and over, which were collected and released each 

 year were: 1955, 75; 1956, 69; 1957, 6; 1961, 23 and 

 1962, 23. This information shows that while the initial 

 effect of severe stream damage partially diminishes 

 with time, the damaged section will have fewer trout 

 for a long time and sometimes indefinately. An 

 attempt will be made to improve the existing habitat 

 in this section by placing boulders in the cleared 

 channel. The section will be sampled periodically 

 in the future. 



The Rock Creek creel census study has continued 

 since 1958. This research project is designed to ob- 

 tain angling pressure and harvest information from 

 Rock Creek as a means of evaluating the use of 

 catchable-sized fish for stream planting. The basic 

 plan for this study was to plant Rock Creek annually 

 with 30,000 hatchery-reared rainbow trout for the 

 initial three years of the study, then to cease planting 

 for several years after which angling pressure and 

 harvest information for each period would be com- 

 pared. At the end of these two phases, data will be 

 analyzed to determine if Rock Creek should be 

 planted. If planting is necessary, the study will con- 

 tinue in an attempt to establish the optimum planting 

 rate. 



Information to date has shown that approximately 

 15,000 fisherman trips were made in Rock Creek each 

 year during the 1958-60 period. The harvest of game 

 fish during this period was approximately 50,000 

 game fish each year. Planted fish comprised 23.0 

 to 26.4 per cent of the yearly harvest of fish from 

 Rock Creek. The return to the creel of planted fish 

 ranged from 34.3 to 40.1 per cent in the year they 

 were planted. An approximate one to four per cent 

 were taken following the year of plant. 



Final estimates have not been completed for the 

 1961 angling season. Preliminary estimates indicate 

 that there was a reduction in both harvest and pres- 

 sure during the first year without planting. This was 

 as anticipated. However, the rate of angling success 

 (fish caught per hour) remained at a comparable 

 level to that of the initial three years. 



In 1960, each angler's fishing license number 

 was recorded in addition to standard census data. 

 This procedure was adopted as a means of de- 

 termining the distribution among anglers of the total 

 number of fish checked through the check stations. 

 Census coverage was approximately 50 per cent. 

 This investigation revealed that the most successful 

 five per cent of both resident and non-resident license 

 holders interviewed, made 18 per cent of the total 

 number of fishing trips to Rock Creek and caught 33 

 per cent of the fish caught. In adding the next five 



per cent of most successful anglers, a total of 10 per 

 cent of the anglers checked made 27 per cent of the 

 fishing trips and caught 50 per cent of the fish. At 

 the 25 per cent level of most successful anglers, 45 

 per cent of the trips were made, and they caught 77 

 per cent of the total number of fish caught. Although 

 the stream had been planted at a relatively heavy 

 rate, 33 per cent of the anglers interviewed caught 

 no fish. 



SOUTHWEST FISHERIES DISTRICT 



Mountain lakes were emphasized in the survey 

 work during this biennium. Forty -one lakes in the 

 Gallatin-Madison area were surveyed. Information on 

 physical and biological characteristics was obtained 

 so the fishery potential of these waters and the 

 management measures could be determined. 



A fish population study of Dailey Lake was made 

 during 1960 and 1961. Creel census was conducted 

 during the regular fishing seasons of both years. 

 Fishermen harvested approximately thirty pounds of 

 rainbow trout per acre and approximately ten 

 pounds of yellow perch per acre each year. The 

 estimated annual harvest was about 10,000 rainbow 

 as compared to the annual plant of 20,000 catchable 

 rainbows. Natural mortality apparently takes about 



U»o of a helicopter has greatly glmpUded transportation lor 

 lain lake surveys. 



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