The harbour at Manly has a shark net in the cove surrounding a section for swimmers who don't wish to contend with the rough and tumble (and sharks) of the ocean beach on the other side of the isthmus. The cove is wave free but the water was a little bit chillier than was comfortable on first plunge. It may be shark free, but it isn't for the squeamish swimmer. Several times I shared the shark netted space with small transparent jellyfish. They were disconcerting, but apparently harmless.