OF THE SALMON. 25 



standing the scanty supply of food they can get in 

 these rivers. 



My next attempt was to ascertain the rate of their 

 growth during their short stay in salt water, and for 

 this purpose we marked spawned grilses, as near as 

 we could get to four pounds weight ; these we had no 

 trouble in getting with a net in the pools below the 

 spawning beds, where they had congregated together 

 to rest, after the fatigues of depositing their seed. 

 All the fish above four pounds weight, as well as any 

 under that size, were returned to the river unmarked, 

 and the others marked by inserting copper wire rings 

 into certain parts of their fins : this was done in a 

 manner so as not to interrupt the fish in their swim- 

 ming operations, nor be troublesome to them anyway. 

 After their journey to sea and back again, we found 

 that the four pound grilses had grown into beautiful 

 salmon, varying from nine to fourteen pounds weight. 

 I repeated this experiment for several years, and on 

 the whole, found the results the same, and, as in the 

 former markings, found the majority returning in 

 about eight weeks ; and we have never among our 

 markings found a marked grilse go to sea and return 

 a grilse, for they have invariably returned salmon. 

 We have now followed the spawned fish to the sea 

 and back again, and marked their progress during 

 that time. But before leaving the breeders, we may 

 just observe, that a plentiful spawning time, as is seen 

 in some seasons, when floods occur, often in July 

 and August, and when the upper parts of rivers are 

 perfectly full of fish, will never produce numerous 

 crops of smolts and grilses, unless it be accompanied 

 with other favourable circumstances. We may see a 

 great abundance of breeders, and yet the rivers, 

 during a great part of the spawning season, not in 

 the proper size to receive the seed to advantage ; it 



