Found it this evening (sunday) and have taken it home. Pls send me a msg if its yours.
If it was sitting around one of the bollards near the notice board, I found it floating in the water bout half way out to the sand bank on Friday afternoon, I noticed it was still there today.
I suspect it may well have come off a stink boat or someone careless at point Walter ski area/beach and drifted there given the wind direction on Friday. Right spot for it to belong to a windsurfer though....
If it is that one and nobody claims it here, I'd say you might as well keep it. 
