Performance Assessment of the Benthic Protection Zone of the Great Australian Bight Marine Park: Epifauna Final report to the South Australian Department for Environment and Heritage and the Commonwealth Department of the Environment, Water, Heritage and the Arts David R. Currie, Shirley J. Sorokin and Timothy M. Ward August 2008 SARDI Aquatic Sciences Publication No. F2008/000647-1 SARDI Research Report Series No. 299 Performance assessment of the BPZ This publication may be cited as: Currie, D.R. Sorokin, S.J. and Ward, T.M. (2008). Performance Assessment of the Benthic Protection Zone of the Great Australian Bight Marine Park: Epifauna. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. South Australian Research and Development Institute SARDI Aquatic Sciences 2 Hamra Avenue West Beach SA 5024 Telephone: (08) 8207 5400 Facsimile: (08) 8207 5406 http://www.sardi.sa.gov.au Disclaimer: The authors warrant that they have taken all reasonable care in producing this report. The report has been through the SARDI Aquatic Sciences internal review process, and has been formally approved for release by the Editorial Board. Although all reasonable efforts have been made to ensure quality, SARDI Aquatic Sciences and Department for Environment and Heritage do not warrant that the information in this report is free from errors or omissions. SARDI Aquatic Sciences and Department for Environment and Heritage do not accept any liability for the contents of this report or for any consequences arising from its use or any reliance placed upon it. © State of South Australia through the Department for Environment and Heritage You may copy, distribute, display, download and otherwise freely deal with this publication for any purpose subject to the conditions that you (1) attribute the Department as the copyright owner of this publication and that (2) you obtain the prior written consent of the Department for Environment and Heritage if you wish to modify the work or offer the publication for sale or otherwise use it or any part of it for a commercial purpose. Written requests for permission should be addressed to: GABMP Manager, PO BOX 22, Port Lincoln SA 5606. Printed in Adelaide: August 2008 SARDI Aquatic Sciences Publication No. F2008/000647-1 SARDI Research Report Series No. 299 ISBN 978-0-7308-5394-7 Author(s): Dr. David R. Currie, Ms. Shirley J. Sorokin, and Dr. Timothy M. Ward Reviewers: Dr. Jason Tanner and Dr. Stephen Mayfield Approved by: Dr. Qifeng Ye Signed: Date: 28 August 2008 Distribution: South Australian Department for Environment and Heritage; Commonwealth Department of the Environment, Water, Heritage and the Arts; Consultative Committee of the Great Australian Bight Marine Park; SARDI Aquatic Sciences Library Circulation: Public Domain SARDI Aquatic Sciences Report - Page i Performance assessment of the BPZ TABLE OF CONTENTS LIST OF FIGURES .............................................................................................................................III LIST OF TABLES ...............................................................................................................................IV LIST OF APPENDICES......................................................................................................................IV EXECUTIVE SUMMARY................................................................................................................... V 1 INTRODUCTION ........................................................................................................................ 1 1.1 OVERVIEW ............................................................................................................................. 1 1.2 REGIONAL GEOMORPHOLOGY ............................................................................................... 1 1.3 REGIONAL BIODIVERSITY ...................................................................................................... 2 1.4 THE GREAT AUSTRALIAN BIGHT MARINE PARK ................................................................... 4 1.5 PERFORMANCE ASSESSMENT OF THE BPZ.............................................................................. 4 1.6 RATIONALE AND OBJECTIVES ................................................................................................ 5 2 METHODS.................................................................................................................................... 5 2.1 EPIFAUNA .............................................................................................................................. 5 2.2 UNDERWATER VIDEO ............................................................................................................. 7 3 RESULTS...................................................................................................................................... 8 3.1 EPIFAUNA .............................................................................................................................. 8 3.1.1 Faunal composition.......................................................................................................... 8 3.1.2 Spatial and temporal variations in species richness and biomass ................................... 9 3.1.3 Spatial and temporal variations in community structure ............................................... 11 3.1.4 Environmental influences............................................................................................... 13 3.1.5 Adequacy of sampling .................................................................................................... 16 3.2 UNDERWATER VIDEO ........................................................................................................... 17 3.2.1 Topography and habitat structure.................................................................................. 17 3.2.2 Epifaunal classification.................................................................................................. 18 3.2.3 Video vs. sled comparison.............................................................................................. 20 4 DISCUSSION.............................................................................................................................. 23 4.1 SPATIAL AND TEMPORAL VARIABILITY IN EPIFAUNA ........................................................... 23 4.2 SLED SAMPLING EFFICIENCY ................................................................................................ 23 4.3 CONSERVATION SIGNIFICANCE ............................................................................................ 23 4.4 BIODIVERSITY AND ENDEMISM ............................................................................................ 24 4.5 EFFICACY OF UNDERWATER VIDEO FOR NON-DESTRUCTIVE SAMPLING ............................... 24 4.6 20-YEAR PERFORMANCE ASSESSMENT PROGRAM................................................................. 26 4.7 FUTURE RESEARCH .............................................................................................................. 27 4.7.1 AUV................................................................................................................................ 27 4.7.2 Swath Bathymetry........................................................................................................... 28 4.7.3 Deep-sea habitats of the BPZ......................................................................................... 29 5 REFERENCES ........................................................................................................................... 29 6 ACKNOWLEDGEMENTS ....................................................................................................... 34 SARDI Aquatic Sciences Report - Page ii Performance assessment of the BPZ LIST OF FIGURES Figure 1. False-colour bathymetric image of the Great Australian Bight showing the wide continental shelf (brown fill; <200 m depth) and continental slope (yellow fill; 200-4500 m depth) surrounding the Benthic Protection Zone. ..............................................................................................................................................1 Figure 2. Location of study area, sedimentary facies (adapted from James et al., 2001) and Benthic Protection Zone of the Great Australian Bight Marine Park. Closed circles indicate locations of sites sampled for epibenthos during the 2002 pilot survey. Numeric codes denoting nine sedimentary facies are as follows: B, Bryozoan; BB, Branching Bryozoan; BI, Bryozoan Intraclast; I, Intraclast; IBE, Intraclast Bryozoan East; IBW, Intraclast Bryozoan West; IM, Intraclast Mollusc; MI, Mollusc Intraclast; Q, Quartzose Skeletal........3 Figure 3. Epibenthic sled used to collect sessile organisms from 40 sampling sites inside and immediately outside the BPZ during October 2006..........................................................................................................................6 Figure 4. Underwater camera system used to quantify epibenthos and seafloor topography at 11 sampling sites inside the BPZ during October 2006. ..............................................................................................................7 Figure 5. Total (a) wet weight and (b) number of species of each major phylum collected during surveys, and (c) the total number of sites (out of 40) at which specimens belonging to each major phylum were collected. Values for each variable