THE WHITEFISH FISHERY OF LAKES HURON AND 



MICHIGAN WITH SPECIAL REFERENCE TO 



THE DEEP-TRAP-NET FISHERY 1 



By John Van Oosten, Ph. D., Ralph Hile, Ph. D., and Fbank W. Jobes, Ph. D., 

 Aquatic Biologists, Division of Fishery Biology, Fish and Wildlife Service 



CONTENTS 



General introduction 



Part I 

 Production of whitefish in Lakes Huron 



and Michigan, 1879-1939 



Lake Huron 



Lake Michigan 



Recent large increase in the produc- 

 tion of whitefish in Great Lakes 



waters 



Paet II 

 Fluctuations in the production and abun- 

 dance of whitefish and in the intensity of 

 the whitefish fishery in the State of Mich- 

 igan waters of Lakes Huron and Michi- 

 gan, 1929-1939 



Introduction 



Methods of analysis 



Statistical districts 



Production 



Units of fishing effort 



Estimation of abundance and fish- 

 ing intensity 



General remarks 



Whitefish fishery of Lake Huron, 1929- 



1939 ... 



Fluctuations in the production of 



whitefish in Lake Huron 



Changes in production in Lake Hu- 

 ron as related to fluctuations in 

 the abundance of whitefish and in 



the intensity of the fishery 



Whitefish fishery of Lake Michigan, 



1929-1939 



Fluctuations in the production of 



whitefish in Lake Michigan 



Changes in production in Lake 

 Michigan as related to fluctua- 

 tions in the abundance of white- 

 fish and in the intensity of the 



fishery 



Part III 

 Bathymetric distribution of whitefish and 

 of certain other species in the shallower 



waters of Lakes Huron and Michigan 



Bathymetric distribution of whitefish 



in Lake Huron 



Northern Lake Huron (Cheboygan 



and Rogers City) 



Alpena-Ossineke grounds 



Saginaw Bay area (Oscoda, East 

 Tawas, and Bay Port) 



Page 

 298 



302 

 302 

 305 



308 



311 

 311 

 311 

 311 

 312 

 313 



314 

 315 



317 



317 



323 

 333 

 334 



338 



348 



348 



348 

 348 



350 



Page 



Bathymetric distribution, etc. — Continued 



Harbor Beach grounds 352 



Bathymetric distribution of whitefish 



in Lake Michigan 352 



Green Bay area (Marinette, Esca- 



naba, and Fairport) 352 



Northeastern Lake Michigan (Man- 

 istique, Epoufette, and Naubin- 



way) 353 



Summary and comparison of the 

 bathymetric distribution of white- 

 fish in Lakes Huron and Michigan, 

 with special reference to the regu- 

 lation of the fishery 357 



Bathymetric distribution of other 



species 359 



Lake trout 359 



Yellow pike 361 



Burbot 363 



White sucker and long-nosed or 

 sturgeon sucker 364 



Part IV 

 Observations on the fishing action of pound 



nets and deep trap nets 365 



Effect of the size of the mesh on the 

 catch of legal- and illegal-sized 



whitefish and lake trout 365 



Destruction of whitefish through gill- 

 ing in the meshes of pound nets and 



deep trap nets 370 



Bloating of live whitefish in pound 



nets and deep trap nets 371 



Dead whitefish in pound nets and 



deep trap nets 372 



Estimates of the probable destruction 

 of illegal-sized whitefish in certain 



localities and years 373 



Shrinkage of the twine in pound nets 



and deep trap nets 375 



Summary 376 



Appendix A. — Sources of the data on pro- 

 duction, 1879-1939 380 



Appendix B. — Detailed statistics on white- 

 fish production in State of Michigan 

 waters of Lakes Huron and Michigan, 



1929-1939 382 



Appendix C. — Investigation of pound nets 

 and deep trap nets in the Wisconsin 



waters of Lake Michigan, 1931 385 



Appendix D. — The whitefish fishery of 

 Lakes Huron and Michigan, 1940-1942 388 



^Approved for publication September 5, 1944. Fishery Bulletin 40. 



297 



