio of the two will affect other aspects of the behaviour of the species, for example, frugivorous species tend to feed in the forest canopy, whereas insectivores may feed lower down in the middle storey. Frugivores are more social than the insectivores, which are more solitary and territorial.

Blue Bird-of-paradise Paradisornios rudolphin – ©Nick Ludovic Green Bird-Photo-Tours ASIA

Most species have elaborate mating rituals, with the Paradisaea species using a lek-type mating system. Others, such as the Cicinnurus and Parotia species, have highly ritualised mating dances. Males are polygamous in the sexually dimorphic species, but monogamous in at least some of the monomorphic species. Hybridisation is frequent in these birds, suggesting the polygamous species of bird of paradise are very closely related despite being in different genera.