IOWA (Cont. ) 



Began 1909i continuing; $60, 000 (Less 50 percent cash return from sale of 

 fish); Chuck O'Farrell, Leader; reports available. 



Address inquiries to: K. M. Madden, as in No. 16 above. 



20. Lake and Stream Improvement. 



Objectives include lake inlet channeling, fish trap installation in bays and 

 estuaries to limit species use for spawning; experimental stream devices to 

 improve habitat, lake outlet fish screens to prevent rough fish entrance or 

 spawning and lake shore rip-rapping to prevent erosion. 



Statewide; continuing; Bill Tate, Charlie King, Garfield Marker and Chuck 

 O'Farrell, Leaders. 



Address inquiries to: K. M. Madden, as in No. 16 above. 



Iowa State College 



1. Effect of Dredging on Fish and Fish Food Organisms in Shallow Prairie Lakes. 



This study is aimed at evaluation of changes in fish populations and fish food 

 production following the dredging of shallow prairie lakes to improve recrea- 

 tional facilities. Much of the emphasis is on bottom fauna production and upon 

 sampling problems associated with bottom fauna population estimation. Emphasis 

 is also being placed upon the utilization of bottom fauna by various fishes. 



State Conservation Commission cooperating; North Twin, Lizard, and Little 

 Wall Lakes; began May 1951, continuing; $4,500; Kenneth D. Carlander, Leader; 

 reports available. 



Address inquiries to: Dr. Kenneth D. Carlander, Cooperative Fisheries 

 Research Unit, Department of Zoology and Entomology, Iowa State College, 

 Ames Iowa. 



2. Northern Pike Population Studies. 



Norther pike are reared in Ventura Marsh from which they move through a 

 trap to Clear Lake in the fall. Tags are placed on a portion of the young pike to 

 determine the percentage which leaves the marsh and to estimate the population 

 within the marsh. The subsequent yield to anglers will also be studied. 



State Conservation Commission cooperating; Clear Lake; began September 

 1952, continuing; $2,000; Kenneth D. Carlander, Leader; reports available. 



Address inquiries to: Kenneth D. Carlander, as in No. 1 above. 



3. Creel Census on Clear Lake. 



The primary aim is to develop a method whereby the angler's rate of success 

 and the annual yield can be estimated on this lake, despite the many access areas. 

 Emphasis will be placed on measures of the variability of estimates. The data 

 will also be of value in connection with the continuing population studies on Clear 

 Lake. 



State Conservation Commission cooperating; Clear Lake; began June 1952, 

 to close 1955; $3,000; Kenneth D. Carlander, Leader; reports available. 



Address inquiries to: Kenneth D. Carlander, as in No. 1 above. 



4. Population Studies on Walleye Pike. 



This project is part of a long-term investigation of fish population changes in 

 Clear Lake. It includes extensive tagging during spawning run, followed by 

 creel census and experimental gill netting to estimate population, rate of exploi- 

 tation, and mortality rates. Fry plantings have been made in alternate years 

 since 1948 to test value of such propogation. Data are collected on all species to 

 determine population dynamics. 



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