With the decline in world fish stocks, our knowledge of fish reproduction has become fundamental. Reproduction is an essential commitment to future generation. It is also a continuous development process throughout ontogeny, requiring energetic, ecological, physiological, anatomical, biochemical and endrocrinological adaptations. The first chapters highlight important issues affecting fish normal ways of reproductive development; details would focus on species living in opposite environments, such as tropical and polar fishes; far related, as teleosts and cartilaginous fishes; and finally, fish having different reproductive strategies. Thereafter, since many fishes live in detrimental environments, mainly induced by the continuous input of xenobiotic substances into waterways, the authors found it highly pertinent to include this topic. Herein, the authors fix their attention on the factors and mechanisms that may well affect reproductionrelated hormonal systems as also on known consequences for fish living i

Marine fishes represent astonishing diversity with respect to practically every aspect of their biology. Reproductive modes and sexual patterns are especially fascinating and provide deep insight into general evolutionary problems. In this volume, chapters focus on reproduction and sexuality among groups of fishes defined by habitat, taxon, and the reproductive processes that are critical for reproductive success. The book illustrates how knowledge of reproductive biology among marine fishes can help identify vulnerable and potentially vulnerable species in the face of changing environmental conditions and increasing human-based pressures.

This book comprises a much needed review of recent developments and new ideas in fish reproductive biology, with special reference to the adaptive significance of reproductive patterns observed in teleost fishes. Based on a number of essays given at a meeting of the Fisheries Society of Great Britain the book presents a series of review articles, of international origin, covering aspects of theoretical modelling, ecology, behaviour and experimental laboratory studies. The final section of the book deals with some of the more commercially important aspects of fish reproduction with respect to aquaculture and fisheries biology. A comprehensive bibliography of relevant literature is provided. This well-illustrated work will prove to be of importance to those in fisheries management as well as fisheries scientists, fish and reproductive biologists.

With the decline in world fish stocks, our knowledge of fish reproduction has become fundamental. Reproduction is an essential commitment to future generation. It is also a continuous development process throughout ontogeny, requiring energetic, ecological, physiological, anatomical, biochemical and endrocrinological adaptations. The first chapters

Research on the molecular aspects of fish reproduction has progressed swiftly over the past few years. With the availability of wide-ranging molecular tools, fish researchers have elucidated many of the molecular mechanisms regulating reproduction which operate in the brain, pituitary and gonad. This research has revealed novel variants of reproductive hormones and their receptors, and has shed new light on the mechanisms through which many of these genes can be activated. Several of the findings, which are reported in this book, have formed the basis for subsequent mammalian research and will also constitute the platform on which new approaches to reproductive management in aquaculture can be developed.

Beach-spawning fishes from exotic locations on most continents of the world provide spectacular examples of extreme adaptations during the most vulnerable life cycle stages. The beauty, intriguing biology, and importance of these charismatic fishes at the interface of marine and terrestrial ecosystems have inspired numerous scientific studies. Adap

Comparative endocrinology is one of the most rapidly developing subdis ciplines within the field of endocrinology, and it is having a significant impact on research at the molecular, cellular, organisma1 and environmental levels. Much of the current ferment in endocrinology is in reproductive endocrinology. The purpose of this volume on hormones and reproduction in fishes, amphibians and reptiles is to summarize our present understandings and to identify important research problems to be addressed in the area of comparative reproductive endocrinology. It was inspired by the gathering at Copper Mountain, Colorado, of eminent endocrine scientists from around the world on the occasion of the Tenth International Symposium on Comparative Endocrinology in July, 1985. While preparing for that meeting, we decided that a special volume on reproductive endocrinology was needed to summarize what is known and to stimulate research in particular directions. Why do we emphasize fishes, amphibians and reptiles? First, knowledge about the reproductive endocrinology of these ectothermic vertebrates can provide a clearer picture of the evolution of reproductive hormones and their effects on target organs. This comparative approach can lead to new theories about the evolution of reproductive control mechanisms. Second, studies concerning the reproductive endocrinology of "lower" vertebrates can result in development of "model systems" for application to studies of birds and mammals. Indeed, information about the patterns of reproductive control in ectothermic vertebrates can tell us which are evolutionarily stable and which are labile.