Contents xiii 



Chemical Basis for Fertility 63 



Kinds of Fishes 63 



Growing Season 69 



Other Factors Related to Standing Crop Size 69 



Fish of Useful Sizes 70 



Fish Production 71 



Definition of Production 71 



Food Conversion 72 



Relation to Standing Crop 73 



Estimating Production 74 



Relative Plumpness of Fish 75 



Methods of Measuring Condition 76 



Coefficient of Condition 76 



Index of Condition 76 



Condition Factor of E. M. Corbett 77 



Condition Factor of Cooper and Benson 78 



Condition Cycles 78 



Condition and Growth Rate 79 



Use of Condition in Management 79 



Growth 79 



EflFects of Starvation 81 



Growth of Fish in New Waters 81 



Factors AflFecting Rate of Growth 82 



Interpretation of Growtli from Fish Scales 85 



Literature 89 



Chapter 5. Reproduction, Competition, and Predation 91 



Reproduction 92 



Reproductive Potential of Fishes 92 



Spawn Production and Number of Spawners 94 



Age and Sexual Maturity 96 



Sex Ratios 96 



External Sex Characteristics 97 



Spawning 97 



Hybridization 99 



Selective Breeding 101 



Unsuccessful Reproduction 103 



Stocking 103 



Fishes Used 104 



The Bass-Bluegill Combination 104 



Other Combinations of Fishes 107 



Changes in Fishing 110 



