s R KNOWLEDGE Rive EmErging issuEs in AliEn Fish mAnAgEmEnt in thE murrAy-DArling BAsin stAtEmEnt, rECOmmEnDAtiOns AnD suPPOrting PAPErs WOrKshOP hElD in BrisBAnE, 30-31 mAy 2006 EmErging issuEs in AliEn Fish mAnAgEmEnt in thE murrAy-DArling BAsin stAtEmEnt, rECOmmEndatiOns AnD suPPOrting papers WOrKshOP hElD in BrisBAnE, 30-31 mAy 2006 Dean AnsEll AnD PEtEr JacksOn (EDitOrs) Acknowledgements sincere thanks are extended to those who participated in the workshop. A special thanks to Peter Jackson, Peter Kind, natalie Baker, Jim Barrett, mark lintermans and Craig Boys for their efforts in organising and running the event. the workshop was expertly facilitated by Derek Foster. John Koehn and mark lintermans assisted greatly in preparation of the statement and recommendations for the proceedings. JunE 2007 Published by murray-Darling Basin Commission Postal Address GPO Box 409, Canberra ACt 2601 Office location Level 5, 15 moore street, Canberra City, Australian Capital territory telephone (02) 6279 0100 international + 61 2 6279 0100 Facsimile (02) 6248 8053 international + 61 2 6248 8053 E-mail [email protected] internet http://www.mdbc.gov.au For further information contact the murray-Darling Basin Commission office on (02) 6279 0100 this report may be cited as: Ansell, D. and Jackson, P. (Eds). 2007. Emerging Issues in Alien Fish Management in the Murray-Darling Basin: Statement, recommendations and supporting papers. Proceedings of a workshop held in Brisbane QlD, 30-31 may 2006. murray-Darling Basin Commission, Canberra. mDBC Publication no: 16/07 graphic design by Art Direction Creative, manuka ACt isBn: 1 921257 26 1 © Copyright murray-Darling Basin Commission 2007 this work is copyright. graphical and textual information in the work (with the exception of photographs and the mDBC logo) may be stored, retrieved and reproduced in whole or in part, provided the information is not sold or used for commercial benefit and its source Emerging( Issues in Alien Fish Management in the Murray-Darling Basin: Statement, recommendations and supporting papers) is acknowledged. such reproduction includes fair dealing for the purpose of private study, research, criticism or review as permitted under the Copyright Act 1968. reproduction for other purposes is prohibited without prior permission of the murray-Darling Basin Commission or the individual photographers and artists with whom copyright applies. to the extent permitted by law, the copyright holders (including its employees and consultants) exclude all liability to any person for any consequences, including but not limited to all losses, damages, costs, expenses and any other compensation, arising directly or indirectly from using this report (in part or in whole) and any information or material contained in it. the contents of this publication do not purport to represent the position of the murray-Darling Basin Commission. they are presented to inform discussion for improvement of the Basin’s natural resources. 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FEAturEs * ECF – elemental chlorine free * Environmentally sound - produced from managed plantations * Australian made 2 EmErging issuEs in AliEn Fish mAnAgEmEnt in thE murrAy DArling BAsin – WOrKshOP, 30-31 mAy 2006 COntEnts Foreword 5 statement and recommendations 7 Alien species in the context of the native Fish strategy 16 Jim Barrett Overview of the ecology and impact of three alien 22 fish species:r edfin perch,m ozambique mouthbrooder (tilapia) and Oriental weatherloach Mark Lintermans, Tarmo Raadik, David Morgan and Peter Jackson management of pest fish 33 Mike Braysher summary of existing alien fish management 40 mechanisms in murray-Darling Basin jurisdictions Jason Higham managing pest fish in them urray-Darling Basin: 54 lessons learnt from previous invaders John Koehn risk assessment modelling to identify potential fish invaders 60 Mary Bomford Community understanding and attitudes to alien fish 69 Adrian Wells list of participants 73 EmErging issuEs in AliEn Fish mAnAgEmEnt in thE murrAy DArling BAsin – WOrKshOP, 3v0-31 mAy 2006 4 EmErging issuEs in AliEn Fish mAnAgEmEnt in thE murrAy DArling BAsin – WOrKshOP, 30-31 mAy 2006 FOreworD Of the 13 objectives of the native Fish strategy the Workshop examined in detail some of the (nFs), one relates directly to alien species, more pertinent issues relating to alien fish in namely to ‘control and manage alien fish species’. the Basin, including control and management; Another two objectives are relevant in that the prevention and preparedness; policy, reporting improved management of alien fish will assist and decision making; and extension and to protect native fish from threats of disease communication. the need to develop a ‘toolbox’ and parasites, and protect native fish from the of up-to-date management and control adverse effects of translocation and stocking. in techniques was identified by participants.t he addition, ‘controlling alien fish species’ is one of workshop also recommended the development the six driving actions of the nFs. of a Basin-wide alien fish plan and them DBC the