Table 18 



Estimates of total hours and total catch, 

 with variances and standard deviations for each two=week period 



YELLOWSTONE HTTER = 1951 



Period 



Nv 



s2(Nh) 



± s(Nh) 



832.2 

 72I4.2 

 9ia;.l 

 1;72.9 



s(N^) 



986.8 

 800.9 

 335.7 

 711.8 

 553.1; 



The results of the two years of creel census on Yellowstone Lake 

 have provided estimates of the total catch for each of the units making 

 up the complex fishing pattern. Limiting factors evident in the 1950 

 census data allowed for considerable refinement in 1951 operations. 

 There are, however, a few factors as mentioned previously which still 

 limit the accuracy of the total estimate, flecognizing these, it is 

 possible for an even more accurate estimate to be made in futirre creel 

 census operations on Yellowstone Lake. 



Estimates of total catch by units for 1950 and 1951 are shown in 

 table 19. There is in most cases an increase in catch for the different 

 units of the fishery. Exceptions arer guideboat fishing at West Thumb 

 dock, lake shore fishing, and Fishing Bridge. The lower catch for guide= 

 boat fishing at West Thumb in 1951 is directly related to the reduction 

 in number of boats operating from this dock9 The lake shore fishing 

 differential may be attributed to the difference in methods of census 

 used in deriving the estimates. Assuming the methods are comparable, 

 the 1951 catch is somewhat lower than that of 1950. The estimates for 

 Fishing Bridge for the two years approximate each other so closely that 

 an assumption of no significant change would seem Justified. The grand 

 totals of catch for the Yellowstone Lake fishery for 1950 and 1951, when 

 considering comparable units, amount to 199,993 in 1950, and 207,860 in 

 I95I5 an increase of 7,867 fish. Including the Yellowstone Hiver catch 

 of 19,729 fish, the 1951 total is 227,589. 



29 



