51 



115-clay growing season; in another stocked at the rate 

 of 32,000 per acre, 11,000 salable fish were produced 

 in a comparable period. 



Those figures seem low when compared with the 

 output of ponds for which the stocking rate is not 

 available. In Ohio, approximately 11,000 creek chubs, 

 averaging about 3.5 inches in length, were produced in 

 a 1/12-acre pond, and about 9,000 in a 1/7-acre pond. 

 This would represent production at the rate of 135,000 

 and 63,000 fish per acre, respectively. In both ponds 

 the fish were given artificial foods. In Michigan, a 

 1.8-acre pond produced 58,000 chubs, a yield of about 

 32,000 per acre. Prom general analysis of the data on 

 hand, it would seem that a pond could be expected to 

 produce from 100,000 to 200,000 salable fish per acre 

 per year if artificial feeding was practiced, or by 

 fertilization if an equivalent amount of available food 

 could be provided by this method. In ponds (not ferti- 

 lized) where the fish had to rely on natural food for 

 growth, it is doubtful that more than 50,000 could be 

 expected per acre of water. When stocking rearingponds 

 in anticipation of a certain production, consideration 

 should be given to normal mortality (25 to 50 percent). 

 A possible but yet untested way in which to in- 

 crease creek-chub production is by the use of raceway 

 ponds similar to those used in trout culture. These 

 long, narrow ponds that have a continual flow of water 

 passing through could be stocked heavily with chub fry 

 early in the year; feeding could be started at once. 

 As in trout culture, the daily portion of food would 

 have to be increased, probably each week, to compensate 

 for the increased demand of the growing fish. Further 

 to increase production, about once a month or oftener 

 the chubs should be graded according to size groups and 

 the larger ones sold (if of salable size) or removed 

 to some other pond. By removing the larger fish, the 

 competition for food will be reduced and the small chub 

 will have a better chance to obtain his share. It is 

 believed that there would be several advantages in 

 raising creek chubs in this manner: first, less area 

 would beneeded for pond construction; second, the fish 

 could be sorted and harvested easily; and third, there 

 would be less food wastage. The probable disadvantages 

 would be the requirement of more water than would 

 normally be needed for rearing ponds, and a higher 

 mortality from disease as a result of crowding. 



