114 American Fisheries Society 



tend to leave the water more or less roily. For this rea- 

 son the nests should be set long enough before spawning 

 time for the water to become perfectly clear before 

 spawning begins. 



High temperature in the water supply is desirable in 

 case of a sudden drop in the air temperature to the ex- 

 tent that it would lower the water temperature to the 

 point where the adults may abandon the nests. If a 

 large supply of water with a high temperature is turned 

 into the spawning pond, its is possible to keep the tem- 

 perature of the pond above the danger point. 



Brood Stock 



Good sized adults are preferred for breeders, as the 

 size of the schools of fry will be in proportion to the 

 size of the adults. Other things being equal, success 

 will be marked in proportion to the size of the adults. 

 All adults under one pound should be discarded. 



If native stock is to be collected for breeders, it is de- 

 sirable that it be secured in the fall. The fish then be- 

 come accustomed to their new environment before spawn- 

 ing time and will produce more spawn than if collected 

 in the spring. 



A good brood stock can be obtained by rearing young 

 bass to adults on artificial food. With a brood stock 

 thus reared, the food problem is solved and the breeders 

 will always be in good shape at spawning time, which is 

 a very important requisite for a good yield of fry. When 

 young bass are to be reared for breeders, they may be 

 taken from the pond when one or two inches long and 

 placed in troughs or tanks where they can be taught to 

 take artificial food. When they are about three inches 

 long and are taking food well, they should be transferred 

 to a small pond in order that they may have more range. 



These young bass will spawn when two years old, the 

 average number of fry for each female being about five 

 or six hundred the first year, the number increasing as 

 the fish grow older and larger. 



