6 Food of Fishes of Winona Lake 



raised a walleyed pike from the green egg to a length of 17 inches in 7 

 months by supplying it with an excess of food. This was the maximum, 

 many others were 10 inches or over. 



As I have suggested before, many classes of food are available for short 

 periods only. For instance there is a little insect larva (the larva of the fly 

 Chironomus) that is found at the bottom of most of our lakes. In Winona 

 Lake it produces about 70 pounds dry weight of fish food per acre per year. 

 However, most of them live below the feeding level of our fishes. When they 

 wiggle to the surface to transform they become available and are eaten in 

 large numbers. But this period lasts only for about two or three weeks in 

 autumn. In order to keep fish feeding conditions up to maximum effi- 

 ciency other forms should be available in like amounts during the other six 

 months of the feeding season. In the present state of our knowledge this 

 would be a very difficult thing to do. It seems that a more practical way 

 of using this supply of fish food would be to introduce the Cisco. This fish 

 feeds at the deeper levels during the summer. 



The hatching of fish and raising them to the eyed, fry, or fingerling stage 

 has been developed to a very efficient level. The methods of transporting 

 them to the place selected for planting are such that the loss is negligible. 

 If the production and planting of young fish were the only things needed to 

 increase the yield of legal sized fish in our streams, then the amount of fish 

 in our streams and lakes would be limited only by the output of our hatcheries 

 and that in turn only by the amount of money that we cared to expend on 

 them. 



We have a law that protects our game fish while on the breeding ground. 

 The closed season should extend to July first as the bass are not all off the 

 nest in the lake region before that time but the law is a good beginning. 

 Many of our citizens contribute time and money to fish hatching - . 



Yet in spite of all of this work there remains this limiting factor of 

 fish foods that determines the number and size of fish that we can produce 

 in our waters. Often the damage done a stream or lake through drainage 

 or pollution has not killed the fish directly but has made it impossible to 

 grow much fish food and thus the fishes have been reduced indirectly. 



An illustration may make this point clear. The Tippecanoe river was 

 formerly a black bass stream for its entire length. In its upper course the 

 bottom was a luxuriant meadow of water plants. This was filled with fish 

 foods culminating in the minnows. Dredged ditches made tributary to the 

 Tippecanoe have covered this natural bottom with sand for some miles below 

 their mouths. This would not kill the bass directly, but there is little to 

 support a fish fauna and consequently few if any fish. 



When a lake is lowered few if any fish are killed directly, but the mar- 

 ginal plants which support and protect the organisms that form the basic 

 elements in some of the food chains are destroyed. 



But I have said enough to indicate the importance of the problems con- 

 nected with fish food. Some of them are extremely difficult and their solu- 

 tion will take much time and energy. But they must be solved if we are to 

 increase not only the number of fish planted but the number of fish caught. 

 Mr. DeRyke's paper is a partial answer to one of these basic questions, 

 "What do fish eat?" 



