240 WHY SALMON LEAYE THE SEA. 



returned to the river in February, went down to 

 the sea before March, if, indeed, so early: of 

 course they would not increase in growth in fresh 

 water, though they would mend somewhat in 

 weight, after their weak spawning state. Setting 

 these, therefore, aside, it appears that the growth 

 of the last four fish averaged two pounds each per 

 month when they were at sea ; and if they re- 

 mained in the river after the 4th of March, as 

 it is reasonable to suppose they did, then their 

 growth must have been proportionably greater.' 



I will go back again to before spawning time, 

 and trace the habits of the salmon up to that 

 time. 



Salmon enter rivers from the sea as early as 

 February and March, for the sole purpose, it is 

 supposed, of spawning; but it must have some 

 other object in view as well, since at the earliest 

 the spawning process does not commence until 

 September. It cannot be for nourishment, be- 

 cause it is well known that salmon lose in weight 

 and condition every day they remain in fresh 

 water. Mr. Scrope goes on to remark, ' Some 

 think it is to get rid of the sea-louse ; but this 

 supposition must be set aside, when it is known 

 that this insect adheres only to some of the newly 

 run fish, which are the best in condition. I think 

 it more probable that they are driven from the 

 coasts, near the river, by the numerous enemies 



