Fish Ecophysiology

CHAPMAN & HALL FISH AND FISHERIES SERIES

Amongst the fishes, a remarkably wide range of fascinating biological adaptations to diverse habitats has evolved. Moreover, fisheries are of considerable importance in providing human food and economic benefits. Rational exploitation and management of our global stocks of fishes must rely upon a detailed and precise insight of the interaction of fish biology with human activities.

The Chapman & Hall Fish and Fisheries Series aims to present authoritative and timely reviews which focus on important and specific aspects of the biology, ecology, taxonomy, physiology, behaviour, management and conservation offish and fisheries. Each volume will cover a wide but unified field with themes in both pure and applied fish biology. Although volumes will outline and put in perspective current research frontiers, the intention is to provide a synthesis accessible and useful to both experts and non-specialists alike. Consequently, most volumes will be of interest to a broad spectrum of research workers in biology, zoology, ecology and physiology, with an additional aim of the books encompassing themes accessible to non-specialist readers, ranging from undergraduates and postgraduates to those with an interest in industrial and commercial aspects of fish and fisheries.

Applied topics will embrace synopses of fishery issues which will appeal to a wide audience of fishery scientists, aquaculturists, economists, geographers and managers in the fishing industry. The series will also contain practical guides to fishery and analysis methods and global reviews of particular types of fisheries.

Books already published and forthcoming are listed below. The Publisher and Series Editor would be glad to discuss ideas for new volumes in the series ...

Available titles

1. Ecology of Teleost Fishes Robert J. Wootton

2. Cichlid Fishes Behaviour, ecology and evolution Edited by Miles A. Keenleyside

3. Cyprinid Fishes Systematics, biology and exploitation Edited by Ian J. Winfield and Joseph S. Nelson

4. Early Life History of Fish An energetics approach Ewa Kamler

5. Fisheries Acoustics David N. MacLennan and E. John Simmonds

6. Fish Chemoreception Edited by Toshiaki J. Hara

7. Behaviour of Teleost Fishes Second edition Edited by Tony J. Pitcher

8. Genetics and Fish Breeding Colin R. Purdom

9. Fish Ecophysiology J. Cliff Rankin and Frank B. Jensen

Forthcoming titles

Fish Swimming J. Videler

Sea Bass G. Pickett and M. Pawson

Fisheries Ecology Second edition Edited by T.J. Pitcher and P. Hart

Hake Fisheries. products and markets. J. Alheit and T.J. Pitcher

Impact of Species Change in the African Lakes Edited by T.J. Pitcher

On the Dynamics of Exploited Fish Populations R. Beverton and S. Holt (Facsimile reprint)

Fish Bcophysiology

Edited by

J. Cliff Rankin and Frank B. Jensen

Institute of Biology Odense University

Denmark

CHAPMAN &. HALL London· Glasgow· New York· Tokyo· Melbourne' Madras

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First edition 1993

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Contents

Contributors xiii Series foreword T.]. Pitcher xv Preface Fish ecophysiology: the comparative physiologist's viewpoint

]. ClijJ Rankin and Frank B. Jensen xvii

1 Bioenergetics: feed intake and energy partitioning Malcolm ]obling 1.1 Introduction l.2 Basic principles 2 l.3 Factors influencing ingestion (R) ) l.4 Factors influencing faecal losses (F) 9 1.5 Products of nitrogenous excretion (U) 1 3 l.6 Factors influencing metabolism (M) 16 1.7 Factors affecting growth and production (P) 2 g l.8 Concluding remarks 3Y References 40

2 Biochemical correlates of growth rate in fish 45 D.P. Houlihan. E. Mathers and A. Foster 2.1 Introduction 45 2.2 Protein synthesis and growth 47 2.3 Perturbations in the general model 4Y 2.4 Protein synthesis and energy consumption 52 2.5 Free amino acids and protein turnover 54 2.6 Growth and its correlates in the tissues 56 2.7 Biochemical indices of growth rate 57 2.8 Linkage between aerobic enzymes and RNA 61 2.9 Body size efTects on protein growth. synthesis and RNA h2

concentrations 2.10 Temperature 64 2.11 Estimation of growth rate of fish in the North Sea 66 Acknowledgements 67 References h 7

viii Fish ecophysiology

3 Growth. reproduction and death in lampreys and eels 72 Lis Olesen Larsen and Sylvie Dufour 3.1 General introduction 72 3.2 Lampreys 73 3.3 Eels 86 3.4 General discussion 99 Acknowledgements 100 References 100

