See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/264276296 Scoping study of the potential spread and impact of the exotic fish Oriental weatherloach in the Murray-Darling Basin, Australia: A resource document. Report to Agriculture, Fisher... Technical Report · August 2002 CITATIONS READS 4 50 3 authors, including: Wayne M. Koster Tarmo Raadik Department of Environment, Land, Water a… Arthur Rylah Institute for Environmental Re… 17 PUBLICATIONS 196 CITATIONS 76 PUBLICATIONS 363 CITATIONS SEE PROFILE SEE PROFILE All in-text references underlined in blue are linked to publications on ResearchGate, Available from: Wayne M. Koster letting you access and read them immediately. Retrieved on: 28 July 2016 SSCOPING SSTUDY OF THE PPOTENTIAL SSPREAD AND IIMPACT OF THE EEXOTIC FFISH OORIENTAL WWEATHERLOACH IN THE MMURRAY--DDARLING BBASIN,, AAUSTRALIA:: AA RReessoouurrccee DDooccuummeenntt Funded under the Murray-Darling 2001 FishRehab Program (A program of the Natural Heritage Trust) Produced by Freshwater Ecology Arthur Rylah Institute for Environmental Research 2002 © Commonwealth of Australia. Represented by Agriculture, Fisheries and Forestry - Australia. Title Scoping study of the potential spread and impact of the exotic fish Oriental weatherloach in the Murray-Darling Basin, Australia: A resource document. Produced by Wayne M. Koster, Tarmo A. Raadik and Pam Clunie Freshwater Ecology, Arthur Rylah Institute for Environmental Research PO Box 137 Heidelberg Victoria 3084 Telephone: (03) 9450 8600 Facsimile: (03) 9450 8730 Produced for Agriculture, Fisheries and Forestry – Australia. Contact Sue Grant Murray-Darling Basin Policy and Programs Telephone: (02) 6272 5922 Facsimile: (02) 6271 6448 Date August 2002 Photographs © Neil Armstrong. Murray-Darling 2001 FishRehab Program Potential spread and impact of the Oriental weatherloach – RESOURCE DOCUMENT SUMMARY As part of the Murray-Darling 2001 FishRehab Program, the Freshwater Ecology Section of the Victorian Department of Natural Resources and Environment (DNRE) was commissioned by Agriculture, Fisheries and Forestry Australia (AFFA), to undertake a scoping study aimed at collating and investigating aspects of the biology, ecology and distribution of the exotic fish Oriental weatherloach (Misgurnus anguillicaudatus), to determine its potential spread and impacts within the Murray-Darling Basin (MDB). This report represents a resource document to define the biology and ecology of Oriental weatherloach, factors responsible for the continued spread of the species, the distribution and potential range of the species, and the potential risks and impacts of the species. Information was sourced from within and outside of the MDB, including overseas, to provide a comprehensive understanding of current knowledge and identify knowledge gaps, particularly in relation to management of the species. A community awareness campaign was conducted as a component of this project to inform the community and responsible agencies of the project. A draft strategy (Koster et al. 2002) was also developed to provide a framework to guide future management of Oriental weatherloach in the MDB by the community and resource managers. The draft strategy includes a regime to monitor the future spread of the species that involves resource managers and the local community. The draft strategy has been prepared as a separate document to this resource document. The specific tasks of this project were to: 1. Define the potential risk and impacts of Oriental weatherloach to aquatic ecosystems in the MDB; 2. Define factors or conditions influencing the spread of Oriental weatherloach within the MDB; 3. Document the rate and pattern of spread of Oriental weatherloach; 4. Form the basis for a management strategy for the species within the MDB; 5. Scope potential pest species management strategies for containment, reduction or eradication programs; 6. Identify knowledge gaps and priorities for research and management; 7. Increase awareness of the species in the MDB with community groups, government agencies such as fisheries and water managers, other MDB users, and the aquarium industry; and Freshwater Ecology, Arthur Rylah Institute for Environmental Research -- i -- Murray-Darling 2001 FishRehab Program Potential spread and impact of the Oriental weatherloach – RESOURCE DOCUMENT 8. Develop a program to allow for community input in monitoring the future spread of Oriental weatherloach in the MDB. Oriental weatherloach have been introduced accidentally, or intentionally for faunal supplementation, into at least six countries (Allen 1984, Welcomme 1988, Lever 1996), and have established self-sustaining populations in four: Australia, Palau, the Philippines, and continental and