FOREST, LAKE, AND RIVER 



stream with the current. They are partially de- 

 voured by cunning minnows and other fish, now 

 and then, who are lurking in the vicinity unseen 

 by the male trout, who is deeply absorbed in the 

 duties to which he is impelled by the spawning 

 instinct. 



Probably not more than five per cent of the ova 

 dropped on natural spawning beds ever mature, 

 while of those raised by the improved methods of 

 the fishculturist, fully seventy-five to ninety per 

 cent come to maturity in the hatching ponds. 



Unfortunately those raised by the artificial pro- 

 cess are generally placed, when less in size than 

 fingerlings, in streams abounding with their natural 

 enemies, and but a small percentage of these inno- 

 cents become yearlings, at which time they are 

 measurably able to take care of themselves. 



The number of eggs yielded by an adult trout 

 depends upon its size and age. Yearlings usually 

 produce one hundred and fifty to two hundred and 

 fifty ; two years increase the number to three hun- 

 dred and fifty to five hundred, and older fish five 

 hundred to twenty-five hundred. 



The general form of the brook trout varies very 

 much. Sometimes it is long for its depth and 

 sometimes short, but the average depth is about 

 one-fourth, or one-fifth of the length of its body. 



lOO 