4 Salmonid smolting: a pre-adaptation to the oceanic environment 105 Gilles Boeuf 4.1 Introduction 105 4.2 Changes during parr-smolt transformation 107 4.3 Role of environmental factors 122 4.4 Conclusion 124 Acknowledgements 125 References 12 5

5 Role of peptide hormones in fish osmoregulation 137 Yoshio Takei 5.1 Introduction 137 5.2 Growth hormone (GH) 139 5.3 Angiotensin II (ANGII) 141 5.4 Arginine vasotocin (A VT) 143 5.5 Urotensins (UI and UII) 145 5.6 Vasoactive intestinal peptide (VIP) 147 5.7 Natriuretic peptides 149 Acknowledgements 153 References 153

6 Environmental perturbations of oxygen transport in teleost fishes: 161 causes. consequences and compensations Frank B. Jensen. Mikko Nikinmaa and Roy E. Weber 6.1 Introduction 161 6.2 Hypoxia 162 6.3 Combined hypoxia-hypercapnia 168 6.4 Temperature 169 6.5 Salinity change 17l 6.6 Effects of toxicants 172 6.7 Concluding remarks 174 Acknowledgements 175 References 1 75

7 Cardiovascular and ventilatory control during hypoxia 180 Regina Fritsche and Stefan Nilsson 7.1 Introduction 180

Contents ix

7.2 Chemoreceptors 181 7.3 Mechanoreceptors 187 7.4 Catecholamine release 187 7.5 Methods of studying ventilation in water-breathing animals 188 7.6 Ventilatory responses to hypoxia 189 7.7 Circulatory responses to hypoxia 194 7.8 General conclusions 199 Acknowledgements 199 References 199

8 Acid-base regulation in response to changes of the environment: 207 characteristics and capacity Norbert Heisler 8.1 Introduction 207 8.2 Environmentally induced changes of the acid-base status 208 8.3 Characteristics of regulatory responses 221 8.4 Capacity of acid-base relevant ion-transfer mechanisms 22 3

as a function of environmental conditions 8.5 Conclusion 22 6 References 22 6

9 Environmental effects on fish gill structure and function 231 Steve F. Perry and Pierre Laurent 9.1 Introduction 231 9.2 Environmental ions 234 9.3 Morphological component to acid-base regulation 249 9.4 Environmental pH and oxygen 255 Acknowledgements 258 References 258

10 Effects of water pH on gas and ion transfer across fish gills 265 David J. Randall and Hong Lin 10.1 Introduction 265 10.2 Proton excretion 266 10.3 Effect of water pH on proton transport 271 10.4 Interactions between proton, carbon dioxide and

ammonia excretion 271 10.5 Sodium uptake 272 10.6 Chloride uptake 272 10.7 Carbon dioxide transfer 27 3 10.8 Oxygen transfer 273 10.9 Ammonia excretion 273 lO.10 Swimming performance 274 References 274

x Fish ecophysiology

11 Endocrine responses to environmental pollutants 276 J. Anne Brown 11.1 Introduction 276 11.2 Adrenocortical response 277 11.3 Adrenergic responses 284 11.4 Prolactin 286 11.5 Thyroid response 288 11.6 Future studies 291 References 291

12 Branchial mechanisms of acclimation to metals in freshwater fish 297 D.G. McDonald and e.M. Wood

12.1 Introduction 297 12.2 Effects of metals on gill morphology 300 12.3 'Shock' phase 303 12.4 Branchial defences against acute metal toxicity 304 12.5 Recovery and the origin of metal tolerance 305 12.6 Increased tolerance via decreased metal accumulation

by the gills 307 12.7 Increased tolerance via increased metal storage and

detoxification in gill tissue 309 12.8 Increased tolerance via increased resistance of

metal-sensitive processes 311 12.9 Conclusions 312 12.10 Future research directions 314 Acknowledgements 315 References 315

