Characteristics of the fish fauna of the Mandurah artificial reef Submitted by Lachlan A. W. Ramm This thesis is presented for the degree of Bachelor of Science Honours College of Science, Health, Engineering & Education, of Murdoch University, 2020 Declaration I declare that this thesis is my own account of my research and contains as its main content work which has not previously been submitted for a degree at any tertiary education institution Lachlan Ramm i Acknowledgements I would like to thank a number of people who have helped made the submission of this thesis possible. Firstly, a massive thanks to my primary supervisor, Dr James Tweedley, for his endless support and advice. Advances in my knowledge throughout this thesis is a huge credit to yourself and for that I am very grateful. Thank you to my secondary supervisor James Florisson and Steph Watts from Recfishwest for their advice, particularly in Chapter two, as well as Alistair Becker for his contribution to that chapter also. A big thank you to my parents, Julie and Ash, who have supported me financially and emotionally throughout this journey, this one’s for you. Many thanks to my partner Nicola who has been very patient and helpful throughout the stressful milestones of this thesis and for providing transport, food and emotional support when I needed it most. Credit is due for the Reef Vision volunteers that made BRUV deployments on the Mandurah artificial reef at the start of the study, thank you for your efforts. I would also like to thank the many volunteers who assisted my own deployments of BRUV units throughout the 17 months of the study period, specifically Ash, Nathan, Will, Jethro, Luke and Emilie for their efforts on multiple occasions. Thank you Tackle World Miami for donating the bait used in the BRUV units throughout the duration of this study. Finally, it should be acknowledged that funding was provided by Recfishwest and the Department of Primary Industries & Regional Development through the Recreational Fishing Initiatives Fund and by Murdoch University. ii Abstract Artificial reefs have been deployed throughout the world for a range of different purposes and thus differ in their characteristics. To better understand how their designs and implementation differ spatially, temporally and according to their stated purpose, an extensive collation of information on artificial reefs is needed. Furthermore, in Australia and particularly Western Australia, artificial reefs are increasingly being deployed to enhance recreational fishing experiences and catch rates of key species. To address these topics, this thesis aimed to conduct a systematic literature review on existing artificial reefs around the world and describe their characteristics. It also aimed to compare and describe the characteristics of the fish fauna on the recently deployed Mandurah artificial reef (south-western Australia) to those on nearby natural habitat. Finally, a comparison of the fish community of the three ‘Fish Box’ artificial reefs in Mandurah, Bunbury and Dunsborough was conducted. The literature review identified 1,074 unique artificial reefs from 71 countries, with 89% located in the northern hemisphere, but with an equal distribution between east and west. A more in-depth investigation of artificial reefs that were intentionally deployed found that these deployments increased markedly after 1965 and were most commonly sunk between depths of 10 and 30 m. Most reefs were designed to enhance faunal communities and/or fisheries. More affluent countries have monitored artificial reefs using more technologically advanced methods including video systems over recent decades. However, many reef deployments have not had an associated monitoring program and those that do are generally too short to detect long-term temporal changes. Fish and the associated faunal assemblages were monitored on an artificial reef and natural (control) site using Baited Remote Underwater Video (BRUVs) between February 2019 and July 2020. A far greater number of species and individuals were observed on the artificial reef than the control site. Additionally, three key recreational fishing species, i.e. Chrysophrys auratus, Seriola hippos and Pseudocaranx dentex, were also found in far greater abundances on the artificial reef. Pelagic fish were also more iii common on the artificial habitat, likely due to the upward flow diversion produced by the modules and the subsequent increased availability of plankton. While community composition was mainly driven by differences between the artificial reef and control site, the faunas of both sites did change temporally, albeit to a lesser extent. There was a general decrease in the number of species of fish in winter and increase in summer. An aim of this study was to develop a standardized protocol for describing artificial reefs, which is hoped to be adopted globally. If successful, this will allow comparisons between artificial reefs and their outcomes to be made thus increasing our understanding of these reefs and improving their designs. The study also demonstrates that the Mandurah artificial reef supports a distinct faunal community compared with an adjacent natural habitat with no reef, including species that are of recreational importance. A comparison of three ‘Fish Box’ artificial reefs demonstrated that the fauna on the Mandurah reef was the most speciose and harboured the greater number of fish, indicating that site selection has a major influence on the resultant fish community composition and thus should be considered in future reef deployments. iv Table of contents Acknowledgements .................................................................................................... ii Abstract ..................................................................................................................... iii Publication list ........................................................................................................... vi Chapter 1: General introduction ................................................................................. 1 1.1. Artificial reefs ..................................................................................................................... 1 1.2. Artificial reefs in Western Australia ................................................................................... 4 1.3. Recreational fishing ............................................................................................................ 8 1.4. Aims .................................................................................................................................... 9 Chapter 2: Artificial reefs in the Anthropocene: A review of geographical and historical trends in their design, purpose and monitoring ......................................... 10 2.0. Abstract ............................................................................................................................ 10 2.1. Introduction ..................................................................................................................... 11 2.2. Materials and methods .................................................................................................... 14 2.2.1. Collation and analysis of publication data for fisheries enhancement terms .......... 14 2.2.2. Literature search ....................................................................................................... 15 2.2.3. Data extraction and classification ............................................................................. 16 2.3. Results and discussion ..................................................................................................... 19 2.3.1. Number of publications ............................................................................................ 19 2.3.2. Overview ................................................................................................................... 20 2.3.3. Geographical distribution and abundance ............................................................... 23 2.3.4. Trends between the categories of artificial reefs ..................................................... 26 2.3.5. Category C reefs ........................................................................................................ 28 2.4. Conclusions and guidelines for artificial reef description ................................................ 40 Chapter 3: Comparisons between the fish faunas of the Mandurah artificial reef and adjacent unstructured habitat .................................................................................. 43 3.0. Abstract ............................................................................................................................ 43 3.1. Introduction ..................................................................................................................... 44 3.2. Materials and methods .................................................................................................... 46 3.2.1. Study region and artificial reef .................................................................................. 46 3.2.2. Sampling regime ....................................................................................................... 48 3.2.3. Data extraction ......................................................................................................... 50 3.2.4. Statistical analysis ....................................................................................................