This research highlights the complexity of the cod mating system while providing an in-depth empirical analysis of reproductive success in Atlantic cod. I performed a comprehensive examination of reproductive success in Atlantic cod, Gadus morhua, at unprecedented temporal resolution, spatial scale, and sample size. The parentage analysis using eight microsatellite markers was performed on 4489 individual larval samples, from 73 wild-caught adults, obtained daily over a 91-day period. Size had a positive influence on all three correlates of reproductive success: the number of offspring fertilized, the quality of offspring produced and the timing of reproduction (i.e. duration and the number of batches). The mating strategy of cod played a critical role in determining the number of offspring fertilized for both males and females. I hypothesized that male size was fundamental in determining its rank within a dominance hierarchy, and subsequently, top-ranked males were able to dominate spawning events resulting in disproportionately high reproductive success. The three large females had unexpectedly low reproductive success, a trend I attributed to there being a lack of suitably sized males in the spawning basin. This research highlights the complexity of the cod mating system while providing an in-depth empirical analysis into multiple metrics of reproductive success.

A comprehensive handbook, covering all aspects of the Atlantic cod including the biology, ecology, life histories, behaviour, commercial exploitation and conservation Not only is Atlantic cod one of the most valuable food fish in the world’s oceans, it is an important component of North Atlantic ecosystems and has been subject to much research into its biology, ecology and exploitation. After hundreds of years of exploitation, overfishing in the last half of the 20th Century caused many stocks to collapse, most famously the Northern cod stock off Newfoundland and Labrador, Canada. Since then, most cod stocks have been better researched and managed, but remain in a variety of states, from fully recovered to continued decline. This book, written by world experts, describes that research and management, and the importance of cod and its fisheries on North Atlantic cultures and economies, with impacts well beyond the range of the species. Atlantic Cod: Bio-Ecology of the Fish offers insightful chapter coverage of cod nomenclature, taxonomy, phylogeny and morphology; physiology and ecophysiology; reproduction and spawning behavior; early life history and pre-recruitment processes; migrations, movements and stock identity; feeding, growth and energetics; the place of cod in the ecosystem; the exploitation of cod through history and present day commercial fisheries and precautionary management for sustainable fisheries; impacts of climate change on cod biology and ecology; and the future of the species and its fisheries. Discusses the major commercial importance of Atlantic cod through history Provides a comprehensive treatment of the bio-ecology of the most researched and highly exploited fully marine species Examines how the decline (and recovery) of cod stocks is of great political and scientific interest An essential purchase for marine fisheries scientists Atlantic Cod: Bio-Ecology of the Fish is a vital book for all fisheries scientists, managers and fish biologists.

Fish recruitment is a key process for maintaining sustainable fish populations. In the marine environment, fish recruitment is carried out in many different ways, all of which have different life history strategies. The objective of this book is to argue for greater linkages between basic and applied research on fisheries recruitment, and assessment and management of exploited fish stocks. Following an introductory chapter, this second edition of Fish Reproductive Biology is organized into 3 main sections: Biology, Population Dynamics and Recruitment Information Critical to Successful Assessment and Management Incorporation of Reproductive Biology and Recruitment Considerations into Management Advice and Strategies The authors collectively bring a wide range of diverse experience in areas of reproductive biology, fisheries oceanography, stock assessment, and management. Fully updated throughout, the book will be of great interest to a wide audience. It is useful as a textbook in graduate and undergraduate courses in fisheries biology, fisheries science, and fisheries resource management and will provide vital information for fish biologists, fisheries scientists and managers.