At the Point Cook Coastal Park, there is pair of Black Swans that are always together, and almost always distinguishable from others in the area because of their behaviour together.
I was casually watching them, as they don’t do much really, just swan about together.
When on a sudden one of them arched up from the middle and sort of jumped up out of the water. Curious, but it quickly settled down again.
A few seconds later it did the same thing, and then a Little Pied Cormorant popped up out of the water along side it. The swan took a swing at the cormorant and it quickly submerged.
Then, the swan arched up again, and I figured out the cormorant must have been hitting or poking it underneath.
This time it was a bit too much for the swan, and it gave chase to the cormorant. And again it submerged and the swan gave another start, and the process repeated.
Perhaps the cormorant was gaining some underwater advantage from the bulk of the swan, or perhaps their movement stirred up the waters and the creatures.
Eventually tiring of it all the cormorant swam off, while the pair of swans went back to ‘swanning about’.