Cloud on Silver

Cloud on Silver is also known as Sweeney's Island.

A luxury cruise in the South Pacific comes abruptly to a halt when the yacht catches fire and sinks, leaving all the passengers marooned on an island totally isolated and inhabited only by the animals and birds one would expect. Or so it seems until they find the first of the freaks: a rat with two heads is seen, a lobster with one grossly over-developed claw, deformed pigs, mutated monkeys. And if some unseen agent on the island can transform its animal life, what effect will it have on a party of human intruders, beyond all hope of rescue and free from all the restrictions of morality?