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artificial ponds. A natural pond may not produce so 

 many minnows per acre as the artificial pond, but where 

 the cost of purchase or rental is reasonable, such a 

 pond can be very profitable. 



Natural ponds available for the production of 

 minnows vary greatly in size and shape, but the small, 

 shallow pond can be expected to produce a larger number 

 of fish per acre than the large, deep pond. This is 

 due to the availability of a greater area of productive 

 bottom for the volume of water, and to the more thorough 

 harvesting of the fish. The ideal pond ranges from 

 1/4 to 1 acre in size. Most natural ponds are dependent 

 on surface run-off for water supply, and many go dry 

 during the summer. Before a pond can be used for pro- 

 ducing minnows, the bait dealer must make certain that 

 the pond maintains a depth of water to sustain fish 

 life throughout the growing season. 



Natural ponds vary greatly in fertility. Ponds 

 located in ricii farmland are usually productive; ponds 

 on poor, rocky soils are infertile unless the run-off 

 includes a large quantity of organic pollution. The 

 natural fertility of the pond is largely determined by 

 the hardness of the water. Medium hard to hard water 

 will produce more pounds of fish per acre than soft 

 water. The amount of bloom and vegetation in the pond 

 is a good indication of fertility: the richer ponds 

 have a greener bloom. 



Seining conditions in natural ponds must be con- 

 sidered before a pond is selected. There is no profit 

 in raising minnows that cannot be harvested completely. 

 Ponds with bog shores, steep banks, or soft bottoms 

 should be avoided unless there is at least one firm- 

 bottomed beach that slopes gradually enough for good 

 seine landings. A pond full of trees and brush is 

 impractical to operate. 



In winter when these shallow (4- to 5-feet deep) 

 ponds are covered with ice and snow, the production of 

 oxygen by the plants in the water will drop so low that 

 the available supply will be exhausted rapidly and the 

 fish will smother. Throughout most of the Lake States 

 a natural pond 15 feet deep will often winter minnows 

 but they may freeze-out during unusually severe weather. 

 When a good current of water can be maintained through- 

 out the winter, the pond need not be more than 6 feet 

 deep. 



Sometimes the bait dealer has no choice but to hold 

 minnows in shallow ponds. During open winters with 

 little snow, this is possible because the ice, whether 



