This important publication provides, for the first time, a comprehensive review of knowledge of reproductive seasonality in teleosts. It addresses why a particular species should show such seasonality, and how environmental cues act as regulators to ensure that reproductive maturation and breeding occur at the optimum time. The book considers the ultimate factors responsible for the evolution of reproductive seasonality in fish. It reviews salient concepts of reproductive seasonality in mammals. This volume also includes a review of accumulated knowledge of the control mechanisms of salmonids, gasterosteids, temperate cyprinids, cyprinodonts and other brackish-water forms, and marine and tropical freshwater teleosts. This is a work of value to research scientists in the field of environmental physiology, reproductive biology, and comparative neuroendocrinology and endocrinology. In addition, it is relevant for institutions involved with aquaculture and fisheries management. It is useful for post-graduate as well as undergraduate courses in fish biology and various related subjects.