89 



preferences of a fish usually vary with its age. The 

 young can swallow only small organisms and therefore 

 feed mostly on plankton. Adults require larger and 

 more substantial food. For maximum production in ponds, 

 minnows should be provided with the foods most suited 

 to their needs and their ages. Choice of pond and 

 fertilization can greatly affect the type and availa- 

 bility of food. Table 11 presents a summary of the 

 percentages of food items used by certain bait species, 

 as examined in various studies. 



Water temperatures have a direct effect on the 

 amount of food eaten by a fish. In cold-water ponds 

 the consumption of food is low and growth of the minnows 

 is slow. Also, when the water becom.es excessively hot, 

 food consumption again declines and growth becomes slow. 



Spawning requirements, like feeding habits, are 

 different for different minnow s pecies. Some require 

 flowing waters; others do not. Some lay their eggs on 

 vegetation; some lay their eggs on open gravel shoals 

 or under debris. Some have extended spawning seasons 

 and others have short ones. Adequate facilities for 

 spawning are necessities in good pond management. 

 Table 12 presents a summary of information regarding 

 the breeding of certain bait species. 



To comply with natural habitat requirements is 

 important for some species. Those normally living in 

 bog streams or swift currents might not be readily 

 adapted for life in ponds or holding tanks. In general, 

 however, most stream or lake minnows can be reared in 

 ponds and with proper feeding may grow at faster rates 

 than in their natural environment. 



The name "minnow" is commonly but erroneously 

 applied to small fishes of all species. The true 

 minnows, however, are members of one family of fresh- 

 water fishes (Cyprinidae) and have definite character- 

 istics that separate them from other families. Most 

 minnows are small but some like the carp (an introduced 

 minnow) and the western "white salmon" attain a weight 

 o f 40 to 80 pounds. Young specimens of game and food 

 fishes such as perch minnows and pike minnows, which 

 should be called fry or fingerlings, are often improp- 

 erly called minnows. Most bait fishes areminnows, but 

 some important species like the mud minnow and the 

 sucker belong to other families. 



