IOWA (Cont.) 



13. Lake and Stream Improvement. 



The objectives of this project include inlet channeling in lakes, installation of 

 fish traps in bays and estuaries to control use of spawning areas for desir- 

 able species, experin^ental lake and stream devices to improve the habitat 

 for game fishes, and rip-rapping of lake shores to prevent serious erosion. 



Statewide; continuing. 



Address correspondence to: K. M. Madden, Supt. of Fisheries, East 7th and 

 Court Sts. , Des Moines, Iowa. 



14. Rough Fish Studies. 



This project involves a general collection of data on carp, buffalo, sheepshead 

 and gizzard shad. The primary portion of this study has concerned food 

 habits, but data have also been collected on ecology, age and growth, repro- 

 duction, sexual maturity, number of eggs per fish, and condition factors in 

 an over -all effort to determine the interrelations existing between rough fish 

 and their environment and between rough fish and game fish. 



The natural lakes of northwest Iowa; began January 1946, continuing; $1,000; 



Tom Moen, Project Leader; data in quarterly biology reports. 

 Address correspondence to: E. B. Speaker, Supt. of Biology, East 7th and 



Court Sts. , Des Moines, Iowa. 



15. Rough Fish Removal. 



Principal objective of this project is to reduce the population of rough fish in 

 state-owned waters inan effort to increase game fish populations. This in- 

 cludes some work on streams, however, the principal en-iphasis is placed 

 on the natural and artificial lakes. In some instances, attempts are made 

 to reduce stunted populations of crappie and other pan fish. An average of 

 one million pounds of rough fish are removed from the inland lakes of the 

 State annually. 



Statewide; began 1909, continuing; $60,00U (less 75 percent cash return from tne 

 sale of fish), reports included in the biennium reports of the State Conserva- 

 tion Commission. 



Address correspondence to: K. M. Madden, Supt. of Fisheries, East 7th and 

 Court Sts. , Des Moines, Iowa. 



16. Lake Dredging. 



The purpose is to desilt the shallow natural lakes where silt deposits have accu- 

 mulated to the extent that they pose a hazard to recreation, fish life, and 

 public use. Areas deepened by hydraulic dredging average from 70 to 160 

 surface-acres in each lake. In addition to the 10 lakes completed, two are in 

 the process of being deepened at this time. 



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