INCREASING THE OUTPUT. 



By W. O. Buck, 

 Neosho, Mo. 



Mother Nature seems to be constantly trying to increase the 

 output of fish and has adopted several details of plan to effect this. 

 Enormous fecundity is perhaps the most important of these, but 

 the concealment of eggs and young and the protection of both by 

 parent fish work to the same end. Apparently these should soon 

 carry the output to infinity, but in fact a limit is soon reached 

 and lakes and streams and even the ocean are but sparsely stocked 

 with fish and are easily depleted. In seeking the explanation of 

 this we find it in the limitation of the food supply. 



When we try to improve upon nature in the supply of young 

 fish, the best we can do is to limp along her path and, since we 

 cannot control fecundity, we must increase the number of breeders 

 and give their offspring more protection and a better supply of 

 food. 



With trout and salmon running wild and handled only at 

 spawning time the problem is comparatively simple, since the 

 fish will be healthy and their numbers can be maintained with 

 moderate effort. When trout must be bred and held in confine- 

 ment, however, several new factors are introduced. The most 

 conspicuous of these is crowding. Although some sorts of fish all 

 through life, and perhaps all sorts at some stage, run together in 

 schools, trout do so only for a short time. Every fish culturist 

 knows that, as soon as they rise and begin to seek food, trout 

 will separate as widely as they can. When food is thrown to them 

 they rush at it from all directions and some are likely to get hurt 

 when they meet. 



Then, too, trout are stream fish and most artificial tanks or 

 ponds fail to provide the best conditions for them. It is also 

 necessary to offer them food which is entirely different from that 

 on which the wild fish subsist. It is small wonder then that 

 under such conditions the fish are not quite normal. Even so, we 

 may and do attain a fair degree of success in propagating them, 

 but when we try to do still better we must get back a little nearer 

 to natural conditions. 



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