Sunday, July 8, 2012

>>Genus Ptilonorhynchus >Ptilonorhynchus violaceus (Satin Bowerbird)

Satin Bowerbird

Satin Bowerbird
Conservation status

Least Concern (IUCN 3.1)
Scientific classification
Kuhl, 1820
Species:P. violaceus
Binomial name
Ptilonorhynchus violaceus
(Vieillot, 1816)
The Satin BowerbirdPtilonorhynchus violaceus is a bowerbird endemic to eastern Australia.
A rare natural intergeneric hybrid between the Satin Bowerbird and the Regent Bowerbird is known as Rawnsley's Bowerbird.


The Satin Bowerbird is common in rainforest and tall wet sclerophyll forest in eastern Australia from southern Queensland to Victoria. There is also an isolated population in the Wet Tropics of north Queensland.


Like all bowerbirds, the Satin Bowerbird shows highly complex courtship behaviour. Mate choice in Satin Bowerbirds has been studied in detail by a group of researchers at the University of Maryland, College Park. Males build specialized stick structures, called bowers, which they decorate with blue, yellow, and shiny objects if these are available, including berries, flowers, and even ballpoint pens, drinking straws and other discarded plastic items. As the males mature they use more blue objects than other colours. Females visit these and choose which male they will allow to mate with them. In addition to building their bowers, males carry out intense behavioural displays called dances to woo their mates, but these can be treated as threat displays by the females. Nestbuilding and incubation are carried out by the females alone. Recent research has shown that female mate choice takes place in three stages:
  • Visits to the bowers, before nests have been built, while the males are absent
  • Visits to the bowers, before nests have been built, while the males are present and displaying
  • Visits to a selection of the bowers, after nests have been built, leading to copulation with (typically) a single male.
Experimental manipulations of the ornaments around the bowers have shown that the choices of young females (those in their first or second year of breeding) are mainly influenced by the appearance of the bowers, and hence by the first stage of this process. Older females, which are less affected by the threatening aspect of the males' displays, make their choices more on the basis of the males' dancing displays. It has been hypothesized that as males mature their colour discrimination develops and they are able to select more blue objects for the bower. It is not yet known whether this description would also hold good for other species of bowerbird.


Mature males have clear blue eyes and are uniformly coloured black, however, light diffraction by the surface texture of the feathers results in an almost metallic sheen giving a deep shiny blue appearance.Immature males are coloured and marked the same as females and are often mistaken for them.
Females might be mistaken for the Green Catbird or Spotted Catbird with distinctively green/brown or otherwise entirely brown upper body and lighter under body with a distinct reticulated or scalloped pattern, but with very striking lilac eyes.
Satin Bowerbird cunninghams.ogg
Cunninghams Gap, SE Queensland


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