American Fisheries Society. 105 



THE QUALITY OF THE WATER A FACTOR IN 

 REARING TROUT FRY. 



BY C. C. WOOD. 



In rearing Brook Tront the temperature of the Avater is 

 TTSually the first important item to be considered. However the 

 quality of the water is also of great moment, and many who have 

 attempted to raise this fish have failed because the above item 

 had not been sufficiently considered, even if given a thought in 

 an intelligent manner. 



What is the quality of water necessary to successfully rear 

 this fish? A general answer might be, water that is pure and 

 cold ; and this in many cases would prove correct. 



But in what does the purity of the water consist? 



Will analysis determine whether the water is suitable for the 

 purpose or not ; were it pronounced pure ? 



I think that in many instances an analysis will prove little, 

 for wliile nothing may be detected injurious to the fishes it may 

 be found upon trial that the supply lacks much of the life-giving 

 properties necessary to the health of the fish. Again water of the 

 utmost purity may be entirely unsuited to the trout, while that 

 from a pond or lake, vseemingly unfitted almost for common use, 

 if of low temperature, as during the colder months of the year, 

 might furnish a splendid supply for the nursery ponds until 

 warm weather. 



In speaking of this subject I would like to consider the 

 difference, which no doubt many of you have noticed, in the 

 quality of the water from springs or streams, starting at no great 

 distance from each other. While on one the trout may be 

 healtliy, do well and grow rapidly, perhaps on the other, but a 

 few rods away it will be found impossible to make them live 

 after they have commenced to feed. x\nd yet both waters may 

 be pure and cold. 



Let us consider that the water has had sufficient aeration, 

 that the pools are not over-stocked and that the fish are treated 

 the same in each case; what shoiild cause the difference in 

 results ? 



