320 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



Table 5. — Total annual production of whitefish in pounds in the different districts and areas of the 

 State of Michigan waters of Lake Huron, 1929-1939 



i Year of introduction of deep trap net. 



'Years of heaviest production of whitefish in deep trap nets. 



all-time high in 1931 without the benefit of a really significant contribution from the 

 southern region of the lake (H-5 and H-6) where the increase from 1929 to 1931 

 amounted to only 119,000 pounds. 



In 1932 the first three districts, H-l, H-2, and H-3, after 2 peak years, suffered a 

 severe decline in production. The combined decrease amounted to more than a million 

 pounds. This reduction was compensated to a large extent by further increases 

 in H^, the center of the deep-trap-net fishery in 1932, and by the phenomenal rise in 

 output in H-5, into which district deep trap nets were introduced for the first time. 

 As a result, the total catch for the lake fell only slightly from the 1931 maximum. 



After 2 years of extremely high production the catch of whitefish in H-4 decreased 

 1,701,000 pounds in 1933. The yield in the first four districts combined dropped 

 from 3,342,000 pounds in 1932 to 1,198,000 pounds in 1933, a decrease of 2,144,000 

 pounds. It was hardly to be expected that this large decline in the first four districts 

 could be compensated fully by a rise in production in southern Lake Huron, a region 

 that produced only 136,000 pounds of whitefish in 1929. The increase in catch in 

 southern Lake Huron was nevertheless enormous — 1,163,000 pounds in H-5, 264,000 

 pounds in H-6, and 1,427,000 pounds in the two districts combined. In H-5 the 

 1933 production was 26.6 times the yield in 1929; for H-5 and H-6 combined the 1933 

 catch was 15.7 times that of 1929. The production in the entire lake, however, de- 

 creased in 1933 by 716,000 pounds. 



The output of whitefish increased markedly in H-6 in 1934 (increase of 644,000 

 pounds), but the larger decrease of 892,000 pounds in H-5 led to a drop of 248,000 

 pounds in southern Lake Huron. Increases ranging from an insignificant recovery 

 in H-3 to a sharp rise in H-2 occurred in the first three districts. In H-4, however, 

 the catch dropped 567,000 pounds (from 762,000 pounds in 1933 to 195,000 pounds in 

 1934). The decrease for all six districts was 766,000 pounds. 



