This is a story about what are, in effect, mermaids and mermen. However, it is not fantasy – at least not fairy-tale fantasy, though perhaps you might class it as that SF sub-genre Speculative Fantasy, rather than as hardcore Science Fiction.
In one sense, it is a little of both – as I suppose are all the best SF novels.
In a not-too-distant future, when over-fishing has depleted the seas of wild fish, shoals of millions of farmed tuna are minded out in the open ocean by genetically engineered humans and tame dolphins. Like shepherds and their sheepdogs, the humans directing operations and the dolphins keeping the shoal all together and moving in the right direction. As a situation this clearly has its good side, but one of its downsides is that traditional fishermen, who had been barely making a living before, are now unable to compete. Some turn to piracy, or to drug-trafficking, working for the big cartels. Others, like our hero Toivo, struggle on as fishermen.
Toivo, it should be pointed out, is not a shepherd. What enables him to keep going is his ability to communicate directly with dolphins. He literally “speaks dolphinese”, which he learnt as a small child spending all his time with the dolphins that his father, a marine zoologist, was studying. Now his dolphin friends help him with his fishing.
So there he is on his fishing-boat somewhere out in the south Pacific. And not far away on a submersible raft, their home, live three shepherds. Two of them are a couple; the third, Olga, whom some would describe as beautiful, others as a freak, feels left out, lonely – and that she has nothing whatsoever to look forward to. She cannot live on land, and now her kind, mutants, the product of genetic engineering, have been declared illegal by the UN.
On a third vessel, a large ship, a fishing-boat skipper turned drug-runner who hates “swimmer freaks” sails towards them. Enough. I don’t wish to spoil it.
I have loved the whole notion of mermaids and sea-people all my life, so naturally I thrilled to this story. But there is something else that makes this book stand out from the rest. The dolphins are not only intelligent but philosophically and spiritually more advanced than most of us humans – partly, of course, because they are completely unmaterialistic. There is even the suggestion that their ancestors, millions of years ago, were land-dwellers and the first civilisation on Earth, but then took the conscious decision to return to the sea. Toivo’s close friend, the dolphin Poika, believes that humans have at last begun to tire of their materialistic and self-destructive civilisation and are now ready to return to the sea. That people like Olga represent the future of our species.