13 Phenotypic plasticity of fish muscle to temperature change 322 Ian A. Johnston

13.1 Introduction 322 13.2 Muscle function and temperature 323 13.3 Temperature acclimation of swimming performance 325 13.4 Plasticity of muscle phenotypes 327 13.5 Muscle contractile properties 330 13.6 Muscle metabolism 335 13.7 Future prospects 337 Acknowledgement 337 References 3 3 8

14 Recent advances in the ecophysiology of Antarctic notothenioid fishes: metabolic capacity and sensory performance 341 J.e. Montgomery and R.M.G. Wells 14.1 Introduction 341

Contents

14.2 Respiration and metabolism 14.3 The cardiovascular system 14.4 The blood oxygen transport system 14. 5 Responses to stress 14.6 Sensory ecophysiology of notothenioid fishes 14.7 Ecophysiology and evolution of notothenioid fishes Acknowledgements References

15 Ecophysiology of intertidal fish c.R. Bridges

15.1 Introduction 15.2 The intertidal environment 15 .3 Temperature 15.4 Osmoregulation 1 5. 5 Respiratory adaptations Acknowledgements References

Author index

Subject index

xi

342 346 353 357 359 366 368 368

375

375 375 381 387 390 396 396

401

4})

Contributors

Gilles Boeuf IFREMER Centre de Brest, Station Ressources Vivantes, BP 70, 29280 Plouzane, France

c.R. Bridges Institut flir Zoologie, Lehrstuhl flir Tierphysiologie, Heinrich-Heine Universitat, Dusseldorf, Germany

J. Anne Brown Department of Biological Sciences, University of Exeter, Exeter EX4 4PS, United Kingdom

Sylvie Dufour Laboratoire de Physiologie, Museum nation ale d'Histoire naturelle, Paris, France

A. Foster Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB, Scotland

Regina Fritsche Department of Zoo physiology, University ofG6teborg, Box 25059, S-400 31 G6teborg, Sweden

Norbert Heisler Department of Physiology, Max-Planck-Institut flir experimentelle Medizin, Hermann Rein Str. 3, D-3400 G6ttingen, Germany

D. F. Houlihan Department of Zoology, University of Aberdeen, Aberdeen AB9 2TN, Scotland

Frank B. Jensen Institute of Biology, Odense University, DK-52 30 Odense M, Denmark

Malcolm Jobling NFH/University of Troms0, 9000 Troms0, Norway

Ian A. Johnston Gatty Marine Laboratory, Division of Environmental and Evolutionary Biology, School of Biological and Medical Sciences, University of St Andrews, St Andrews, Fife KY16 8LB, Scotland

Lis Olesen Larsen August Krogh Institute, University of Copenhagen, Denmark

xiv Fish ecophysiology

Pierre Laurent CNRS, Laboratoire de Morphologie Fonctionnelle et Ultrastructurale des Adaptations, 23 Rue du Loess, B.P. 20 CR, F-67037 Strasbourg Cedex, France

Hong Lin Department of Zoology, University of British Columbia, Vancouver, B.C., Canada

E. M. Mathers Department of Zoology, University of Aberdeen, Aberdeen AB9 2TN, Scotland

D.G. McDonald Department of Biology, McMaster University, Hamilton, Ontario, Canada

J. c. Montgomery Department of Zoology, University of Auckland, Auckland, New Zealand

Mikko Nikinmaa Department of Zoology, Helsinki University, Arkadiankatu 7, SF -00100 Helsinki, Finland

Stefan Nilsson Department of Zoophysiology, University of Goteborg, Box 250 59, S-400 31 Goteborg, Sweden

Steve F. Perry Department of Biology, University of Ottawa, 30 George Glinski. Ottawa, Ontario, Canada KIN 6N5

David J. Randall Department of Zoology, University of British Columbia, Vancouver. B.C., Canada

