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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



The range of rank was the greater in the more recent period in each district except 

 H-3, a region in which the whitefish fishery was unimportant after 1932. The great- 

 est increase in range occurred in H-5 which held every position from first to sixth 

 although this area had ranked sixth 17 times (fifth in the remaining year) in the 

 period, 1891-1908, and had not yielded more than 7,500 pounds in any one of the 18 

 years. 



It should be noted further that with only one exception (the rank of 5) each of the 

 rankings from 1 to 6 occurred in more districts in 1930-1939 than in 1891-1908. For 

 example, first position was held in four districts (all but H-2 and H-3) in the more 

 recent period as compared with only two (H-l and H^4) in the earlier years, second 

 rank was held by four districts in 1930-1939 as compared with three in 1891-1908,***. 



The actual figures of catch of tables 5 and 6 support the observations based on 

 the rankings, for the yields of the individual districts were in general far less variable 

 in the early than in the recent period. 



Table 6. — Production of whitefish in pounds in Lake Huron according to statistical districts, 1891-190S 



The records of yield for the years, 1891-1908, indicate also that the percentages 

 of the total catch of whitefish in the different districts were approximately normal in 

 1929, the only recent year (with data for each district separately) in which the sta- 

 tistics were not seriously distorted by the deep-trap-net fishery. It is true, the per- 

 centage distribution of the catch of whitefish in Lake Huron in 1929 (table 5) differed 

 somewhat from that for the average for 1891-1908. It will be noticed, for example, 

 that in 1929 the greatest production (39.2 percent) was from H^4 with H-l in second 

 position (25.8 percent) whereas in 1891-1908 the greatest average yield came from 

 H-l (56.6 percent) with H-i in second position (24.9 percent). Among the remaining 

 districts the percentages were higher in 1929 in H-2 (in part because of the catch in 

 deep trap nets), H-5, and H-6, and possibly lower in H-3, 23 but the rankings of the 

 districts were the same. 



The differences in the values of these percentages are not large enough, however, 

 to warrant the conclusion that the relative capacities of the various districts for the 

 production of whitefish in 1929 were changed greatly from those of 1891-1908. Although 

 the high percentage of the total yield of whitefish in H-4 in 1929 is in disagreement 



23 The division of the statistics for the earlier years was based on the location of the home port and not necessarily on the grounds actually fished. 

 It is known that, in more recent years at least, some fishermen from Au Sable-Oscoda (H-3) have operated with gill nets in H-4 on the "Middle 

 Grounds" off Saginaw Bay. In 1929 and 1930 these fishermen accounted for about 14 percent of the total whitefish catch of H-4. If this same per- 

 centage held for the earlier years the average production in H-3 and H-4 should have been 32,392 pounds and 281,947 pounds, respectively, instead 

 of 71,865 pounds and 242,474 pounds as recorded in table 6: the percentages should have been 3.3 and 29.0 instead of 7.4 and 24.9. There is no 

 reason to believe that the data for other districts were affected significantly by the division of the catch according to port. 



