G-iii 



TABLE OF CONTENTS 



Page 



1 . INTROCUCTION 1 



2. THE PHYSICAL ENVIRdNMENT 2 



2.1 Topography ' 2 



2.2 The Major Water Masses 3 



2.3 Meridional Circulation 3 



2.4 Longitudinal Circulation 6 



2.5 Detailed Circulation Patterns 8 



2.6 Ice 9 



2.7 Long-Term Variation in the Physical Environment 10 



3. PRIMARY PRODUCTION 12 



3.1 Controlling Factors 12 



3.2 Production Rates and Total Production 17 



4. ZOOPLANKTON 19 



4.1 Introduction 19 



4.2 Distribution 19 



4.3 Biomass and Production 25 



5. BENTHOS 27 



5.1 Introduction 27 



5.2 The Habitat 27 

 5»3 Faunal Associations and Zonation 27 



5.4 Biomass and Production 30 



6. KRILL 33 



6.1 Introduction and General Biology 33 



6.2 Distribution 35 



6.3 Grovrth and Life Span 42 



6.4 Reproduction 48 



6.5 Swarming 50 



6.6 Food and Feeding 54 



6.7 Production and Biomass 55 



6.8 Exploitation 5^ 



6.9 Stock Assessment 60 



6.10 Harvesting at Higher Trophic Levels 65 



7. CEPHAL0P0D3 69 



7.1 Introduction 69 



7.2 Biology 70 



7.3 Production and Biomass 72 



7.4 Exploitation 72 



7.5 Stock Assessment 74 



