Development and evaluation of egg-based stock assessment methods for blue mackerel Scomber australasicus in southern Australia Editors: T. M. Ward and P. J. Rogers Contributing authors: J.P. Keane, M. Lowry, L.J. McLeay, F.J. Neira, J.R. Ovenden, P.J. Rogers, R.J. Saunders, D. Schmarr, T.M. Ward, I.D. Whittington and D. Williams Report to the Fisheries Research and Development Corporation Project No. 2002/061 Development and evaluation of egg-based stock assessment methods for blue mackerel Scomber australasicus in southern Australia Editors: T. M. Ward and P. J. Rogers Contributing authors: 2J.P. Keane, 3M. Lowry, 1L.J. McLeay, 2F.J. Neira, 6J.R. Ovenden, 1P.J. Rogers, R.J. 1Saunders, 1,4D. Schmarr, 1T.M. Ward, 4,5I.D. Whittington and 3D. Williams Addresses: 1. South Australian Research and Development Institute PO Box 120 Henley Beach, Adelaide, SA, 5024 2. Tasmanian Aquaculture and Fisheries Institute Private Bag 49, Marine Research Laboratories, University of Tasmania, Hobart, Tas, 7001 3. NSW Department of Primary Industries, PO Box 21, Cronulla, NSW, 2230 4. Marine Parasitology Laboratory, School of Earth and Environmental Sciences, The University of Adelaide, Adelaide 5005, SA. 5. Monogenean Research Laboratory, Parasitology Section, The South Australian Museum, Adelaide 5000, SA. 6. Molecular Fisheries Laboratory, Queensland Department of Primary Industries and Fisheries, Floor 6, North Tower, Queensland Biosciences Precinct, University of Queensland 4072, Qld. DISCLAIMER The authors do not warrant that the information in this report is free from errors or omissions. The authors do not accept any form of liability, be it contractual, tortious or otherwise, for the contents of this report or for any other consequences arising from its use or any reliance placed upon it. The information, opinions and advice contained in this report may not relate to, or be relevant to, a reader’s particular circumstances. Opinions expressed by the authors are the individual opinions of those persons and are not necessarly those of the publisher or research provider. ©2007 SARDI Aquatic Sciences This publication is protected by copyright. Apart from any use as permitted under the Copyright Act 1968. No part may be reproduced by any process without prior written permission from the authors. Printed on Reviewers: Dr Qifeng Ye, Dr A Linnane and Dr Stephen Mayfield Approved by: Dr Qifeng Ye Signed: Date: 29/06/2007 Distribution: Fisheries Research and Development Corporation and SARDI Aquatic Sciences Library Circulation Public Domain ISBN 0 7308 5367 5 Small pelagic fish species described in this report. (Drawings courtesy of Fishbase www.fishbase.org, 30th June 2007) Blue mackerel Scomber australasicus Jack mackerel/yellowtail scad Trachurus spp. Sardine Sardinops sagax Maray/Round herring Etrumeus teres Australian anchovy Engraulis australis Table of Contents Non-technical Summary………………………………………………………17 1. General Introduction ................................................................................. 23 1.1 Background ...................................................................................................................23 1.2 Need ..............................................................................................................................27 1.3 Original Objectives .......................................................................................................29 1.4 Revised Objectives ........................................................................................................29 1.5 References ..................................................................................................................... 31 2. Fisheries, surveys and stock assessment options for blue mackerel Scomber australasicus in southern Australia. ............................................... 33 2.1 Introduction...................................................................................................................34 2.2 Taxonomy and Distribution .........................................................................................34 2.3 Fisheries ........................................................................................................................34 2.3.1 International Fisheries...................................................................................................................34 2.3.2 Australian Fisheries .......................................................................................................................35 2.3.2.1 Small Pelagic Fishery....................................................................................................................35 2.3.2.2 Other Commonwealth Fisheries.....................................................................................................36 2.3.2.3 South Australia ...........................................................................................................................36 2.3.2.4 New South Wales ........................................................................................................................37 2.3.2.5 Queensland...................................................................................................................................39 2.3.2.6 Tasmania.....................................................................................................................................39 2.3.2.7 Victoria .......................................................................................................................................41 2.3.2.8 Western Australia........................................................................................................................41 2.3.2.9 Australian Recreational Fishery ...................................................................................................42 2.4 Surveys in southern Australia........................................................................................43 2.4.1 Southern Australia .........................................................................................................................43 2.4.1.1 Russian Surveys (1965–1968).....................................................................................................43 2.4.1.2 British United Trawlers (1977–1979).........................................................................................44 2.4.1.3 Denebola (1979–1980)...............................................................................................................44 2.4.1.4 FRV Warreen.............................................................................................................................44 2.4.2 Eastern Australia............................................................................................................................44 2.4.2.1 FRV Kapala...............................................................................................................................44 2.5 Stock assessment methods ...........................................................................................45 2.6 Discussion.....................................................................................................................47 2.7 Acknowledgements.......................................................................................................48 2.8 References.....................................................................................................................49 3. Techniques for discriminating stocks of blue mackerel Scomber australasicus.................................................................................................. 53 3.1 Introduction...................................................................................................................54 3.2 Materials and Methods .................................................................................................57 3.2.1 Genetic analysis..............................................................................................................................58 3.2.2 Parasite analysis..............................................................................................................................58 3.2.3 Otolith microchemistry.................................................................................................................59 3.3 Results........................................................................................................................... 61 3.3.1 Genetic analysis..............................................................................................................................61 3.3.2 Parasite analysis..............................................................................................................................61 4 3.3.3 Otolith Microchemistry ................................................................................................................66 3.4 Discussion..................................................................................................................... 71 3.4.1 Genetic analysis..............................................................................................................................71 3.4.2 Parasite analysis..............................................................................................................................72 3.4.3 Otolith microchemistry.................................................................................................................74