SOME IMPORTANT BAIT FISHES 



its production must be selected more 

 carefully than those used for other 

 bait species (fig. 33). Experience 

 has shown that the following points 

 are important in choosing sucker 

 ponds : 



1. Ponds of moderate fertility usually 

 produce the most suckers. Sterile ponds 

 do not produce enough food for the fish 

 and very fertile ones often produce 

 enouKh algae to cause summer kill. Any 

 pond that becomes pea-soup green should 

 not be stocked with suckers because pro- 

 duction will be very small. If the pond 

 is over 10 feet deep and the algal bloom 

 is moderately heavy, the byproducts of 

 algal decomposition will be dispersed 

 widely enough to make a fair sucker pro- 

 duction possible. 



2. Ponds with large populations of 



chironomid-fly larvae, or blood worms, in 

 the bottom muds will produce good sucker 

 crops more consistently year after year 

 than ponds that do not have an ample 

 supply of these larvae. 



3. The texture of the pond soil is very 

 important. Ponds with loam and sandy- 

 loam soils produce best, peat and peat- 

 loam ponds are average producers, and 

 silt and clay loam ponds are poor. The 

 pond soil is imiwrtant in its effect on 

 water fertility and the production of 

 chironomid-fly larvae. 



4. Ponds with heavy, mosslike growths 

 of filamentous algae over the bottom do 

 not produce good crops of suckers. One 

 Minnesota pond always produced large 

 sucker crops until the filamentous algae 

 got started and covered the entire bot- 

 tom. Since then production has been 

 almost zero. This is possibly because 

 filamentous algae decompose readily and 



FiGUBE 33. — A profitable sucker pond in Minnesota. (Photograph courtesy of the 

 Minnesota Department of Conservation.) 



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