oceanic United States of America. Oriental weatherloach (Misgurnus spp.) were imported into Australia, as an ornamental, cold-water fish for the aquarium trade. Weatherloach were banned from importation into Australia in 1986 (Burchmore et al. 1990), though by this stage they had established a number of self-sustaining populations in the wild, and were freely available in the Australian aquarium trade. Oriental weatherloach have been reported from five mainland states and one territory in Australia and have established self- sustaining populations in New South Wales (NSW), Victoria and the Australian Capital Territory (ACT). In Victoria, Oriental weatherloach are established on both sides of the Great Dividing Range. Fish survey data and unconfirmed reports indicate they may occur in seven river basins in the Murray-Darling drainage division, and five river basins in the South-east Coast drainage division. Oriental weatherloach have been recorded from at least seven streams in the south- east of inland NSW (Murrumbidgee River and Murray River basins), and from the Hawkesbury River system and Snowy River systems in coastal NSW. Oriental weatherloach have established self-sustaining populations in at least four river systems in the Murrumbidgee River basin in the ACT. Oriental weatherloach are considered to have a range of biological characteristics that make it a successful invader including broad physiological tolerances, flexible diet, low vulnerability to predation, high reproductive potential and long life-span. Oriental weatherloach have established feral populations in several countries, although evidence for the adverse impact of the species is largely speculative. The spread of Oriental weatherloach in Australia has probably been facilitated by several factors. These include the dumping of unwanted aquarium fish, water diversion schemes for irrigation supply and the associated creation of modified habitats such as ricefields, illegal use as baitfish by anglers, and natural dispersal. However, the significance of possible factors in the species' spread is not well understood. Established populations of Oriental weatherloach are not actively managed in any state or territory in Australia, nor is the species managed at a national level. Management within states appears to be ad hoc and reactionary. Whilst we know little about the potential impact of Oriental weatherloach, experience in pest management in Australia suggests a precautionary approach should be applied. Precautionary principles to minimise the risk of future introductions, and pest management principles to address existing introductions (MDBC 2002), should be applied within and outside of the MDB. Freshwater Ecology, Arthur Rylah Institute for Environmental Research -- ii -- Murray-Darling 2001 FishRehab Program Potential spread and impact of the Oriental weatherloach – RESOURCE DOCUMENT Very few methods of control of Oriental weatherloach have been trialed in any depth in Australia, or overseas. Given the key features of this species which include its small size, cryptic nature, and potential for large population sizes, the ability to destroy entire populations is extremely unlikely. At present control options appear limited, with the greatest potential for success being directed at small sized standing waterbodies such as dams and ponds. The environmental adaptability, high competitive ability, high reproductive output, high survivorship and high dispersal ability of Oriental weatherloach indicate that this species could potentially expand its range over a large portion of the MDB, as well as the southeastern coast region of Australia. The ecological impacts of Oriental weatherloach are poorly understood, as are the methods of containment and eradication. More research is required on key areas to better understand its impacts on the aquatic environment, rate and method of spread, as well as the possible methods for containment and control. Freshwater Ecology, Arthur Rylah Institute for Environmental Research -- iii -- Murray-Darling 2001 FishRehab Program Potential spread and impact of the Oriental weatherloach – RESOURCE DOCUMENT ACKNOWLEDGMENTS We wish to thank the following people who contributed during the collation of this document: First and foremost, the steering committee which comprised: • Peter Gillard and Sue Grant, AFFA, Canberra • Mark Lintermans, Environment ACT, Canberra • Rachel Mackenzie, Queensland DPI, Brisbane • Bob Faragher, NSW Fisheries, Cronulla, Sydney. Mark Lintermans is especially acknowledged for providing access to unpublished data. The following people were contacted during the course of this project, and earlier, and provided additional information (listed as `personal communications’ in