Rosie at Buchan Log Cabins had said that the green-leafed twigs that littered the ground below the trees around the cabin (see branch in the upper right foreground) were due to black cockatoos and the flock of eight behaved a bit like the yellow-tailed blacks that have frequented Cumberland River in recent summers. They flew a purposeful track from the general direction of the caves reserve entrance road on the other side of Buchan River, perched high in another of the trees for maybe a minute and were gone again back towards where they had appeared from.

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The cabins are much elevated from the Google Street View in the same general direction.

The camera timestamped the picture at 3:28:45 GMT (1:28:45 pm AEST) on Thursday 21st August 2008. And while there is no photo record of the ensuing few seconds, I did see the birds a lot closer and their white wing tips were a dominant feature.

The problem is that Google search doesn't come up with any black cockatoos or similar sized black birds with conspicuous white wing tips. They very definitely weren't black swans which do have white wing tips that you mostly only see in flight. Nor were they currawongs whose white patches are in other places, and one of which I had hand fed less than an hour earlier, though it wouldn't stay around while I got my camera back out.

So the question remains: What bird is that?