156 FISHERIES OF THE NORTH SEA 



only the best species were used and the 

 rest destroyed. The United States fisher- 

 men also caught them when the fish were 

 migrating to the rivers through Puget 

 Sound and Juan de Fuca Strait, and rivalry 

 has somewhat reduced quantities until the 

 productivity now runs in cycles of four 

 years with lean years interspersed : the 

 salmon when four years old have the 

 irresistible instinct calling them to return 

 from the sea to the river of their birth, 

 and they move through the sounds into the 

 estuaries of the Fraser and Skeena to 

 spawn.- Every one knows that this beauti- 

 ful fish descends to the sea periodically, 

 but the distance covered by the migration 

 is not very great and the fish are generally 

 able to find their way back to the same 

 river from which they came. The salmon 

 feeds in the sea and spawns in the river, 

 and, although it will sometimes oblige 

 an angler by accepting the bait offered, 

 generally its one object, when in fresh 

 water, is to deposit its eggs and, if it does 

 not die soon after, return to the sea where, 

 like many other species, it finds its favourite 

 food in the vast quantities of herrings. 



