The Salmon 85 



water, i.e. from the time a clean fish enters fresh water until it returns 

 to the sea. Some of them are a whole year in fresh water before 

 spawning, and, as nearly as I can make out, lose twenty-five per cent 





FIG. 84. 14 Ibs. 27th March. 



of their weight before and after this takes place ; so that a fish of 20 

 Ibs. leaving the sea on ist January 1907 is reduced to half that weight 

 on its return as a kelt on ist January 1908. This percentage varies 

 with the length of time the fish is in fresh water, and according to the 

 river it frequents. 



