106 Thirtieth Annual Meeting 



In one case a splendid success ; in the other an utter failure. 

 This is not an easy question for one to answer and I shall not 

 make the attempt. Perhaps some of you present may be able to 

 tell just what the trout require, what quality of water is best 

 suited to them. 



Many trout breeders, soon after the fry are hatched find it is 

 impossible to retain them in the hatching boxes without great 

 loss, but that if removed to pools out of doors a fair degree of 

 success may be attained on the same water supply. In such cases 

 I should be inclined to think that insufficient aeration was given 

 the water in the first instance, for the mere fact that the troughs 

 and fish were inclosed within a building would hardly cause 

 them to suffer in any wa}^; yet the fact of the water running 

 through the air, and perhaps falling even a few inches from the 

 hatching house to the pools may give the conditions necessary 

 for the absorption of sufficient oxygen to support life in the 

 second instance. 



And yet I would not have you think that by the quality of 

 the water I mean water containing sufficient oxygen or air only, 

 for there is also something quite necessary besides this I firmly 

 believe, much less understood, too often little appreciated, but 

 of vital importance to the maintenance of the hatchery. 



Young trout fry, in my opinion, are very sensitive to sudden 

 changes and a change in the quality of the water, for even a short 

 time, may result in a disastrous loss. If the water has once 

 proven all right the greatest care ought to be taken that it re- 

 main so, that no surface water may get into the supply even for 

 n day, that the temperature may not change suddenly by the 

 inflow of melted snow or ice into the reservoir or spring. I be- 

 lieve that nine times out of ten where great losses of young fry 

 have occurred, in a seemingly unaccountable manner, on streams 

 which have been proven suitable for the rearing of this fish, it 

 has been because the quality of the water has suddenly changed, 

 whicli in most cases could have been prevented. If the water has 

 been once proven right take every precaution that it be kept so. 

 Protect your spring or reservoir ])erfectly. A water supply given 

 all possible aeration by artificial means, may not be changed in 

 quality, at least not in such a way as would be the case were it 

 allowed to run exposed to the air and sun over soil and sand. 



