U.S. Department 

 of Commerce 



Robert Mosbacher 

 Secretary 



National Oceanic 

 and Atmospheric 

 Administration 



John A. Knauss 

 Under Secretary for 

 Oceans and Atmosphere 



National Marine 

 Fisheries Service 



William W. Fox. Jr. 

 Assistant Administrator 

 for Fisheries 



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Scientific Editor 

 Dr. Linda L. Jones 



National Marine Mammal Laboratory 

 National Marine Fisheries Service, NOAA 

 7600 Sand Point Way NE 

 Seattle. Washington 98 1 1 5-0070 



Editorial Committee 



Dr. Andrew E. Dizon National Marine Fisheries Service 

 Dr. Charles W. Fowler National Marine Fisheries Service 

 Dr. Richard D. Methot National Marine Fisheries Service 

 Dr. Theodore W. Pietsch University of Washington 

 Dr. Joseph E. Powers National Marine Fisheries Service 

 Dr. Tim D. Smith National Marine Fisheries Service 

 Dr. Mia J. Tegner Scripps Institution of Oceanography 



The Fishery Bulletin (ISSN 0090-0656) 

 is published quarterly by the Scientific 

 Publications Office, National Marine 

 Fisheries Service, NOAA, 7600 Sand 

 Point Way NE, BIN C15700, Seattle, WA 

 98115-0070. Second class postage is paid 

 in Seattle, Wash., and additional offices. 

 POSTMASTER send address changes for 

 subscriptions to Fishery Bulletin, Super- 

 intendent of Documents, U.S. Govern- 

 ment Printing Office, Washington, DC 

 20402. 



Although the contents have not been 

 copyrighted and may be reprinted entire- 

 ly, reference to source is appreciated. 



The Secretary of Commerce has deter- 

 mined that the publication of this period- 

 ical is necessary in the transaction of the 

 public business required by law of this 

 Department. Use of funds for printing of 

 this periodical has been approved by the 

 Director of the Office of Management and 

 Budget. 



For sale by the Superintendent of 

 Documents, U.S. Government Printing 

 Office, Washington, DC 20402. Subscrip- 

 tion price per year: $16.00 domestic and 

 $20.00 foreign. Cost per single issue: 

 $9.00 domestic and $11.25 foreign. 



Managing Editor 

 Nancy Peacock 



National Marine Fisheries Service 

 Scientific Publications Office 

 7600 Sand Point Way NE, BIN C 15700 

 Seattle, Washington 981 15-0070 



The Fishery Bulletin carries original research reports and technical notes on investiga- 

 tions in fishery science, engineering, and economics. The Bulletin of the United States 

 Fish Commission was begun in 1881; it became the Bulletin of the Bureau of Fisheries 

 in 1904 and the Fishery Bulletin of the Fish and Wildlife Service in 1941. Separates 

 were issued as documents through volume 46; the last document was No. 1103. Begin- 

 ning with volume 47 in 1931 and continuing through volume 62 in 1963, each separate 

 appeared as a numbered bulletin. A new system began in 1963 with volume 63 in 

 which papers are bound together in a single issue of the bulletin. Beginning with 

 volume 70, number 1, January 1972, the Fishery Bulletin became a periodical, issued 

 quarterly. In this form, it is available by subscription from the Superintendent of 

 Documents, U.S. Government Printing Office, Washington, DC 20402. It is also 

 available free in limited numbers to libraries, research institutions, State and Federal 

 agencies, and in exchange for other scientific publications. 



