How to obtain it. 289 



Uself on its return from the river, and it has also to accumulate a 

 sufficient amount of fat to be of service to it during the time it 

 remains in the fresh water on its next visit. In going to the sea, 

 salmon get a thorough change of water as regards specific gravity, 

 temperature, composition, and products. The return of the fish 

 to the rivers is an exceedingly important economic question, some 

 rivers being early and some being late, and some, no wonder that 

 it should be so, are getting later. 



A great desire has been expressed from time to time to make 

 a late river earlier. The way to do this, if it can be done at all, 

 is to deal with the river as well as with the fish. The influences 

 which affect the habits and migrations of the salmon must be 

 carefully considered before attempting to deal with so difficult a 

 problem, but I would by no means discourage attempts to make 

 improvements in this direction. I have seen quite enough 

 myself to be led to the belief that it is quite possible to improve 

 some of our rivers that formerly were earlier than they are at 

 present. 



There are two main influences which more or less affect the 

 migrations of all fishes, viz., food supply and reproduction of 

 species. These are the primary elements to deal with in working 

 out any questions bearing on the improvement of fisheries. We 

 know that these items have a very important influence on their 

 welfare, and we know also that there is very much to learn 

 concerning them. In some cases the more we work out the 

 variety of facts connected with the migration of fishes, the more 

 complex do they seem. 



We have learned a great deal about the migrations of birds of 

 late years, but, living as they do in the air, we can to a great extent 

 follow their movements, by having observers all over a country or 

 continent, and so we ascertain their exact line of flight. It is not 

 so easy to follow the salmon through all his wanderings, but it is 

 a work that has to be done, and it is not very complimentary to 

 the advanced knowledge of the nineteenth century that we know 

 as little about the "king of fishes" as we do. 



We know that the salmon in the "parr" stage, as we find him 

 in our rivers before he has made any acquaintance with the sea, 

 feeds well. We know, also, that about the month of May these 

 u 



