ODIMBAR (One Day I Might Be A Raptor) was not here on 5 April 2017, but had set up his court by 14 April. From behaviour we have considered that he is newly adult-fledged, but he could be an older bird who has shifted his court. It is autumn and the courting that dominates reporting on bowerbirds is not due till spring.

As we begin this blog on 16 April 2017, we already have our hearts in our mouths, concerned that this new family member outside our suburban bedroom window will survive the competition and that his court may thrive. His day is busy: hunting, building, learning, asserting, defending, charming, singing, raucous caucusing and dancing.

And the evidence before us, of daily life, is much more complex than what one usually reads or views on Youtube, of isolated males building bowers in spring to try to entice picky females with whom their relations are fleeting. It's not like that at all here.

Tuesday, July 4, 2017

Green bird's learning curve

In our last movie, a male and a female bowerbird were frustrated in their desire to practice courtship by green male bowerbirds challenging the mature black male bowerbird. Clearly antagonistic, clearly challenging the dark male. Could a green male overwhelm the black male at this point in the year and re-fledge by spring as a bower-king?

This adds to the intriguing question of how green males grow up, how they transform around age 7 into black mature males. I don't know if they all do change. I don't know what comes first, the behaviour or the physiological changes to a new character and a new role and a new colour.

In this movie, on the afternoon of 17 June, a different situation. On 11 May in this blog, Green Bird Afternoon showed a green male spending more than 20 minutes concentrating on being a grown-up, tending the bower, trying out tunes and dance steps. Today a movie almost 47 minutes long, actually covering more than an hour in which a green male had uncontested command of the bower. Odimbar, the black male, comes back briefly early in the movie, but there is no serious squabble and he leaves the bower after a short time, to return near the end of the film. It's as if he's happy to have had someone mind the bower while he went for a long lunch.

So we bring you Green Bird's Learning Curve ...  if this is the bird of 11 May, it's further up the curve. Or it may be a different bird with a different style and voice. But unlike the 11 May bird, it's not claiming 'squatters' rights'.

One of the things the green bird has done today is leave saliva on the twigs of the bower. There are two notions here. The bowerbirds' eyes see different wave lengths compared to humans and for these birds the twigs saliva treated are luminous. Whether different birds offer different luminosity etc... you need to consult a bowerbird-naturopath perhaps. But the other notion is that female bowerbirds sample the saliva on twigs in bowers as part of their assessment. So what are we to make of multi-saliva-ised twigs?

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