Chapter XII Fish Migration 



THE movements of fish, like those of most 

 other animals, including Man, are dic- 

 tated principally by the food supply. 

 The lower an animal's status in the scale 

 of life the less is it the master of its fate, 

 and the movements of the vast fish 

 shoals present little analogy to those of 

 the ship-loads of human migrants or 

 even to the extensive wanderings of a 

 herd of antelope. The most independent 

 of fish are largely the helpless sport of 

 tide and wind. The movements of the 

 great ocean currents are principally re- 

 sponsible for the migrations of fish as at 

 present understood and that is very 

 imperfectly. Prior to the systematic 

 study of oceanography, a science still in 

 its infancy, the appearance of fish shoals 

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