Clinical methods are presented for biological monitoring of hatchery and native fish populations to assess the effects of environmental stress on fish health. The choice of methods is based on the experience of the authors and the judgment of colleagues at fishery laboratories of the U.S. Fish and Wildlife Service. Detailed analysis methods, together with guidelines for sample collection and for the intrepretation of results, are given for tests on blood (cell counts, chloride, cholesterol, clotting time, cortisol, glucose, hematocrit, hemoglobin, lactic acid, methemoglobin, osmolality, and total protein); water (ammonia and nitrate content); and liver and muscle (glycogen content).

Application of the organophosphate insecticide Abate three times (at about monthly intervals) to duplicate 0.04 ha earthen ponds at 18 g/ha (4 micrograms/liter) -- the recommended application rate -- and 180 g/ha (40 micrograms/liter) caused no mortality on blugills. In ponds treated with 18 g/ha fewer bluegill fry were produced than in control ponds, brain acetylcholinesterase (AChE) activity was not affected, and accelerated growth of both fry and adults appeared to result from heavy feeding on dead or moribund Diptera larvae that resulted from the first two applications of Abate. The routine use of Abate at the recommended rate should have little adverse effect on fishery resources.

The proximate composition (percentage lipid, water, fat-free dry material, ash) and caloric content of eight species of Lake Michigan fish were measured: lake trout, coho salmon, lake whitefish, bloater, alewife, rainbow smelt, deepwater sculpin, and slimy sculpin. Except for alewives, proximate composition and caloric content did not differ significantly between males and females. Although the caloric content of all species varied directly with lipid content and inversely with water content, an increase in lipid content did not always coincide with a proportional increasein caloric content when other components of fish composition were essentially unchanged. This observation suggests that the energy content of fish estimated from the proximate composition by using universal conversion factors may not necessarily be accurate.

This book provides a survey of biochemical, physiological and histological biomarkers of environmental stress, along with evaluations of the strengths and weaknesses of various techniques for different applications. It features in-depth coverage of such topics as DNA adducts, acetylcholinesterase, ATP, endocrine mechanisms, blood chemistry, histopathological biomarkers, stress proteins, foreign and endogenous metabolites, metallothioneins, to name only a few. The book will be especially useful to toxicologists, biochemists, histologists, immunologists, risk analysis specialists, environmental managers, regulators, environmental scientists and engineers.

Twenty years ago, researchers wishing to identify contaminated areas in aquatic environments generally took water samples, and analysed them badly (as we have since discovered) for a few "pollutants" which were of topical note at the time (and which could be quantified by the methods then available). Today, the use of aquatic organisms as biomonitors in preference to water analysis has become commonplace, and many national and interna tional programmes exist around the world involving such studies. We believe that this trend will continue, and have complete faith in the methodology (when it is employed correctly). We hope that the following text assists in some part in attaining this goal, such that the quality of our most basic global resource -water - is adequately protected in the future. DAVE PHILLIPS, PHIL RAINBOW England, March 1992 vii Acknowledgements Our thanks for contributions to this book are due to several individuals and groups, for varying reasons. Firstly, a co-authored book is always a triumph, and we trust that the following text is an acceptable compromise of the views of two individual authors, on a complex and developing topic. Secondly, many of the ideas herein have crystallised over the last two decades as the field has grown, and we are individually and collectively grateful to a number of researchers for their insight and assistance.