ment measure to improve fishing success would merely give anglers 

 and fisheries managers a false sense of security. The true cause of 

 the decline would not be found and would not be corrected. 



Contribution Of Hatchery Trout Study 



A four-year study was concluded this biennium on the lower 

 25 miles of Rock Creek below Red Lodge, Montana in district num- 

 ber 3. This section of Rock Creek is predominantly a brown trout 

 stream. The study was designed to measure the contribution of 

 hatchery reared trout to the total catch. 



Approximately 20,000 yearling marked rainbow trout, averaging 

 5.4 inches in length, were planted each year prior to the opening 

 of the fishing seasons in the years 1950, 1951, and 1952. These plants 

 contributed 4 to 5 percent of the creel in the year planted and 7 to 8 

 percent of the creel the year after liberation. 



In 1953 approximately 9,000 marked rainbows, averaging 7 inches 

 in length, were planted after the start of the fishing season. These 

 fish were liberated at points of access throughout the fishing season. 

 This plant contributed 20 percent of the total fish caught during the 

 1953 season. 



This study demonstrates the benefits that can be gained from 

 following wise fish stocking procedures and demonstrates as well the 

 absolute waste of money that does result from negligence in fish 

 stocking. 



Water Analysis 



Brush Lake in Sheridan County, Montana, (district number 5) 

 has a surface area of 200 acres and a depth of 57 feet. Fish have 

 been planted at intervals in past years in a considerable quantity. No 

 catch of fish has ever been reported. It is a beautiful lake and is 

 located in a country that needs such waters for recreational fishing. 



But before further plants of fish were made, the district biologist 

 examined the water. Water analysis showed the lake to be highly 

 saline. The most significant fact discovered, however, was the lake 

 was almost devoid of dissolved oxygen. Fish could not live in water 

 with only 0.5 p. p.m. dissolved oxygen, therefore further efforts at 

 stocking the lake will be stopped. These fish may now be used in 

 other waters where desirable results will be obtained. 



Rehabilitated Lakes 



During this biennium three lakes were rehabilitated. Savage Lake 

 near Troy which was populated with sunfish and carp, Birkland's 

 Reservoir near Fort Benton which was populated with bullheads, 

 and Stewart Lake near Philipsburg which was populated with carp 

 and yellow perch. 



All will be planted with trout when they become non-toxic to 

 fish. Special mention should be given to the Flint Creek Sportsmen's 



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