PROGRESS IN BIOLOGICAL INQUIRIES, 1931 ' 



By Elmer Higgins, Chief, Division of Scientific Inquiry 

 [With the collaboration of investigators] 



CONTENTS 



Paga 



Introduction 442 



North and Middle Atlantic fishery investigations 447 



Haddock 448 



Mackerel 451 



Cod 454 



Winter flounder 455 



Shore fishes of the Middle Atlantic States 456 



Oceanographic studies 460 



Experimental rearing of fish larvse 461 



Chesapeake Bay investigations 462 



South Atlantic and Gulf fisheries investigations 462 



Shrimp 463 



Great Lakes fishery investigations 465 



Chub-net studies in Lake Michigan 465 



Deep trap nets of Lakes Huron and Michigan 467 



Studies in Lake Erie 467 



Lake Champlain 469 



Wisconsin lake studies 469 



Studies of fish growth 469 



Cooperative limnological investigations 470 



Pacific coast and Alaska fishery investigations 474 



Alaska red salmon 474 



Alaska pink-salmon investigations 478 



Statistics of the Alaska salmon fisheries 479 



Alaska herring 479 



Puget Sound sockeye salmon 481 



Rogue River steelhead tagging 481 



Conservation of fish by means of screens and ladders 482 



Mechanical fish screens 482 



Electric fish screens 484 



Fish ladders 489 



New and proposed power projects 490 



Salmonidffi of New England 492 



Investigations in aquiculture 494 



Pond-fish culture 495 



Trout culture 499 



Fish diseases 503 



California trout investigations 505 



Limnological investigations in the national parks and forests 506 



Oyster investigations 51Q 



Physiology of spawning 510 



South Atlantic oyster studies 511 



Control of starfish 516 



Pacific coast OA'ster studies 519 



Alaska razor-clam investigation 521 



Mussel investigations and pollution studies 521 



Pollution studies 522 



Mussel investigations 524 



Activities of the fisheries biological laboratories 525 



Woods Hole, Mass 525 



Beaufort, N. C 526 



Appropriations 529 



' Appendix III to the Report of the U ^ .Commissioner of Fisheries for 1932i Approved for publication, 

 June 16, 1932 



441 