J. Cliff Rankin Odense Universitet. Biologisk Institut, Campusvej 55, DK-5230 Odense M. Denmark

y oshio Takei Laboratory of Physiology, Ocean Research Institute, University of Tokyo. Nakano, Tokyo 164, Japan

Roy E. Weber Zoophysiology Laboratory, Aarhus University, DK-8000 Aarhus C, Denmark

RM.G. Wells Department of Zoology. University of Auckland, Auckland, New Zealand

c.M. Wood Department of Biology. McMaster University. Hamilton, Ontario. Canada

Series foreword

Among the fishes. a remarkably wide range of biological adaptations to diverse habitats has evolved. As well as living in the conventional habitats of lakes. ponds, rivers, rock pools and the open sea, fish have solved the problems of life in deserts. in the deep sea. in the cold antarctic. and in warm waters of high alkalinity or of low oxygen. Along with these adaptations, we find the most impressive specialisations of morphology, physiology and behaviour. For example we can marvel at the high-speed swimming of the marlins. sailfish and warm-blooded tunas, air-breathing in catfish and lungfish. parental care in the mouth-brooding cichlids and viviparity in many sharks and toothcarps.

Moreover, fish are of considerable importance to the survival of the human species in the form of nutritious. delicious and diverse food. Rational exploi­tation and management of our global stocks of fishes must rely upon a detailed and precise insight of their biology.

The Chapman [.,. Hall Fish and Fisheries series aims to present timely volumes reviewing important aspects of fish biology. Most volumes will be of interest to research workers in biology. zoology. ecology and physiology but an additional aim is for the books to be accessible to a wide spectrum of non-specialist readers ranging from undergraduates and postgraduates to those with an interest in industrial and commercial aspects of IIsh and t1sheries.

Fish Ecophysio]ogy comprises the 9th volume in the Chapman b Hall Fish and Fisheries Series. The editors. Cliff Rankin and Frank B. Jensen. succeeded in assembling an impressive international group of 25 authors following a recent symposium held in Denmark. This 1 5-chapter volume of synthesis and review is the result of their efforts.

Whole living animals must live. survive and reproduce in balance with the natural environment. so physiological machinery is not only essential for survival but has evolved to intimately reflect the challenges I)f ecology. Unfortunately, despite the deep ecological awareness of such founding fathers as Claude Bernard. much physiological research has traditionally been

xvi Fish ecophysiology

reported in an introspective way that ignores the ecological context. The interdisciplinary approach of this book provides a refreshing perspective of a field where major conceptual advances will likely be made only by studies which cut across the boundaries of traditional disciplines. Furthermore, ecophysiological insight is critically important at the present time if we are to understand and mitigate ever-increasing man-made pollution in the delicate web of ocean life which has evolved on our planet.

In Fish Ecophysiology, two chapters tackle the major problem of how the partitioning of metabolic energy responds to changes in the environment; we need to understand the biochemical control mechanisms for the trade-oft's among energy allocated for swimming, digestion, growth and reproduction. A core of seven chapters examine environmental influences on oxygen transport, respiratory control, gill structure and function, acid base regulation, temperature change and muscle function, and regulation of water and ion balance. Two chapters examine physiological determinants of the intriguing pre-programmed life history strategies of migratory lampreys, eels and salmon. Two applied chapters address endocrine responses to pollution and how gills and the respiratory system respond to metals. The book ends with two integrated ecophysiolological case studies of antarctic and inter-tidal fishes, both groups that are challenged daily by environmental extremes.

Ecophysiology is a discipline endowed with hybrid vigour, sparkling with ideas and problems which cry out to be carried back to both its parent disciplines for detailed scrutiny. This book in the Fish and Fisheries Series will I trust make a major contribution to this process and serve as a valuable reference source for some years to come.

