Located about 10 hours south of Lihou Reef, Marion sits alone surrounded by several hundred metres-deep water of the southern Coral Sea. Compared to the reef we visited yesterday, this reef had a better fish diversity but was still suffering from bleaching and competition with surface algae. As well as encounters with graceful Manta Rays, this was a fantastic opportunity to swim with sea snakes. Sea snakes are even more maligned than sharks, crocodiles and the wealth of other 'dangerous' wildlife in tropical Australia but compared to their land-based cousins are surprisingly docile and approachable...even inquisitive, which both added an element of surprise and apprehension amongst most of our snorkellers and divers, many of whom had never encountered snakes, let alone at sea! They are truly remarkable animals. Less