CREEK CHUB 



seine, one operator can collect up 

 to 500,000 fry in a day. In collect- 

 ing the fry, the operator carries a 

 floating container tied to his wader 

 strap. In this manner, the small 

 fish are transferred from the hand 

 net to the container without injury. 



As soon as a sufficient number of 

 fry is collected, the fish are trans- 

 ferred in cans to the growing ponds. 

 It is almost impossible to make an 

 accurate count of the number of 

 fry collected other than by hand 

 counting, which wovdd be an endless 

 job. About the only method for 

 estimating numbers of fish would be 

 to concentrate the fry in a container, 

 such as a tub, and remove them 

 with a quart dipper in which the 

 estimated number per dipper had 

 already been determined. Natu- 

 rally, there would be considerable 

 error involved. 



Stocking the groicing ponds.- — 

 The stocking rate of chub fry in 

 growing ponds can be varied con- 

 siderably. In ponds where an op- 

 erator can supply an incoming 

 flow of about 150 gallons of spring 

 water a minute for each acre of 

 Avater, he can stock at the rate of 

 600,000 fry to an acre and obtain 

 a very satisfactory return. If the 

 incoming water supply is limited 

 to about 25 gallons a minute for 

 each acre of water, then it is de- 

 sirable to reduce the stocking rate 

 to about 300,000 fry to an acre of 

 water. In ponds that do not have 

 an incoming supply of water, the 

 operator should not stock heavier 

 than 50,000 fry to an acre of 

 water. 



The records show that in the 

 transfer of fry from the brood 

 ponds to the growing ponds a high 

 survival can be expected. It also 

 seems, according to the informa- 

 tion available, that the rate of sur- 

 vival is in direct proportion to the 

 stocking rate. Ponds stocked at 

 the rate of 50,000 to 200,000 fry per 

 acre of water had about a 90-per- 

 cent survival; those stocked at the 

 rate of 250,000 to 400,000 gave a 

 return of about 80 percent sur- 

 vival; and those ponds in which a 

 nuiximum transfer was made gave 

 a return of about 60 percent. 



Artificial feeding. — During the 

 first 6 weeks of life, development 

 of the chub fry is rapid in ponds 

 having a prevailing water tem- 

 perature of between 70° and 75° 

 F. In this period the fry readily 

 eat fine-grained artificial food. By 

 the end of the 6 weeks, most of 

 these small fish will have reached 

 a length of about 11/4 inches, and 

 there is a marked change in their 

 diet demands : they are no longer 

 interested in the fine food, but seek 

 larger food particles. The oper- 

 ator must now provide a pellet 

 type of food ranging in diameter 

 from i/i6 to i/g inch, or introduce 

 a small forage minnow, such as 

 fathead fry. 



A considerable amount of study 

 has been conducted on diets for 

 the creek chub at commercial 

 hatcheries, and at present the 

 most satisfactory diet mixture con- 

 sists of 4 parts of gray shorts or 

 ground whole wheat, 3 parts of 

 meat scraps or some comparable 



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