I'd thought that Mother possum, with a young one in tow, was being a bit overprotective...
It seemed a reasonable thought, seeing the way she chased the other possums around...
"Is that a bird in the tree? I'd better go and let it know that I'm around and I'm not to be toyed with..."...
Which has resulted on several occasions with a cockatoo yelling at her to go away, possibly in a mildly terrified tone...
Um...
The old man bird was perched as high as he could be in the tree out the back...
Mother possum, some thirty feet below decided to transit across the tree...
In that position she's about as much threat to him as those frozen pies in the freezer are, ha ha...
But he yelled! Fit to rattle the windows... ha ha...
Mildly terrified? Yeah... I think I'm grasping the stick from the wrong end...
It seems that Mother possum is not horrible and aggressive and nasty, after all, and that it's a certain old man cockatoo who has what could loosely be termed an "attitude"... ha ha.
There was I thinking that poor old man bird certainly comes in for some flack, but even though he's in a vulnerable position he still gives as good as he can... he's a brave old man... ha ha
Who am I kidding? ha ha....
He's a loud mouthed old so and so... (I can't use the other word I was thinking of, not here... ha ha)...
At least next time the still of the night is torn by blood curdling shrieks I'll know it's not him that's in any hint of being in peril of any form, ha ha...
The ears of the neighbourhood, yes, the old bird? No, he's fine... and in fine voice, too... ha ha...
🙂
Right now, we are in the middle of a heavy winter rain pattern which is amazing for this time of year .. if nothing else, it has put the fires out and is refilling the dam ... 
