BEARING YOUNG TROUT 161 



ing-house to the ponds is made, that the nninber 

 has been much reduced. I have known the loss 

 to be half during the first summer of an estab- 

 lishment. 



One method, usually safe, of reducing the 

 death-rate during the advanced-fry and finger- 

 ling stages is to furnish plenty of shade. At 

 one of the stations in Pennsylvania the annual 

 death-rate was from 50 to 75 per cent., until the 

 nursery-ponds were completely covered, be- 

 tween March and October, whereupon the 

 death-rate fell from 10 to 15 per cent. 



Automatic Feeders. — ^Rapidity of growth, 

 which is important when rearing for the mar- 

 ket, can best be stimulated during the first six 

 or eight months after the sac is absorbed by 

 the use of one of the forms of automatic feed- 

 ing apparatus. It is then possible for one man 

 to care easily for almost any number of ponds 

 holding from 5,000 to 10,000 fish each. Young 

 trout should be given all the food they can con- 

 sume, but no more, since more will be a waste, 

 and will foul the ponds. The reservoir of the 

 feeder should be replenished at regular inter- 

 vals with an amount that will become exhausted 



