Bower Power

What was that blue black bird that flew fast across to other trees as you approached the gardens? What are all those blue things on the ground just there?

The bird was likely the male Satin Bowerbird (Ptilonorhynchus violaceus). The blue objects are used to decorate the bower where he courts and mates with the female. Well females…male bowerbirds are not monogamous and may mate with any female that presents herself at the bower.

Here the male is checking his bower. Satin bowerbirds build what is known as an avenue bower – a double avenue of twigs or grass in arched walls, built on a platform of sticks on the ground. Inside the bower is often crusted with dried chewed leaves, wood pulp and even charcoal. They usually align north to south. Bowers may be neglected outside mating season but will be rebuilt in the same place from mid winter. Blue and yellow objects are favoured by the satin bowerbirds, the thought being this is because of the correlation with their plumage. These days the blue items are often plastic, though fruits, flowers and even feathers can be used.

This bower sits to the right of the main gate of the gardens and the male won’t be far away, as this is the centre of his universe. Approach quietly and you may see him rearranging the objects, adding touches to the bower, or even doing his mating dance. He removes anything that doesn’t match his colour selection. The items have been known to come from as many as 12 kilometres away.

It takes a full seven years for the male to move into the stunning blues of his adult plumage, but younger males will create practice bowers and practice their mating rituals.

This one was found just off the main path and this young male was putting on quite the performance.

First he picks up a leaf and then a blue object. He jumps and flares his tail and moves around quite provocatively. His head moves from side to side and often down. Waving the objects of choice around.

This chap has chosen a flower and a bottle top as his objects of choice. At this point it is worth mentioning that any loops from bottle tops should be cut before putting them into the bin. Whole loops can be caught around a birds throat and cause injury and even death. We all need to be aware that what we dispose of may be collected by a bird.

Here is a video of a young male practicing his courtship routine.

You may have noticed that these young males look very much like the females at this point. It is hard to differentiate between the two.

This is likely a young male curious about the main bower. The female is a dull green with rufous wings, underparts are off white and scalloped brown. Juvenile males appear as per the female for 4 years, but then the throat becomes greener and bill paler then odd blue feathers appear until 7th year full plumage. Both have blue/purple eyes.

This is either a young male or a female. If the couple successfully mate, the female will build her nest within a few hundred metres of the bower. They are shallow, saucer like constructions, often in the fork of a tree and made from sticks and lined with leaves. The female does all the feeding.

The other bird that is occasionally mistaken as a female bowerbird is the Green Catbird (Ailuroedus crassirostris). This is a catbird and the eye is one of the first things to look for to differentiate them from the satin bowerbird.

The satin bowerbird is regularly sighted at the gardens. Not so common is the Regent Bowerbird (sericulus chrysocephalus). The regent also builds an avenue style bower but generally in much denser areas.

This is either a female or young male regent bowerbird. Again the eye helps to give it away, plus the dark patch beneath the chin and the lack of green. Of course there is no mistaking the male.

His colours are stunning.

Bowerbirds are, indeed, unique. There are few species, other than humans, that can be said to create beautifully things, just for arts sake. Both their bowers and the surrounding decorations can be said to be works of art in their own right.

Sadly, habitat loss has seen them decline. In some locations it has caused them to raid fruit orchards where they have been shot and they are almost extinct in some areas of Australia. Thankfully they are abundant elsewhere and particularly in our gardens with no less than three satin bowerbird bowers spotted this season. Their diet consists of fruit, berries, seeds, leaves and insects and their larvae. They are important  seed dispersers for native seeds and fruits through excrement or regurgitation too.

We think they are just a little bit special and hope you do too.

Photos by Cheryl Cooper unless otherwise noted.