I go to the basin a lot as we have a mooring there. I assure you I have never seen a public buoy there. I reckon 90% of the boats are on moorings they have no right to be on so it is fine to pick up one. As one of the previous posts says, just vacate when asked. Having said that it is a bit funny, we have had several boats over the years come up to us and tell us we are on their mooring. They bank on the fact that most are there "illegally" and will move when challenged. It is a bit funny when I tell them we own the thing so they should go away. They invariably say something like "oh, I am sorry, I have picked the wrong mooring, our one is over there"