Final Report Evaluating wetland restoration success: feral pig fencing for conservation of Round Hill Reserve Nathan Waltham, Christina Buelow and Jordan Iles Evaluating wetland restoration success: feral pig fencing for conservation of Round Hill Reserve Nathan J. Waltham, Christina A. Buelow and Jordan A. Iles TropWATER, Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University Supported by the Australian Government’s National Environmental Science Program Project 3.3.2 Evaluating wetland system repair projects in GBR catchments © James Cook University, 2020 Creative Commons Attribution Evaluating wetland restoration success: feral pig fencing for conservation of Round Hill Reserve is licensed by James Cook University for use under a Creative Commons Attribution 4.0 Australia licence. For licence conditions see: https://creativecommons.org/licenses/by/4.0/ National Library of Australia Cataloguing-in-Publication entry: 978-1-925514-70-4 This report should be cited as: Waltham, N.J., Buelow, C.A., and Iles, J.A. (2020) Evaluating wetland restoration success: feral pig exclusion fencing in the Round Hill Reserve. Report to the National Environmental Science Program. Reef and Rainforest Research Centre Limited, Cairns (96pp.). Published by the Reef and Rainforest Research Centre on behalf of the Australian Government’s National Environmental Science Program (NESP) Tropical Water Quality (TWQ) Hub. The Tropical Water Quality Hub is part of the Australian Government’s National Environmental Science Program and is administered by the Reef and Rainforest Research Centre Limited (RRRC). The NESP TWQ Hub addresses water quality and coastal management in the World Heritage listed Great Barrier Reef, its catchments and other tropical waters, through the generation and transfer of world-class research and shared knowledge. This publication is copyright. The Copyright Act 1968 permits fair dealing for study, research, information or educational purposes subject to inclusion of a sufficient acknowledgement of the source. The views and opinions expressed in this publication are those of the authors and do not necessarily reflect those of the Australian Government. While reasonable effort has been made to ensure that the contents of this publication are factually correct, the Commonwealth does not accept responsibility for the accuracy or completeness of the contents, and shall not be liable for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the contents of this publication. Cover photograph: (front and back) Roundhill Reserve feral pig fence. Images: S. Jackson.. This report is available for download from the NESP Tropical Water Quality Hub website: http://www.nesptropical.edu.au Restoring coastal wetlands: feral pig exclusion fence case study CONTENTS Contents .................................................................................................................................. i List of Tables ......................................................................................................................... iii List of Figures ......................................................................................................................... v Acronyms ............................................................................................................................... x Abbreviations ........................................................................................................................ xi Acknowledgements .............................................................................................................. xii Executive Summary .............................................................................................................. 1 1.0 Introduction ..................................................................................................................... 5 1.1 Coastal wetland values and services ........................................................................... 5 1.2 Conservation fences .................................................................................................... 6 1.3 Feral pig disturbance in GBR catchments .................................................................... 6 1.3 Round Hill Reserve ...................................................................................................... 8 1.4 Project objectives ......................................................................................................... 8 2.0 Study location .................................................................................................................10 2.1 Study location and values evaluation approach ..........................................................10 2.2 Restoration success indicators ....................................................................................11 2.2.1 Water quality ........................................................................................................11 2.2.2 Vegetation ............................................................................................................12 2.2.3 Biodiversity ...........................................................................................................13 3.0 Values and Services .......................................................................................................14 3.1 Carbon dynamics: soil properties and saltmarsh decomposition .................................14 3.1.1 Introduction...........................................................................................................14 3.1.2 Methods ...............................................................................................................14 3.1.3 Results and Discussion ........................................................................................17 3.2 Vegetation extent and composition .............................................................................28 3.2.1 Introduction...........................................................................................................28 3.2.2 Methods ...............................................................................................................29 3.2.3 Results and Discussion ........................................................................................33 3.4 Water Quality and Faunal Biodiversity ........................................................................52 3.4.1 Introduction...........................................................................................................52 3.4.2 Methods ...............................................................................................................53 3.4.3 Results and Discussion ........................................................................................56 4.0 Synthesis ........................................................................................................................72 4.1 Efficacy of feral pig exclusion fencing ..........................................................................72 i Waltham et al. 4.2 Maintenance of fences in coastal areas ......................................................................73 4.3 Conservation fence improvement ................................................................................74 4.3 Limiting cattle stock access to wetlands ......................................................................78 4.4 Invasive fish management ..........................................................................................79 4.5 Values based approach to wetland conservation ........................................................80 4.6 Final remark ................................................................................................................85 5.0 Conclusions ....................................................................................................................86 References ...........................................................................................................................87 ii Restoring coastal wetlands: feral pig exclusion fence case study LIST OF TABLES Table 1. Restored and reference wetland location descriptions. ..................................10 Table 2. Permutational test for analysis of variance (PERMANOVA) of the rate of carbon decomposition in saltmarsh soils. ..................................................................25 Table 3. Classes and associated classification cues used to generate training samples for pixel based image classification in ArcGIS................................................31 Table 4. Summary of when vegetation quadrat surveys and UAV surveys were conducted. .....................................................................................................33 Table 5. Plant species detected at wetland locations during quadrat surveys. .............33 Table 6. Permutation tests for homogeneity of multivariate dispersion (PERMDISP) of vegetation percent cover between Trip (Jul-2018, Jun-2019), Location (RH1, RH2, RH3, RH4, RH5) and Position (Low, High). Permutation: free. Number of permutations: 9999. .......................................................................................37 Table 7. Permutational multivariate analysis of variance (PERMANOVA) of vegetation percent cover between Trip (Jul-2018, Jun-2019), Location (RH1, RH2, RH3, RH4, RH5) and Position (Low, High). Permutation: free. Number of permutations: