The sun is definitely lower now. The freezing thermocline in whose upwelling the swimmer was briefly caught has moved on. He is thirsty and weary and finds himself becalmed in an edgy resignation. He has done his purposeful but unrewarded swimming about. Now he wants to preserve his strength for staying alive as long as possible. He is already thinking ahead to another day's floating, taking for granted that he will survive the night.
For the first time he is considering the possibility of rescue. He has abandoned the idea of finding his boat. He accepts that his directionless first attempts to search for it are more likely to have separated him still further. Even if he did happen to be looking in the right quarter when stern or prow or the tip of an outrigger reared up on a wave, there are surely too many intervening waves for anything to be visible now.
He does have a plan of sorts, if that is not too intentional a word for such an impotent state as his. At nightfall, he knows, this area becomes a major local fishing ground. True, many of the boats will have engines over whose unsilenced blatter his shouts may not be heard. But many of the poorer fishermen stop their engines to save fuel and just drift, while the poorest of all will come out here under sail. Since sound travels well over water the swimmer has high hopes that someone will hear.
In the meantime he is once again examining the sunlit depths on the extreme off-chance of rescue from another source. He has heard legends of dolphins helping shipwrecked mariners, of a strange bond which sometimes leads them to aid distressed humans, even occasionally towing them to safety. The sea is empty, however. It seems to him it is a long time since he has even glimpsed a dolphin, several weeks at least. He can remember when it was hardly possible to look at the sea for five minutes in these parts without their breaking the surface, leaping in pairs. Only three or four years ago he would probably have been surrounded by the curious and playful creatures. Now there is nothing. The sea is empty even of their squeaks. The swimmer knows their absence is most likely due to the very fishermen at whose hands he is hoping for deliverance. Why should any remaining dolphin come within a mile of him? Of what use now to invoke "strange bonds" in so self-interested a fashion when the deal had always been so cruelly one-sided?
James Hamilton-Paterson, Seven-Tenths: the sea and its thresholds