Fisheries Research Report No. 294 Resource Assessment Report Temperate Demersal Elasmobranch Resource of Western Australia Matias Braccini, Nick Blay, Alex Hesp & Brett Molony November 2018 Correct citation: Braccini, M., Blay, N., Hesp, A. & Molony, B. 2018. Resource Assessment Report Temperate Demersal Elasmobranch Resource of Western Australia. Fisheries Research Report No. 294 Department of Primary Industries and Regional Development, Western Australia. 149 pp. Enquiries: WA Fisheries and Marine Research Laboratories, PO Box 20, North Beach, WA 6920 Tel: +61 8 9203 0111 Email: [email protected] Website: www.fish.wa.gov.au A complete list of Fisheries Research Reports is available online at www.fish.wa.gov.au Important disclaimer The Chief Executive Officer of the Department of Primary Industries and Regional Development and the State of Western Australia accept no liability whatsoever by reason of negligence or otherwise arising from the use or release of this information or any part of it. Department of Primary Industries and Regional Development Gordon Stephenson House 140 William Street PERTH WA 6000 Telephone: (08) 6551 4444 Website: dpird.wa.gov.au ABN: 18 951 343 745 ISSN: 1035-4549 (Print) ISBN: 978-1-921258-18-3 (Print) ISSN: 2202-5758 (Online) ISBN: 978-1-921258-19-0 (Online) Copyright © State of Western Australia (Department of Primary Industries and Regional Development) 2018 Fisheries Research Report [Western Australia] No. 294 ii Table of Contents Executive Summary ................................................................................................................. 1 2. Scope.................................................................................................................................. 3 3. How the Department Operates ....................................................................................... 3 4. Aquatic Environment ...................................................................................................... 4 4.1 West Coast Bioregion ................................................................................................. 5 4.2 South Coast Bioregion ................................................................................................ 6 5. Resource Description ....................................................................................................... 7 5.1 Resource ...................................................................................................................... 7 5.2 Selection of Indicator Species for Resource ............................................................. 7 6. Species Descriptions ......................................................................................................... 8 6.1 Whiskery shark ........................................................................................................... 8 6.1.1 Taxonomy and Distribution ................................................................................ 8 6.1.2 Stock Structure .................................................................................................... 9 6.1.3 Life History ......................................................................................................... 9 6.2 Gummy shark ........................................................................................................... 11 6.2.1 Taxonomy and Distribution .............................................................................. 11 6.2.2 Stock Structure .................................................................................................. 11 6.2.3 Life History ....................................................................................................... 12 6.3 Dusky shark .............................................................................................................. 14 6.3.1 Taxonomy and Distribution .............................................................................. 14 6.3.2 Stock Structure .................................................................................................. 14 6.3.3 Life History ....................................................................................................... 15 6.4 Sandbar shark ........................................................................................................... 16 6.4.1 Taxonomy and Distribution .............................................................................. 17 6.4.2 Stock Structure .................................................................................................. 17 6.4.3 Life History ....................................................................................................... 17 7. Fishery Information ....................................................................................................... 19 7.1 Temperate Demersal Gillnet and Demersal Longline Fisheries ........................... 19 7.1.1 History of Development ................................................................................... 20 7.1.2 Current Fishing Activities ................................................................................. 22 7.2 Northern Shark Fisheries ........................................................................................ 23 7.2.1 History of Development ................................................................................... 24 7.2.2 Current Fishing Activities ................................................................................. 25 Fisheries Research Report [Western Australia] No. 294 iii 7.3 Fishing Methods ....................................................................................................... 25 7.3.1 Commercial Fishery .......................................................................................... 25 7.3.2 Recreational Fishery ......................................................................................... 28 7.3.3 Customary Fishing ............................................................................................ 30 7.4 Susceptibility ............................................................................................................. 30 8. Fishery Management ..................................................................................................... 30 8.1 Management System ................................................................................................ 30 8.2 Harvest Strategy ....................................................................................................... 33 8.2.1 Current framework ............................................................................................ 33 8.2.2 Proposed framework ......................................................................................... 35 8.2.3 Design ............................................................................................................... 37 8.2.4 Evaluation ......................................................................................................... 38 8.2.5 Monitoring ........................................................................................................ 38 8.2.6 Review .............................................................................................................. 38 8.2.7 Shark Finning.................................................................................................... 38 8.2.8 Reference Points ............................................................................................... 39 8.2.9 Control Rules and Tools ................................................................................... 41 8.3 External Influences................................................................................................... 42 9. Information and Monitoring ......................................................................................... 42 9.1 Range of Information ............................................................................................... 42 9.2 Monitoring ................................................................................................................ 45 9.2.1 Commercial Catch and Effort ........................................................................... 45 9.2.2 Recreational Fishing ......................................................................................... 46 9.2.3 Fishery-Independent Monitoring ...................................................................... 47 9.3 Data Governance ...................................................................................................... 47 9.3.1 Data Storage (non-public) ................................................................................. 47 9.3.2 Data Treatment (non-public)............................................................................. 47 10. Stock Assessment ............................................................................................................ 48 10.1 Principles ................................................................................................................. 48 10.2 Assessment Overview ............................................................................................. 49 10.2.1 Peer Review of Assessment ............................................................................ 49 10.3 Analyses and Assessments ...................................................................................... 49 10.3.1 Data Used in Assessment ...............................................................................