Professor Tony J. Pitcher Editor, Chapman & Hall Fish and Fisheries Series

Director, Fisheries Centre, University of British Columbia, Vancouver, Canada

Preface Fish ecophysio'logy: The

comparative physiologist's viewpoint

The vast range of habitats inhabited by fishes varies immensely with respect to biotic and abiotic factors. Successful maintenance of populations in chal­lenging environments requires responsive adjustments in physiology. Fish Ecophysiology describes how the physiology of fishes is affected by and regulated in response to environmental changes. It highlights acute problems imposed by environmental factors as well as physiological mechanisms in­volved in adaptation/acclimation to various environments. Such information is important to the understanding of the niche requirements of fishes. i.e. the limits of environmental factors within which animals can function and populations be sustained.

Ecophysiology forms the interface between ecology and physiology. over­lapping also with other disciplines such as behaviour and morphology. Accordingly, ecophysiological problems can be approached from many differ­ent perspectives (Jorgensen, 1983). The book does not presume to provide a complete synthesis, but by presenting various studies on interactions between fish and their environments, it is intended to contribute a better understanding of ecophysiological problems and how they are studied by different disciplines. Physiologists have always been interested in the exchanges which occur between organisms and the outside world. Exchanges of respiratory gases. food, salt, water, heat, sensory information etc. are basic aspects of animal physiology, and study of these processes has been one of the major preoccu­pations of physiology. This has been especially true in Denmark, as exemplified by the pioneering work of August Krogh, and when we decided to hold a fish physiology conference in Odense. where the University has a chair of ecophys­iology. 'Fish Ecophysiology' seemed a very appropriate theme. Additionally. we felt that the presentation and exchange of ideas across the many disciplines in which fish ecophysiologists work could be a rewarding event.

This book is not a proceedings from the conference held in Odense, 14-1 7 August 1991, but following the practice of previous International Symposia on Fish Physiology, we have asked some of the speakers to write chapters which will educate and inform those wishing to gain an insight into fish

xviii Fish ecophysiology

physiology as well as provide new research information for those who are already familiar with the field. In the interests of readability we have asked authors to limit the numbers of references cited. We hope that the book will be of interest to both physiologists and ecologists.

An important area of ecology is the study of energy flows through ecosystems. Physiologists studying metabolism are well aware of the many factors which can affect oxygen consumption, the most convenient measure of energy expenditure, and of the errors which may arise in applying data from laboratory experiments to the field situation. Chapter 1 on Fish Bioenergetics outlines the relationships between feeding and metabolism. Reliable methods of measuring growth rates in wild populations would obviously be extremely useful; this is addressed in Chapter 2. Study of the partitioning of resources between somatic growth and reproduction is essential to the understanding of life history strategies. In many fish the feeding/growth phase is temporally separated from maturation/reproduction, and study of extreme examples of this, such as in the eels and lampreys described in Chapter 3, may make understanding of resource partitioning easier.

Chapter 3 also illustrates the extent to which the endocrine system can bring about major changes not only in physiology but also in morphology and behaviour, resulting in a complete switch in mode of life. One of the best examples of this is provided by the story of salmonid smoltification, told in Chapter 4. Smoltification is considered as a 'pre-adaptation' to marine life which occurs at a certain stage in the development of juvenile fish. All the changes in physiology, biochemistry, morphology and behaviour can be brought about by injection of growth hormone. Some interdisciplinary con­fusion may arise from the differing usage of the word 'adaptation'. Evolution­ary biologists see adaptations as properties of organisms arising gradually by natural selection, which fit them for life in particular circumstances. Physiol­ogists study 'adaptations' defined in this restricted way, but also use the word in its ordinary English sense (defined by one dictionary as "the ability of an organism to cope successfully with its environment") on a shorter time scale and are familiar with, for example, adaptation of nerve cells within seconds to repeated stimulation or adaptation to seawater by migratory fish within days of entering it. The latter could be called acclimatization but, whilst this is a process which can lead to adaptation (in the physiological sense), in the instance described above genetically pre-programmed hormone release can ensure that salmonids are adapted to life in seawater without any acclimati­zation to it. Unfortunately the term in general use amongst physiologists to describe this, preadaption, has a specific and quite different meaning to evolutionary biologists. Perhaps new terminology is required.

