LIFE HISTORY AND HABITS 



the following spring. The difference in habits 

 must be due to selection of those which only stay 

 one winter here, because of the very hard and 

 destructive conditions in our rivers in the winter 

 time. In Scotland there is little ice frozen on the 

 bottom, and the little fish have a better chance. 



The growth of the salmon in the ocean is very 

 rapid, and has been subject to many studies in 

 England, where it has been observed by tagging 

 smolt and getting records from the tagged fish 

 when caught. They have been known to return 

 in nine to eleven months, weighing three and one- 

 half pounds as grilse, and in two years as ten to 

 twelve pound salmon, and in three years as twenty 

 to twenty-one pound salmon or even larger. Many 

 forty or fifty pound salmon have been found to be 

 returning to the river for the first time. 



It was supposed until recently that salmon al- 

 ways returned to the same river, but the marking 

 of the smolt has disposed of this theory. Salmon 

 tagged in one river have been caught returning 

 in other rivers. One fish marked in Nova Scotia 

 was caught in New Foundland. It is quite likely 

 that the fish which go far away from the mouth 

 of the native river to secure an adequate food sup- 

 ply may return to other rivers, while those which 



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