298 FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



GENERAL INTRODUCTION 



The great economic value of the whitefish {Coregonus clupeaformis) and the wide- 

 spread demand for it by the general public combine to make conservation of this species 

 a matter of primary importance. Accordingly, conservation officials were gravely dis- 

 turbed by the numerous reports and complaints of commercial fishermen in 1928, 1929, 

 and 1930 concerning the operation of a new type of gear — the deep trap net — in the 

 waters of Lake Huron off Alpena, Mich. These nets, the complainants contended, 

 took whitefish literally by the tons, threatening the immediate extinction of the com- 

 mercial stock. They held further that the deep trap net not only took legal-sized white- 

 fish in unreasonable quantities but that it was also highly destructive to immature fish. 



Gill-net fishermen stated that they were forced to suspend operations in areas in 

 which deep trap nets were fished because of the thousands of rotting, undersized white- 

 fish that drifted into their nets. These fish, they believed, had been destroyed in the 

 deep-trap-net fishery. They charged specifically that young whitefish were killed by 

 confinement in deep trap nets, by gilling in the trap-net meshes, by the rapid change 

 of pressure when the nets were lifted, and by excessive and rough handling in the sort- 

 ing of the catch. They charged further that deep-trap-net fishermen habitually 

 dumped the dead, undersized whitefish overboard, and thus ruined the best whitefish 

 grounds by polluting the bottom and driving away the fish. 



Operators of both gill nets and pound nets objected to allegedly unfair tactics of 

 deep-trap-net fishermen. Gill-netters stated that deep-trap-netters had usurped the 

 traditional gill-net grounds and even had deliberately set deep trap nets across 

 strings of gill nets. Pound-netters asserted that deep trap nets were set offshore 

 in such positions as to block the passage of whitefish to the inshore pound-net grounds. 



Both groups of fishermen complained that the high production by deep trap nets 

 had glutted the market and depressed prices, making operations with other gears un- 

 profitable. 



The extent to which the many accusations leveled against deep trap nets and their 

 operators were just could not be determined without extensive field observations. Pre- 

 liminary inquiries, nevertheless, revealed that the deep trap net constituted an un- 

 deniably serious threat to the whitefish fishery. It was in recognition of this menace 

 that the Michigan Department of Conservation and the United States Bureau of 

 Fisheries (now the Fish and Wildlife Service) agreed to carry out cooperatively a 

 program of field observation, in order first, to determine the effects of the deep trap net 

 on the whitefish fishery, and second, to obtain information on which to base recom- 

 mendations for sound regulation of the gear. 



By 1931, the first year of the cooperative field investigations, the deep-trap-net 

 fishery had expanded so rapidly that in a number of localities the net had become the 

 dominant gear for the catching of whitefish. These nets were then being fished ex- 

 tensively in the State of Michigan waters of Lake Huron as far south as the "Middle 

 Grounds" off the mouth of Saginaw Bay and had spread also into Lake Michigan where 

 they were used in Green Bay and in northern Lake Michigan, out of Manistique and 

 especially out of ports of the north channel area (region north of the Beaver Islands) . 

 In 1931 deep trap nets were fished also in the waters of Door County, Wisconsin. (For 

 a condensed report of the brief survey of these waters in 1931 consult appendix C.) 



The Michigan Department of Conservation's Patrol Boat No. 1 was placed at the 

 service of the United States Bureau of Fisheries investigators from July 22 to 27, 1931, 

 when a general survey of the deep-trap-net grounds of northern Lake Michigan and of 

 Lake Huron was made. For the conduct of the later routine field observations, the 

 Department of Conservation assigned one field assistant and paid the operating expenses 

 of one automobile from August 1 to October 21, 1931, and during the month of May 1932. 

 Beginning June 1, 1932, and extending into October, when the field work was discon- 

 tinued, the Michigan Department of Conservation furnished three field assistants and 

 paid the operating expenses of two automobiles. This increase of the staff made it 

 possible to conduct the investigation simultaneously on both northern Lake Michigan 

 and Lake Huron. The fishermen were practically all willing to cooperate by allowing 