Fish endocrinology provides examples of the enormous latent phenotypic adaptability of animals which can be triggered by hormonal stimulation. Until recently much research involved injecting mammalian hormones or using radioimmunoassays developed for higher vertebrates. In recent years much

Preface xix

progress has been made in characterizing fish hormones and developing homologous radioimmunoassays, and the subject has progressed to the point where a peptide hormone produced by the ventricle of the heart has first been identified and sequenced in fish (Chapter 5).

The respiratory physiology of fishes is afl'ected by numerous physical-chem­ical factors in the environment, including 02 and C02 tensions, temperature, salinity and toxicant levels. Chapter 6 describes how the flow of oxygen from environment to cells can be perturbed at different steps and levels of organi­zation in the gas transport system, and how various molecular, cellular and organismic mechanisms act in concert to compensate for these perturbances. One prerequisite for proper behavioural or physiological responses to be elicited in response to hypoxia is that fish are able to acquire and process information about 02 changes. Sensing of oxygen changes and the transfer and integration of information related to ventilatory and cardiovascular control are considered in Chapter 7.

The acid-base status of fishes is strongly dependent on environmental factors, and mechanisms are needed to correct acid-base disturbances in extra­and intracellular body compartments in order not to impair metabolic pro­cesses. The characteristics and capacity of acid-base regulatory mechanisms are the subject of Chapter 8. Focus is on transepithelial transfer of acid-base equivalents and its dependence on environmental ion composition. The gill is a multifunctional organ involved in gas transfer, acid--base balance and ionic/osmotic regulation. Chapter 9 addresses the relationships between gill morphology and function, highlighting how gill morphology and ultrastruc­ture depends upon environmental factors and how changes in morphology contribute to acid-base regulation.

Water pH is an important factor affecting both the physiology and the ecology of fishes. This has become increasingly recognized by the extensive environmental acidification of soft freshwater habitats in recent decades. which has resulted in extinction of local fish populations, altered species diversity etc. The mechanism of acid excretion across fish gills and its dependence on water pH is the subject of Chapter 10, whereas Chapter 11 describes the endocrine responses to environmental acidification and to other environmental stressors such as aluminum in acid water.

Wash out of aluminum from soil by acid rain represents just one example where aquatic ecosystems have been contaminated with metals Anthropo­genic activity has meant that other metals can also reach toxic levels in certain habitats. Aluminium and other metals exert their prime toxic action on the gills of fish. These effects are described in Chapter 12, and the quest ion to what extent fish can acclimate to metals is discussed.

Temperature has a profound effect on all physiological processes, and fish are constrained by the temperature of the ambient water (apart from a few very active species that can keep their swimming muscles warmer). There may, however, be considerable scope for phenotypic adaptation to different

xx Fish ecophysiology

water temperatures (Chapter l3). In the Southern Ocean, temperatures are uniformly low, and Antarctic fish are ideally suited for the study of how adaptations to an extreme environment have evolved during the radiation of a closely related group of animals (Chapter 14). Of course, not all special features found will be adaptations. Antarctic icefish have lost the respiratory pigments found in all other vertebrates, and it has been tempting to see this as an adaptation to life at very low temperatures by having reduced blood viscosity as a result of the absence of red blood cells. However, the reduced viscosity is much more than counterbalanced by the necessity to pump very much more blood to carry the same amount of oxygen in physical solution. More likely they survived losing expression of the haemoglobin gene because the high oxygen solubility and their low oxygen consumption meant that an adequate (but not perfect) performance could be maintained by developing the other features of their circulatory system described in the chapter.

The final chapter presents information on the ecophysiology of fish in a particularly extreme habitat, the intertidal, in which they are challenged by large diurnal variations in many of the environmental variables described in the other chapters, such as temperature, salinity, and oxygen and carbon dioxide tensions.

We are most grateful to the following for making it possible to bring authors from all over the world to Odense for the Symposium: The Danish Natural Science Research Council, The Munke M011es Foundation, The Natural Science Faculty of Odense University and The Carlsberg Foundation.

REFERENCE

J. Cliff Rankin Frank B. Jensen

Jorgensen. C.B. (1983) Ecological physiology: backgrounds and perspectives. Compo Biochem. Physiol.. 75A. 5-7.