whether it be lake or stream, can support only a certain poundage of 

 fish — the same as a range can support only so many head of cattle. 

 Where the growth rate is found to be low and the fishes' condition poor, 

 stocking trout will be a waste of fish. When such lakes and streams 

 are found, improvement efforts will be made to increase their pro- 

 ductivity. 



To supplement this productivity data, creel census is needed. Creel 

 census measures production, and it is more valuable than any single 

 item of data. A program of creel census was begun and will be con- 

 tinued indefinitely. This catch data is gathered by co-operation from 

 three sources: (1) Game wardens in the course of their regular duties 

 record the fishermen's catch data. (2) Dude ranches, resorts, boathouses, 

 and guides are contacted and asked to keep records for those fishing 

 under their supervision. (3) "Fishermen's Log Books" are distributed 

 to co-operative sportsmen that they might have a convenient place to 

 record their individual catches. 



The data desired is the water fished, the date, the number, kind 

 average size fish caught and the hours spent fishing. This will be 

 analyzed in many ways, but chiefly to discover the percentage of each 

 species of fish taken to aid in knowing where work should be done and 

 will provide a measure of the success of initiated improvement measures. 



To date eighteen ranches, resorts, boathouses and guides are co- 

 operating, and three hundred fifty "Fishermen's Logs" have been dis- 

 tributed. At the opening of the fishing season, all the game wardens 

 will record the catch data. Whether the general public will contribute 

 to the creel census in a manner making the data usable remains to 

 be seen. 



In anticipation of an investigation of Fort Peck Reservoir to deter- 

 mine population levels, to determine the possible need for rough-fish 

 control, and to study the problems of optimum fish utilization, plans 

 were laid and much equipment acquired. This project is to be a co- 

 operative one with the department, the Missouri River Basin Studies 

 of the Fish and Wildlife Service, and the Army Engineers. 



One of the greatest detriments to Montana's fishing has been the 

 unwise introduction of various species of fish. Some of these, like 

 the introduction of sunfish into Lake Mary Ronan, were done deliber- 

 ately by individuals. A large majority of these introductions, however, 

 such as the chub in Hebgen Lake, probably were made by using minnows 

 to fish. Where an overwhelming poundage of the fish in a lake or stream 

 are rough fish, additional stocking of trout may aid but little. This 

 condition should be rectified before further stocking will produce satis- 

 factory results. In certain cases, stocking of large fish may control the 

 rough fish. In other cases, this will not work. Game fish other than 

 trout may also fail under many conditions to produce the optimum in 

 recreational value in the face of concentrations of rough fish. 



A crew of two men will begin work in the spring of 1948 on Hebgen 

 Lake. Besides furthering work of tag recovery and gathering data for 

 productivity studies, they will spend much time considering the trout- 

 chub relationship and determining methods of chub control. 



Complete eradication of rough fish in waters where this is possible 

 is most desirable. By doing so, it is possible to restore lakes, ruined 

 by the introduction of undesirable species, to their former ability as 

 trout producers. In accordance with this work, complete eradication of 

 fish will be made in 1948 in Spoon Lake near Whitefish and Savage 

 Lake near Troy. 



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