"In writing this book about Crayfishes it has not been my intention to compose a zoological monograph on that group of animals ... I have desired, in fact, to show how the careful study of one of the commonest and most insignificant of animals, leads us, step by step, from every-day knowledge to the widest generalizations and most difficult problems of zoology; and indeed, of biological science in general."--The Preface

Aquaculture is now recognized as a viable and profitable enterprise worldwide. As aquaculture technology has evolved, the push toward higher yields and faster growth has involved the enhancement or replacement of natural foods with prepared diets. In many aquaculture operations today, feed accounts for more than one-half the variable operating cost. Therefore, knowledge of nutrition and practical feeding of fish is essential to successful aquaculture. This book is not written exclusively for scientists but also for students, practicing nutritionists, and aquaculturists. It covers the known nutrient requirements and deficiency effects for different fishes, and digestion and metabolism of nutrients and energy. It discusses nutrient sources and preparation of practical and research feeds. It gives directions for conducting fish nutrition and feeding experiments. Feeding practices for salmonids, channel catfish, tilapias, shrimps and hybrid striped bass are presented. Since the first edition of this book was printed, the National Research Council of the National Academy of Sciences has revised the nutrient requirements for fish. These revisions are in the present edition. Other additions to this revised edition are chapters on nutrition and fish health, and bioavailability of nutrients. Each original chapter has been meticulously revised and updated with new information. Aquaculture is a dynamic area and new technologies are being introduced continuously; therefore, some of the material discussed in this revised edition may become obsolete quickly. Nonetheless, the material presented has been thoughtfully selected and updated to make it of maximum use to persons whose interests range from general aquaculture to animal nutrition to feed manufacture.

Allows consumers make links between what they eat and the effect on the ecosystem and fishers globally. Stimulates dialogues among environmentalists, fishing industry, consumers.

Aquaculture the farming of fish and aquatic plants has become the world's fastest-growing food production sector, even as the amount of wild fish caught in our seas and freshwaters declines. From fish foods and pharmaceuticals to management of entire aquatic ecosystems, acquaculture is truly changing the face of the waters. Increased growth, however, brings increased risk, and aquaculture now lies at a crossroads. One direction points toward the giant strides in productivity, industry concentration, and product diversification. Another direction points toward the dangers of environmental degradation and the marginalization of small fish farmers. Yet another direction invites aquaculture to champion the poor and provide vital environmental services to stressed aquatic environments. 'Changing the Face of the Waters' offers a cutting-edge analysis of the critical challenges facing aquaculture, balancing aquaculture's role in economic growth with the need for sound management of natural resources. The book also provides guidance on sustainable aquaculture by evaluating alternative development pathways, placing particular emphasis on the application of lessons from Asia to Sub-Saharan Africa and Latin America. Aimed at policy makers, planners, and scientists, this book provides a comprehensive frame of reference for orienting ideas and initiatives in this dynamic industry.

"Society for Ecological Restoration"--Cover.

MANAGE WASTE AT LOWER COST WITH EMERGING NATURAL SYSTEMS Biologically-based waste management systems are emerging as a more reliable, less costly alternative to conventional energy-intensive mechanical process. If you're involved in planning, designing, building, upgrading or operating waste management facilities, Natural Systems for Waste Management and Treatment, Second Edition, by Sherwood C. Reed, Ronald W. Crites, and E. Joe Middlebrooks, can help you quickly evaluate and adopt one or more of these innovative technologies. Complete with performance data plus easy-to-follow design procedures (with example), it gives you a thorough working backgroud in: Wastewater stabilization ponds; Aquatic treatment systems; Feasibility assessment; Land treatment systems; Wetland systems; Site selection; Planning; Sludge management and treatment; On-site wastewater management; Much more.