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My experience of Satin Bowerbirds is that they
frequently use yellow flowers along Lady Carrington Drive in the Royal National
Park but not elsewhere. Obviously, it is all about availability.
Blue feathers, yellow feathers, blue berries and some
cicada shells, are popular along with man-made artefacts which include
straws and bottle tops wherever I go. Caged birds may take to all kinds of
abberant behaviour but as for wild birds killing other birds with
blue feathers; this is speculation or poetic licence.
In response to a couple of queries:
>certainly if a bird stops tending its bower, they very quickly get
stripped of the objects.
Bowerbirds will commonly steal off other birds in
adjoining territories and this can be part of constant material gathering war
for some individuals and often produces a great deal of transferal of
parpaphernalia across a wide area. these birds will spend their entire life
practicing their many courtship skills and rituals, such as dance, song,
mimicry, etc.. They also make the renovation of their bowers a constant concern,
along with a tireless search for the perfection of placement of paraphernalia.
Theft is part of this ritual. Around August each year it is not uncommon to find
every bower in a forest smashed to pieces by rival birds as they move toward the
breeding season. Perhaps the actual owner of the bower may do so in
preparation for renovation but I have not heard any robust evidence of this
being the case. Certainly other species I have observed like to keep
their bower in perpetuity, enhancing it every year.
>Apparently the more elaborate the bower, the
easier it is to attract a younger female. Older females aren't that easily
enticed therefore the male has to perform quite an elaborate dance to impress
her if she is the only female available. Is what I have heard wrong?
Interestingly, many human males might also note
this: It is the young female birds which are attracted to novelty. Older females
tend to be prepared to settle for old standards. It appears that this is a
considerable driving force in the evolution of the class, as males which wish to
entice the more fertile youngsters have to able to demonstrate considerable
fitness in order to be able to rise to the winner of the "race for novelty".
Thus we get bowerbirds, birds of paradise, Peafowl, Cock of the rock and
actually the entire myriad of not so subtle devices and behaviour employed by
male birds across the world in the courtship game. It's a fascinating area
of study.
Ricki
Broome Bird Observatory WA
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