Salvelinus species are one of the most thoroughly studied groups of fishes. Many reasons explain this intense interest in charr biology. Charrs have a Holarctic distribution encompassing many Asian, North American, and European countries and occupy diverse marine and freshwater environments. Furthermore, the current distribution of charr includes areas that were directly influenced by climate and topographic change associated with the many Pleistocene glaciations. Undoubtedly, these conditions have promoted much of the tremendous morphological, ecological, and genetic variability and plasticity within Salvelinus species and they make charr very good models to study evolutionary processes 'in action'. Many charr species also exhibit demographic characteristics such as slow growth, late maturity, and life in extreme environments, that may increase their susceptibility to extinction from habitat changes and overexploitation, especially in depauperate aquatic habitats. This vulnerability makes understanding their biology of great relevance to biodiversity and conservation. Finally, charr are of great cultural, commercial, and recreational significance to many communities, and their intimate linkage with human societies has stimulated much interest in this enigmatic genus. This volume comprises a selection of papers presented at the fourth International Charr Symposium held in Trois-Rivières (Québec, Canada), from 26 June to 1 July 2000. It includes 31 papers on ecological interactions and behaviour, trophic polymorphism, movement and migration, ecophysiology and evolutionary genetics, ecological parasitology, environmental stress and conservation. These studies cannot cover all recent developments in the ecology, behaviour and conservation of Salvelinus species, but collecting them into a special volume should bring attention to current research on this important genus and stimulate further work on Salvelinus species.

Proceedings of the International Symposium on Arctic charr held in Winnipeg, 4-8 May 1981, on the campus of the University of Manitoba.

At the end of the first international Symposium on Rotifers diately accepted to do this, and kindly made an entire in Lunz, Austria, September 1976, entousiastic pleas were special volume of its Journal 'Hydrobiologia' available made for a second gathering of possibly the same format for this purpose. Also, arrangements were made to have and spirit that had made the first one such a great success. the proceedings out as quickly as possible. The proceedings include all papers that were presented One of us (HJD), 'supported' herein by his friends Charles E. King and Jens Petter Nilssen in particular, tentatively in Gent, and two communications by collegues who could suggested that Gent University might host a meeting of not attend in person. They thus amount to 23 original con this kind, having in mind that since the Xlth congress of tributions, including the summaries of the workshops. All SIL in 1950, no other SIL activity had take places in have been reviewed by the editors, and many, in addition Belgium. In view of the relatively large number of Be1gian by one or more referees. Manuscripts have been adjusted, rotifer workers, many among which are or were active in wherever needed, for grammar, clarity of meaning, and Gent, this proposal sounded acceptable to the attendance length. However, where possible, the flavor of some per of the Lunz meeting, who then gave each other rendez sonal styles was left unaltered.

This important book draws together, for the first time, a vastwealth of information on all major aspects of the farming of Arcticcharr, a highly prized and commercially valuable salmonid. Theauthor, Gavin Johnston who has many years' experience of farmingArctic charr, teaching about and researching the species, hasproduced a book that is a landmark publication and an essentialpurchase for all those involved with the species. The book is broadly divided into three sections. The firstsection covers Arctic charr interactions with humans and thecharr's biological requirements for culture. Section two is apractical guide to the art and science of early-rearing Arcticcharr; a hands on application of current knowledge in Arctic charraquaculture. The final section of the book focuses on thecommercial production of Arctic charr, providing cutting-edgeinformation for all those involved in the exploitation of thisvaluable species. Arctic Charr Aquaculture is an essential purchase foranyone involved in, or considering involvement in farming of thisspecies. Farm managers and other personnel in fish farms andexperimental aquaculture units, fish and aquatic biologists willfind a huge amount of useful data in this book. Libraries in alluniversity departments and research establishments whereaquaculture, fisheries and fish biology are studies and taughtshould have copies of this book on their shelves. This book bringstogether for the first time the knowledge needed to farm and marketArctic Charr. Part One is an overview of Arctic Charr aquaculturebeginning with the history and development of Charr aquaculture,the biological attributes of Arctic Charr, the physicalrequirements for growth and commercial production requirements.Other chapters are devoted to Charr health, nutrition and feeding.Part Two is a practical guide for the producer operating an ArcticCharr farm either as a vertically integrated operation or asdiscrete hatcheries and grow out farms. Part Three is devoted tothe business of commercially producing Arctic Charr, and althoughit deals specifically with Charr it also covers many businessaspects of farming relevant to any fish species under cold watercultivation. It covers farm business management, the economics andfinance of Arctic Charr farming, marketing Charr products and aclosing section on how to avoid the pitfalls which others includingthe author have experienced.

The lake charr Salvelinus namaycush is a ubiquitous member of cold-water lake ecosystems in previously glaciated regions of northern continental U.S., Alaska, and Canada that often support important commercial, recreational, and subsistence fisheries. The lake charr differs from other charrs by its large size, longevity, iteroparity, top-predator specialization, reduced sexual dimorphism, prevalence of lacustrine spawning, and use of deepwater habitat. The species is remarkably variable in phenotype, physiology, and life history, some of which is reflected in its ecology and genetics, with as many as four morphs or ecotypes co-occurring in a single lake. The lake charr is often the top predator in these systems, but is highly adaptable trophically, and is frequently planktivorous in small lakes. The lake charr by their name highlights their common habitat, lakes both large and small, but often frequents rivers and occasionally moves into the Arctic Ocean. Movement and behaviour of lake charr are motivated by access to cool, well-oxygenated water, foraging opportunities, predator avoidance, and reproduction. Owing to their broad distribution and trophic level, the lake charr serves as a sentinel of anthropogenic change. This volume will provide an up-to-date summary of what is currently known about lake charr from distribution to genetics to physiology to ecology. The book provides a compilation and synthesis of available information on the lake charr, beginning with an updated distribution and a revised treatment of the paleoecology of the species. Understanding of ecological and genetic diversity and movement and behaviour of the species has advanced remarkably since the last major synthesis on the species over 40 years ago. Mid-sections of the book provide detailed accounts of the biology and life history of the species, and later sections are devoted to threats to conservation and fishery management practices used to ensure sustainability. A new standard lake charr-specific terminology is also presented. The book will be a valuable reference text for biologists around the world, ecologists, and fishery managers, and of interest to the angling public.