This classic text, whose First Edition one reviewer referred to as 'the ecologist's bible', has been substantially revised and rewritten. Not only have the advances made in the field since the Second Edition been taken into account, but the scope has been explicitly extended to all macroscopic animals, with particular attention being paid to fish as well as other vertebrates. Ecological Methods provide a unique synthesis of the methods and techniques available for the study of populations and ecosystems. Techniques used to obtain both absolute and relative population estimates are described, and approaches to the direct measurement of births, deaths, migration and the construction and interpretation of life tables are reviewed.Subsequent chapters examine those methods used for the measurement and description of biodiversity, species packing, energy flow and tropic relationships. The text is extensively illustrated, clearly describing a wide range of equipment and methods of analysis. Comprehensive and up-to-date bibliographies to each chapter fully cover the relevant literature, and references are given to available computer programs and internet addresses. Like the earlier editions, this book will be an indispensable source of reference to researchers and students at all levels in the fields of ecology, entomology and zoology. This book has an active website that provides additional illustrations, details of equipment and computer programs as well as references to work published since the manuscript was completed.