682 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



As a general rule the work of most pisciculturists is done as soon as 

 their young trout or salmon have lost the umbilical bag, and nothing 

 remains to be done but- to place the young fish in suitable locations in 

 brooks and rivers. But the chief work of him who wishes to fatten his 

 fish for the market in inclosed waters only commences at this point. 



There will be a difference in the method of raising trout and saibling. 



According to my experience the simplest and best method for trout is 

 to place the young fish, as soon as the umbilical bag has disappeared, 

 or, better yet, a few days previous, in a small artificially-meandering 

 brook and leave them there till autumn. This brook must be so arranged 

 that the influx of water can be thoroughly regulated. In the beginning 

 the water must flow in only in small quantities and gradually increase 

 till the middle of summer, when the influx can scarcely be strong enough. 

 This artificial brook should, if possible, be arranged in close proximity 

 to some natural brook, but so that it cannot be injured by high water. 

 The well-closing grates at the entrance and exit should be movable, so 

 that coarser grates can be substituted when the fish grow larger and the 

 influx of water is stronger. The most suitable material for such grates 

 is a piece of perforated tin. It is understood that such an artificial 

 brook must have artificial hiding places made of stones, broken pieces 

 of drain-pipe, boards, and suitable aquatic plants. In this brook the 

 trout are left till October or November. If it is of considerable extent 

 and not overcrowded with fish, artificial food is scarcely needed. 



Before new fish are placed in the brook in autumn even the last of 

 the young fish must be removed. In order to do this, it is absolutely 

 necessary to remove even the last drop of water from the brook. It is 

 better that a few of the one-year old trout should perish than that a sin- 

 gle one should remain. The danger that a larger trout will devour the 

 majority of the new fish is of course much greater in an inclosed than 

 in an open brook, as in the latter there are so many more natural hiding- 

 places. 



In raising saibling and bastards of saibling I consider it necessary to 

 keep them during the first year in small, thoroughly inclosed waters, 

 and to feed them with artificial food. All my attempts to raise saibling 

 in the same manner as trout have only yielded negative results. The 

 young saibling which, in those deep waters where it is accustomed to 

 live, has never met with an enemy, has completely forgotten how to 

 fight for its existence. 



It is very interesting to observe how different the mode of life of the 

 trout is from that of the saibling, even from their earliest youth up. 



Young saibling are not at all shy, and when the inclosure is opened 

 they will not fly but come quite close, while trout raised in exactly the 

 same manner will nearly always remain shy, and certainly fly rapidly 

 whenever the inclosure is opened. It is no rare occurrence that young 

 trout, whenever their inclosure is opened, shoot off with such rapidity 

 as to become stunned by bumping against the sides, and even to become 

 fatally injured. 



