4. Western Atlantic 91 



a. Introduction 91 



b. Gulf of Mexico 91 



c. Straits of Florida 91 



d. East and North of the Bahamas 91 



e. Northeastern United States 92 



F. Feeding Activity During the Spawning Season ... 92 



G. The Spawning Act 92 



H. Maturity and Fecundity 92 



1. Age and Size at First Maturity: 92 



2. Fecundity 93 



3. Maximum Size at which Bluefin Tuna 



Spawn 94 



I. Discussion and Conclusions 94 



1. Mediterranean and Black Seas 94 



2. Eastern Atlantic 95 



3. Western North Atlantic 95 



4. Overall Situation 95 



VI. MIGRATIONS AND STOCK 

 IDENTIFICATION 96 



A. Introduction 96 



B. Methods and Materials, and Definitions 96 



1. Methods and Materials 96 



a. Deductive Methods 96 



b. Methods Used Mainly for Identifying 

 Stocks 96 



c. Methods Used Mainly for Studying 

 Migrations 96 



d. Development of Bluefin Tuna Tagging 96 



e. Summary of Bluefin Tuna Tagging 

 Programs 97 



2. Definitions 97 



3. Hypothetical Migration Model 97 



C. Studies of Migrations and Stock Identity 98 



1 . Mediterranean and Eastern Atlantic 98 



a. Introduction 98 



b. Migrations Between the Mediterranean 



and the Eastern Atlantic 99 



c. Migrations and Stocks within the 

 Mediterranean 104 



d. Migrations and Stocks in the Eastern 



Atlantic 108 



i. Large and Medium Fish 108 



ii. Small Fish 1 1 1 



iii. Very Small Fish 1 12 



2. Western Atlantic 1 13 



a. Introduction 113 



b. Large Fish 113 



c. Medium Fish 124 



d. Small Fish 127 



e. Very Small Fish 129 



3. Trans- Atlantic and Trans-Equatorial 

 Migrations, and Atlantic Stocks 129 



a. Introduction 129 



b. Trans-Atlantic Migrations 129 



i. Giant Fish 129 



ii. Medium Fish 130 



iii. Small fish 130 



c. Trans-Equatorial Migrations 132 



d. Stock Identification 132 



i. Biometric Studies 132 



ii. Biochemical Studies 132 



iii. Conclusions 132 



VIL DISCUSSION, RECOMMENDATIONS, 

 AND CONCLUSIONS 133 



A. Introduction 133 



B. Age and Growth 133 



C. Distribution, Migrations, and Spawning 133 



1. Introduction 133 



a Very Small Fish 133 



b. Small Fish 133 



i. Immature Individuals 133 



ii. Mature Individuals 133 



c. Medium Fish 133 



d. Large Fish 133 



2. Western Atlantic 134 



a. Very Small Fish 134 



b. Small Fish 134 



c. Medium Fish 134 



d. Large Fish 135 



3. Eastern Atlantic and Mediterranean 135 



a. Very Small Fish 135 



b. Small Fish 136 



c. Medium Fish 137 



d. Large Fish 137 



4. Comparison 139 



D. Identification of Stocks 140 



E. Recommendations 143 



VIII. BIBLIOGRAPHY 145 



A. Introductory Notes 145 



B. References 145 



IV 



