36 



and 450 pounds of dried sheep manure. An unfertilized 

 1-acre pond was stocked with 200 golden shiners. This 

 pond received some fertilization from pasture drainage. 

 The fertilized pond had a total yield of 421 pounds of 

 fish (85.6 pounds per acre), while the 1-acre pond 

 produced 245 pounds. This indicates that the 5-acre 

 pond was greatly understocked and that the 350 adult 

 fish had produced all the young possible. The average 

 number of fish produced by each female was 650. As 

 the females in the 1-acre pond also averaged 650 young, 

 it is apparent that the extra space and the excess of 

 food in the 5-acre pond had no effect on the total 

 number of fish produced. The excess of food showed in 

 the size of the fish at time of harvest. In the ferti-^ 

 lized pond 46 percent of the population averaged 25 to 

 3i inches total length; in the unfertilized pond only 

 16 percent of the fish reached those sizes. Pish in 

 the fertile pond grew to 3i inches in 11 weeks, but 

 fish in the poorer pond required 16 weeks. 



Table 5. — Bait-fish production by Michigan Institute for Fisheries Research, 1946 



Time of Harvest 



Minnows are harvested only when they have reached 

 suitable size for bait. With some fast-growing species 

 such as suckers and golden shiners, a few may be removed 

 late in their first summer and others may remain in the 

 ponds until the second summer. Seining in the fall 

 when the weather is cool, is easier and offers less 

 injury to delicate minnows, although demand is less at 

 that time and holding tanks are necessary to keep the 

 fish xintil the winter fishing season. 



The Institute for Fisheries Research at Ann Arbor 

 (Mich.) has developed a technique for harvesting golden 

 shiners during warm weather. The fish are caught in a 

 drop net with cheesecloth webbing and are handled with 

 a scap that is also hung with cheesecloth. The fish 

 must be hardened in cold water for 24 hours before they 

 can be transported (p.72). 



