A Risk Assessment of the Impacts of Pest Species in the Riverine Environment in the Murray-Darling Basin Report to the Murray- Darling Basin Commission Funded by the Strategic Investigations and Education Riverine Program - Project R2006 Freshwater Ecology, Arthur Rylah Institute for Environmental Research, Keith Turnbull Research Institute & Dr Jane Roberts February 2002 A Risk Assessment of the Impacts of Pest Species in the Riverine Environment in the Murray-Darling Basin. Report produced for Murray-Darling Basin Commission, Strategic Investigations and Riverine Program – Project R2006. Prepared by Pam Clunie1, Ivor Stuart1, Matthew Jones1, Di Crowther1, Sabine Schreiber1, Shanaugh McKay1, Justin O'Connor1, & David McLaren2, John Weiss2, Lalith Gunasekera2 & Dr. Jane Roberts3 1 Arthur Rylah Institute for Environmental Research, DNRE 2 Keith Turnbull Research Institute, DNRE 3 Consultant Published by: Department of Natural Resources and Environment Arthur Rylah Institute 123 Brown Street Heidelberg, Victoria, 3084 February 2002 Copyright State Government of Victoria, Department of Natural Resources and Environment 2002. ISBN http://resourceweb/corpmgt/webservices/online.htm Cover Photos: Potamopyrgus antipodarum Steve Morton Salvinia molesta John Weiss Cyprinus carpio Matthew Jones Salix sp. Phil Papas This publication may be of assistance to you but the State of Victoria and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication. Table of Contents TABLE OF CONTENTS.................................................................................................................................I LIST OF FIGURES ........................................................................................................................................... III LIST OF TABLES............................................................................................................................................. III EXECUTIVE SUMMARY .............................................................................................................................V CONTEXT........................................................................................................................................................ V OBJECTIVES, TASKS AND OUTPUTS ............................................................................................................... V RISK ASSESSMENT ........................................................................................................................................ VI EDUCATION ................................................................................................................................................... VI CANVASSING EXPERT OPINION....................................................................................................................VII RESEARCH PORTFOLIO................................................................................................................................VIII 1 INTRODUCTION ......................................................................................................................... 1 1.1 BACKGROUND.................................................................................................................................. 1 1.2 OBJECTIVES ..................................................................................................................................... 1 1.3 DEFINITIONS - WHAT IS A PEST ? .................................................................................................... 1 2 RISK ASSESSMENTS.................................................................................................................. 7 2.1 AQUATIC AND RIPARIAN WEED RISK ASSESSMENT ....................................................................... 7 2.2 RISK ASSESSMENT FOR PEST FAUNA............................................................................................. 24 3 REVIEW OF EDUCATIONAL MATERIAL.......................................................................... 28 3.1 METHODS....................................................................................................................................... 28 3.2 RESULTS/OUTPUTS ........................................................................................................................ 28 3.3 CONCLUSIONS AND RECOMMENDATIONS ..................................................................................... 36 3.4 MURRAY-DARLING BASIN INVASIVE SPECIES EDUCATION PROGRAM ........................................ 37 4 IDENTIFICATION OF CURRENT AND POTENTIAL PEST SPECIES - FAUNA.......... 40 4.1. METHODS....................................................................................................................................... 40 4.2 QUESTIONS AND ANSWERS............................................................................................................ 42 5 IDENTIFYING CURRENT AND POTENTIAL PEST PLANT SPECIES .......................... 56 5.1 IDENTIFICATION............................................................................................................................. 56 5.2 MANAGEMENT ISSUES................................................................................................................... 57 5.3 RESEARCH; INFORMATION & EDUCATION .................................................................................... 57 5.4 BUILDING ON THE QUESTIONNAIRE............................................................................................... 60 6 SPECIES’ PROFILES ................................................................................................................ 63 6.1 FISH........................................................................................................................................................ 64 6.1.1: Cyprinus carpio (Carp) ...............................................................................................................64 6.1.2: Gambusia holbrooki (Eastern Gambusia) ..................................................................................67 6.1.3: Carassius auratus (Goldfish).......................................................................................................71 6.1.4: Perca fluviatilis (Redfin)..............................................................................................................74 i 6.1.5: Misgurnus anguillicaudatus (Oriental Weatherloach) ..............................................................77 6.1.6: Salmo trutta (Brown Trout).........................................................................................................80 6.1.7: Oreochromis mossambicus (Mozambique Tilapia) ....................................................................83 6.1.8: Oncorhynchus mykiss (Rainbow Trout) ....................................................................................85 6.1.9: Tinca tinca (Tench).....................................................................................................................88 6.1.10: Rutilius rutilius (Roach) ...........................................................................................................90 6.1.11: Poecilia reticultata (Guppy)......................................................................................................92 6.1.12: Salmo salar (Atlantic Salmon) ..................................................................................................94 6.1.13: Salvelinus fontinalis (Brook Trout)..........................................................................................96 6.2 INVERTEBRATES............................................................................................................................... 98 6.2.1 Cherax tenuimanus (Marron).......................................................................................................98 6.2.2 Pseudosuccinea columella (American ribbed fluke snail).........................................................100 6.2.3 Potamopyrgus antipodarum (New Zealand mudsnail) ..............................................................102 6.2.4 Dreissena polymorpha (Zebra mussel).......................................................................................104 6.3 PLANTS .............................................................................................................................................. 106 6.3.1 Lippia Phyla canescens (Kunth) E.Greene .................................................................................106 6.3.2 Willows (Salix spp.) .....................................................................................................................109 7 RESEARCH PROJECTS: BRIEFS ...................................................................................... 113 7.1 METHODS..................................................................................................................................... 113 7.2 DEVELOPMENT AND SCOPE OF PROJECTS .................................................................................... 113 7.3 OUTLINE AND SUMMARY OF PROJECTS ....................................................................................... 114 7.4 RESEARCH PROJECT BRIEFS .......................................................................................................