RAPPORTS ET PROCÈS-VERBAUX DES RÉUNIONS VOLUM E 184

FISHERIES ACOUSTICS

A Symposium held in Bergen, 21—24 June 1982

E dited by

R. E. CRAIG

CONSEIL INTERNATIONAL POUR L'EXPLORATION DE LA MER PALÆGADE 2-4 DK-1261 COPENHAGUE K DANEMARK

ISSN 0074-4336 Août 1984

RAPPORTS ET PROCÈS-VERBAUX DES RÉUNIONS VOLUME 184

FISHERIES ACOUSTICS

A Symposium held in Bergen, 21—24 June 1982

Edited by

R. E. CRAIG

CONSEIL INTERNATIONAL POUR L’EXPLORATION DE LA MER PALÆGADE 2-4 DK-1261 COPENHAGUE K DANEMARK

ISSN 0074-4336 Août 1984 Printed in Denmark by AiO Print Ltd, Odense Table of contents

Page Fisheries acoustics. Introduction, by R. E. C raig...... 5 Fisheries acoustics: a review of general principles, by D. N. MacLennan and S. T. F orbes 7 Physical calibration, by J. E. B lue...... 19 Fish and other organisms as acoustic targets, by L.Midttun...... 25 Techniques and considerations in the design of acoustic surveys, by R. Shotton and G. P. Bazigos 34 Questions relating to beamshape. Subject group A, by T. J. C arlson...... 58 Other physical principles. Subject group B, by J. E. Ehrenberg...... 60 Calibration of equipment. Subject group C, by B. J. Robinson...... 62 Target-strength experimental studies. Subject group D, by J. D a le n ...... 68 Target-strength measurements in situ. Subject group E, by E. Marchai...... 73 Special aspects of target strength (TS). Subject group F, by K. O lsen...... 81 School and multiple echoes. Subject group G, by K. G. Foote...... 84 Classification, special techniques, and data handling. Subject group H, by B. Morgenstern 96 Survey results and applications. Subject group I, by H. i Jâkupsstovu...... 113 Comparison with other methods. Subject group J, by R. S. B ailey...... 119 Equipment and systems. Subject group K, by R. B. Mitson ...... 123 Statistics and survey design. Subject group L, by J. G. Pope...... 128 Plankton and krill studies. Subject group M, by H. U. Thiel...... 134 List of papers submitted to the Symposium...... 142 List of participants...... 146

The first volume in this series was published in 1903, and most of the volumes are still available. A list of titles with current prices may be obtained from the Secretariat of the International Council for the Exploration of the Sea, Palægade 2 -4 , DK-1261 Copenhagen K, Denmark.

The latest volumes are as follows: Vol. 169: The Biology of the Seal. A Symposium held at the University of Guelph, Ontario, Canada, 14—17 August 1972 (1975) D.Kr. 255.00 Vol. 170: Hydro-acoustics in Fisheries Research. A Symposium held in Bergen, 19-22 June 1973 (1977) D.Kr. 160.00 Vol. 171: Petroleum Hydrocarbons in the Marine Environment. Proceedings from ICES Workshop held in Aberdeen, 9—12 September 1975 (1977) D.Kr. 140.00 Vol. 172: North Sea Fish Stocks - Recent Changes and their Causes. A Symposium held in Aarhus, 9 -1 2 July 1975 (1978) D.Kr. 240.00 Vol. 173: Marine Ecosystems and Fisheries Oceanography. Four Symposia of the Joint Oceanic Assembly held in Edinburgh, 13-24 September 1976 (1978) D.Kr. 125.00 Vol. 174: Eel Research and Management. A Symposium held in Helsinki. 9-11 June 1976 (1979) D.Kr. 100.00 Vol. 175: Population Assessments of Shellfish Stocks. A Special Meeting held in Charlot- tenlund. 29 September—1 October 1976 (1979) D.Kr. 155.00 Vol. 176: ICES/ICNAF Joint Investigation on North Atlantic Salmon (1980) D.Kr. 95.00 Vol. 177: Assessment and Management of Pelagic Fish Stocks. A Symposium held in Aber­ deen, 3 -7 July 1978 (1980) D.Kr. 310.00 Vol. 178: Early Life History of Fish: Recent Studies. A Symposium held in Woods Hole, 2 -5 April 1979 (1981) D.Kr. 370.00 Vol. 179: Biological Effects of Marine Pollution and the Problems of Monitoring. Proceed­ ings from ICES Workshop held in Beaufort, North Carolina, 26 February- 2 March 1979 (1980) D.Kr. 220.00 Vol. 180: The Canary Current: Studies of an Upwelling System. A Symposium held in Las Palmas. 11-14 April 1978 (1982) D.Kr. 345.00 Vol. 181: Sediment and Pollution Interchange in Shallow Seas. Proceedings from ICES Workshop held in Texel, 24—26 September 1979 (1981) D.Kr. 105.00 Vol. 182: Diseases of Commercially Important Marine Fish and Shellfish. A Special Meeting held in Copenhagen, 1—3 October 1980 (1983) D.Kr. 140.00 Vol. 183: The Biological Productivity of North Atlantic Shelf Areas. A Symposium held in Kiel, 2 -5 March 1982 (1984) D.Kr. 220.00 Vol. 184: Fisheries Acoustics. A Symposium held in Bergen, 21—24 June 1982 (1984) D.Kr. 150.00 Vol. 185: Hydrobiological Variability in the North Atlantic and Adjacent Seas. In press.

Subscriptions or standing orders should be placed with C. A. Reitzel A/S, Forlag og Boghandel, Nørregade 20, DK-1165 Copenhagen K, Denmark.

Single volumes or back-number sets may be ordered from C. A. Reitzel A/S or from the ICES Secretariat, Palægade 2 -4 , DK-1261 Copenhagen K, Denmark. Prices do not include mailing costs.

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