WHITEFISH FISHERY OF LAKES HURON AND MICHIGAN 



391 



that unusual conditions in the lake which permitted an abnormally high survival of 

 young in one or more years may restore the stock at a much higher rate than the present 

 depleted condition of the population would give reason to expect. 



Not only did the Michigan production of Lake Huron continue its decline after 

 1939, but the Canadian yield snowed a similar trend (table 57), although not to the 

 same disastrous degree. In Lake Huron proper (see p. 304 for its boundaries) the 

 Canadian catch fell to 92,000 pounds in 1940 and increased only 1,000 pounds in 1941. 

 These records are the lowest two for these waters since 1922 and comprise 42 percent 

 of the average catch (219,513 pounds) for the period, 1923-1939. In Georgian Bay (in- 

 cludes the North Channel — see p. 304) the take decreased progressively from 1,275,- 

 000 pounds in 1939 to 833,000 pounds in 1941, the lowest production recorded for this 

 area at least since 1922. This figure represents 58 percent of the average yield (1,427,564 

 pounds) for the years, 1923-1939. In the Michigan waters the 1941 catch equaled only 

 6 percent of the average production (2,052,331 pounds) during the period, 1922-1937, 

 a value considerably less than the comparable Canadian percentages of 42 and 58. 

 The 1939-1941 records of total catch for all waters (United States and Canadian! 

 represent the lowest three ever recorded for the lake. 



Table 57. — Production of whitefish in pounds in Lakes Michigan arid Huron, 1939-1942 



WHITEFISH FISHERY OF LAKE MICHIGAN, 1940-1942 



The production of whitefish in the State of Michigan waters of Lake Michigan, 

 which had declined irregularly from the modern peak of 4,813,000 pounds in 1930, reached 

 an all-time recorded low of 754,000 pounds in 1940 (table 58 — for further data on 

 production see also table 1 of part I, tables 13, 14, 15, and 16 of part II, and 

 appendix B). Although this yield amounted to only 32 percent of the 1929-1939 aver- 

 age, it was relatively much higher than the 1940 catch in Lake Huron (9 percent of 

 the 1929-1939 mean — table 52). The take of whitefish in Lake Michigan improved sub- 

 stantially in 1941 (896,000 pounds; 38 percent) and 1942 (1,061,000 pounds; 46 per- 

 cent). The 1940-1942 trend of production was consistently upward in northern and 

 northeastern Lake Michigan (M-2, M-3. and M-4) and in the Grand Haven-Muskegon 

 district (M-7), but was consistently downward in Green Bay (M-l) or irregular in the 

 remaining districts (M-5, M-6, and M-8). 



In all three years M-3 contributed considerably more than half of the total pro- 

 duction (63.8, 58.4, and 67.5 percent in 1940, 1941, and 1942, respectively). The Green 

 Bay district (M-l) ranked second each year but contributed a constantly decreasing 

 percentage of the total (16.3, 12.9, and 8.7 percent). Third position was held by M-5 

 in 1940 and 1941 (11.5 and 10.0 percent) and by M^ in 1942 (6.7 percent). The per- 

 centage of the total yield produced in the districts that ranked lower than third ranged 

 from 7.5 percent in M^4 in 1941 to 0.1 percent in M-7 in 1940. It may be noted that 

 the percentages of total production in the various districts in 1940-1942 resembled the 

 corresponding figures for 1891-1908 much more closelv than they did those for 1929- 

 1939. 



The abundance percentages, records of catch per unit of effort, and figures on 

 fishing intensity (tables 59, 60, 61, and 62 — see tables 17, 19, 20, and 21 of the main 

 body of this paper) show that but for a low level of fishing intensity, production would 

 have been much higher in 1940-1942, particularly in the last two years of the period. 

 The abundance of whitefish which had dropped to an extremely low level in 1940 (23 