nFs aims to ensure that the Basin sustains has consequently provided funding for this viable fish populations and communities initiative, to commence in 2007/08. throughout its rivers. the 50-year goal of the this Workshop is another in a series that nFs is to rehabilitate all native fish species in have been conducted over the last few the Basin back to 60 percent or more of their years to address specific issues under the estimated pre-European settlement levels. banner of the nFs. Previous workshops have importantly, alien fish should not be regarded addressed the need for fishways, thermal as more important than other threatening pollution, translocation and stocking, processes. Without addressing other threats such downstream migration, habitat rehabilitation as habitat degradation, lack of environmental and management, the conservation and flows, barriers to fish passage and various water management of murray cod, and fish in wetlands. quality issues, the goal of the nFs is unlikely to be achieved. this Workshop proceedings is a valuable contribution to the discussion of alien species in the Basin, particularly as it has enunciated an extensive set of recommendations on the way forward, using the objectives of the nFs as a framework. it also progresses discussion on Wendy Craik the management of three particular species. Chief Executive two of these species, redfin perch and Oriental weatherloach, are already present in the Basin but have until now received little attention, whilst the third, tilapia, is dangerously close to the Basin’s northern boundaries. EmErging issuEs in AliEn Fish mAnAgEmEnt in thE murrAy DArling BAsin – WOrKshOP, 3v0-31 mAy 2006 5 6 EmErging issuEs in AliEn Fish mAnAgEmEnt in thE murrAy DArling BAsin – WOrKshOP, 30-31 mAy 2006 EmErging issuEs in AliEn Fish mAnAgEmEnt in thE murrAy-DArling BAsin Workshop 30-31 May 2006 priority action in the development of the Basin- statements and wide alien fish plan. recommendations • it was noted that the wealth of existing international literature on the management of 1. Introduction alien fish species should be acknowledged and We, the participants of the workshop on Emerging utilised in developing management options in Issues in Alien Fish Management the Basin. in the Murray-Darling Basin, held in Brisbane • the workshop participants agreed to a basic on 30 -31 may 2006, and representing a range framework that contains the components of stakeholders, professionals and interests, considered central to the management of alien request that the Commonwealth and state species and is flexible enough to governments and other agencies, community allow interpretation and adoption at a groups and those with an interest in the range of scales. management of alien fish species consider the • Workshop participants agreed that it will following statements and recommendations be critical to invest in a communication and arising from consideration of expert papers education program about the detrimental and discussions. impacts of alien species and the consequences Alien species are here defined as species of moving them to new catchments. Coupled originating overseas and now established in with this should be an increasing investment Australia (harris, 1995). this definition excludes in social research. this should focus on translocated native species and these were not understanding the values, knowledge levels specifically considered at the workshop.h owever and behavioural drivers in communities. workshop participants recognised that many of the recommendations documented here are 3. Reasons for concern equally applicable to these species. 3.1 What is the problem? 2. Summary Conclusions • much emphasis has been placed on the • it was the firm view of the workshop impacts of Carp in the murray-Darling Basin participants that there is an urgent need for with little consideration being given to the alien species management in the Basin to be impact of other species, particularly those that developed and implemented under a Basin- are either not yet widespread (e.g. Oriental wide alien fish plan.t his should be seen as a weatherloach) or are not yet present but have component of, and be driven by the principles the potential to invade the Basin (e.g. tilapia), of the native Fish strategy. it should have or those with economic or social values (e.g. specific objectives, milestones and targets. trout, redfin perch and ornamental fish) in • it was the firm view of the workshop southern states. participants that immediate action to reduce • Whilst definitive data are lacking on the the risk of alien species already in the Basin potential impact of some of these species on spreading further or of new alien species (such the receiving ecosystems, their invasive nature as tilapia) entering the Basin constitutes a suggests that significant impacts are likely. EmErging issuEs in AliEn Fish mAnAgEmEnt in thE murrAy DArling BAsin – WOrKshOP, 3v0-31 mAy 2006 7 • Evidence suggests that there is a limited the Basin and is properly integrated with other capacity to minimise the risk of alien species management actions.