Elasmobranch - describes a group of fish without a hard bony skeleton, including sharks, skates, and rays.

This manual examines mathematical models applied in fish stock assessment, including models and variation rates; cohort models and analyses; stock fishing patterns, components, stock-recruitment relations, short- and long-term stock projections; fisheries resources management with regards to biological reference points and regulation measures; production models; estimation of parameters; and exercises.

Recent decades have witnessed strong declines in fish stocks around the globe, amid growing concerns about the impact of fisheries on marine and freshwater biodiversity. Fisheries biologists and managers are therefore increasingly asking about aspects of ecology, behaviour, evolution and biodiversity that were traditionally studied by people working in very separate fields. This has highlighted the need to work more closely together, in order to help ensure future success both in management and conservation. The Handbook of Fish Biology and Fisheries has been written by an international team of scientists and practitioners, to provide an overview of the biology of freshwater and marine fish species together with the science that supports fisheries management and conservation. This volume, subtitled Fisheries, focuses on a wide range of topics, including the history of fisheries science, methods of capture, marketing, economics, major models used in stock assessments and forecasting, ecosystem impacts, marine protected areas and conservation. It builds on material in Volume 1, Fish Biology, which ranges from phylogenetics and biogeography to physiology, recruitment, life histories, genetics, foraging, reproductive behaviour and community ecology. Together, these books present the state of the art in our understanding of fish biology and fisheries and will serve as valuable references for undergraduates and graduates looking for a comprehensive source on a wide variety of topics in fisheries science. They will also be useful to researchers who need up-to-date reviews of topics that impinge on their fields, and decision makers who need to appreciate the scientific background for management and conservation of aquatic ecosystems. To order volume II, go to the box in the top right hand corner. Alternatively to order volume I, go to: http://www.blackwellpublishing.com/book.asp?ref=0632054123 or to order the 2 volume set, go to: http://www.blackwellpublishing.com/book.asp?ref=0632064838. Provides a unique overview of the study of fish biology and ecology, and the assessment and management of fish populations and ecosystems. The first volume concentrates on aspects of fish biology and ecology, both at the individual and population levels, whilst the second volume addresses the assessment and management of fish populations and ecosystems. Written by an international team of expert scientists and practitioners. An invaluable reference tool for both students, researchers and practitioners working in the fields of fish biology and fisheries.

In Part 1, Manual, a selection of methods on fish stock assessment is described in detail, with examples of calculations. Special emphasis is placed on methods based on the analysis of length-frequencies. After a short introduction to statistics, it covers the estimation of growth parameters and mortality rates, virtual population methods, including age-based and length-based cohort analysis, gear selectivity, sampling, prediction models, including Beverton and Holt's yield per recruit model and Thompson and Bell's model, surplus production models, multispecies and multifleet problems, the assessment of migratory stocks, a discussion on stock/recruitment relationships and demersal trawl surveys, including the swept-area method. The manual is completed with a review of stock assessment, where an indication is given of methods to be applied at different levels of availability of input data, a review of relevant computer programs produced by or in cooperation with FAO, and a list of references, including material for further reading. In Part 2, Exercises, a number of exercises is given with solutions. The exercises are directly related to the various chapters and sections of the manual.