THE SALMON FAMILY 65 



" grilse kelt," returning to sea early the next year con- 

 siderably diminished in weight. 



The grilse kelt in the sea becomes a salmon, and may 

 return in another year, though more often in two years' 

 time, to spawn as a salmon, returning to the sea as a 

 kelt. 



Salmon seldom spawn more than twice in their lives, 

 and they have not, up to the present, been found to 

 return after eight or nine years of age. Either salmon 

 do not spawn after this age, and therefore do not return 

 to fresh water, or eight or nine years is their natural span 

 of life. 



There are many irregularities in the journeyings of 

 a salmon. For example, fish may not return to fresh 

 water at all until the fifth, or even sixth, year of their 

 lives. 



Salmon certainly grow very rapidly, but there has 

 been considerable exaggeration as to their actual rate 

 of growth. A spring fish coming into fresh water for 

 the first time during the fifth year of life usually weighs 

 twelve to twenty pounds, but as an exception a fish 

 can weigh thirty-five pounds at the beginning of its 

 fifth year ; that is to say, it can put on weight at the 

 rate of one pound per month in the sea, taking into 

 account summer and winter growth. 



A journey into fresh water to spawn of course pre- 

 vents the fish increasing in weight as fast as if he 

 remained the whole time in the sea. 



The salmon found QD the Pacific Coast of America, 



