FISH COMMUNITY STRUCTURE AND THE SPATIAL AND TEMPORAL

3,54
MB VARIABILITY IN RECRUITMENT AND BIOMASS PRODUCTION IN

378
stron CHESAPEAKE BAY

6617
ID University of Maryland

2002
rok

TABLE OF CONTENTS

LIST OF TABLES ix

LIST OF FIGURES.xiv

LIST OF ABBREVIATIONS xxii

CHAPTER 1

Introduction 1

REFERENCES. 5

CHAPTER 2

Spatial and temporal variability of pelagic fish community structure and distribution in Chesapeake

Bay, U.S.A 9

ABSTRACT . 9

INTRODUCTION 10

MATERIALS AND METHODS . 15

DISCUSSION. 46

ACKNOWLEDGMENTS 63

REFERENCES. 63

CHAPTER 3

Spatial distribution and recruitment of bay anchovy in Chesapeake Bay 105

ABSTRACT . 105

INTRODUCTION 106

METHODS. 109

RESULTS. 119

DISCUSSION. 128

ACKNOWLEDGMENTS138

REFERENCES. 139

CHAPTER 4

Production of bay anchovy in Chesapeake Bay . 167

ABSTRACT . 167

INTRODUCTION 168

MATERIALS AND METHODS . 172

RESULTS. 189

DISCUSSION. 195

ACKNOWLEDGMENTS216

REFERENCES. 217

CHAPTER 5

Fish biomass size spectra and production in Chesapeake Bay. 243

ABSTRACT . 243

INTRODUCTION 244

MATERIALS AND METHODS . 247

RESULTS. 252

DISCUSSION. 258

ACKNOWLEDGEMENT 270

REFERENCES. 270

CHAPTER 6

Conclusions 293

REFERENCES. 297

APPENDICES 299

Appendix I. Estimated mean pycnocline depths in Chesapeake Bay from 1995 to 2000. .300

Appendix II. Number and biomass per 20-min tow of major fish species (CPUE). N = Number, B =

Biomass (g), YOY = Young-of-the-year fish . 301

Appendix III. Relative baywide estimate of number and biomass of major fish species (CPUE). N =

Number (x106), B = Biomass (metric tons), YOY = Young-ofthe-year fish. . 303

Appendix IV. Modal analysis of bay anchovy in Chesapeake Bay from 1995 to 2000. Color

legends: gray – adults, black – first young-of-the-year YOY cohort, red – second YOY cohort, blue

– third YOY cohort, light gray – fourth YOY cohort. 305

Appendix V. Estimation of growth rate and mortality during the overwinter period (October-April) by

comparing October and April length frequencies of bay anchovy in Chesapeake Bay. 307

Appendix VI. Regional (lower, middle, upper Bay) estimates of annual mean biomass (B) and total

production (P) of pelagic and bentho-pelagic fishes in Chesapeake Bay from 1995 to 2000 based on

the observed B for each size-class and the allometric P/B relationship reported by Banse and

Mosher (1980). Prey is < 8 kcal, and predator is > 8 kcal body weight. 310

LIST OF COMBINED REFERENCES . 311