CRC for Australian Weed Management #7 Technical Series Improving the selection, testing and evaluation of weed biological control agents Technical Series #7 • Improving the selection, testing and evaluation of weed biological control agents the selection, testing and evaluation of weed biological control Series #7 • Improving Technical Editors: H. Spafford Jacob and D.T. Briese CRC for Australian Weed Management #7 Technical Series Improving the selection, testing and evaluation of weed biological control agents Proceedings of the CRC for Australian Weed Management Biological Control of Weeds Symposium and Workshop September 13, 2002 University of Western Australia Perth, Western Australia Editors: H. Spafford Jacob and D.T. Briese Improving the selection, testing and evaluation of weed biological control agents the selection, testing and evaluation of weed biological control Improving CRC for Australian Weed Management Technical Series no. 7 April 2003 Copyright © CRC for Australian Weed Management 2003 This book is copyright. Except as permitted under the Australian Copyright Act 1968 (Commonwealth) and subsequent amendments, no part of this publication my be reproduced, stored or transmitted in any form or by any means, electronic or otherwise, without the specific written permission of the copyright owner. Enquiries and additional copies: CRC for Australian Weed Management, Waite Campus, University of Adelaide, PMB 1, Glen Osmond, SA 5064, Australia Telephone: (61) (08) 8303 6590 Fax: (61) (08) 8303 7311 Email: [email protected] www.weeds.crc.org.au ISBN 0-9587010-7-5 Front cover: Larinus latus (Coleoptera: Curculionidae) a biological control agent released against Onopordum thistles in Australia. Photo courtesy of David Briese. ii CRC for Australian Weed Management • Improving the selection, testing and evaluation of weed biological control agents Acknowledgments The Organising Committee would like to thank the CRC for Australian Weed Management and the agents the selection, testing and evaluation of weed biological control Improving University of Western Australia for their contribution to the symposium, workshop and proceedings. Those who attended the symposium and participated in the workshop sessions are acknowledged for their contribution to the improvement of the art and science of weed biological control. We also thank the reviewers who donated their time and expertise to improve the papers included in this proceedings. The Organising Committee Helen Spafford Jacob, School of Animal Biology, University of Western Australia, Perth, W.A. David Briese, CSIRO Entomology, Canberra, A.C.T. Rachel McFadyen, Queensland Department of Natural Resource Management, Alan Fletcher Research Centre, Sherwood, QLD Tim Heard, CSIRO Entomology, Long Pocket Laboratories, Indooroopilly, QLD Andy Sheppard, CSIRO European Laboratory, Montferrier-sur-Lez, France CRC for Australian Weed Management • Improving the selection, testing and evaluation of weed biological control agents iii Symposium and workshop attendees Malcolm Barker Western Australia Shona Lamoureaux New Zealand Kathryn Batchelor Western Australia Corinna Lange Queensland Graham Blacklock Western Australia Deirdre Lemerle New South Wales Graeme Bourdot New Zealand Allan Lord Western Australia David Briese Australian Capital Territory Bert Lukitsch Northern Territory El Bruzzese Victoria Kate McArthur Victoria John Charlton South Australia Rachel McFadyen Queensland Steve Clement United States of America David McLaren Victoria Jamie Cooper Tasmania Louise Morin Australian Capital Territory Jim Cullen Australian Capital Territory Tom Morley Victoria Jamie Davies Tasmania Tom Nordblom New South Wales K. Dhileepan Queensland Janine Paynter Northern Territory Michael Day Queensland Quentin Paynter Northern Territory Graham Donnelly Queensland Karina Potter Tasmania Kylie Evans South Australia Kerry Roberts Victoria Samantha Giles Western Australia Jean-Louis Sagliocco Victoria Hugh Gourlay New Zealand John Scott Western Australia Blair Grace Northern Territory Kirsten Scott Queensland Glenn Graham Queensland Andy Sheppard France Tony Grice Queensland Helen Spafford Jacob Western Australia Richard Groves Australian Capital Territory Peter Stahle Victoria Tim Heard Queensland Geoff Strickland Western Australia Royce Holtkamp New South Wales Anthony Swirepik Australian Capital Territory Ruth Huwer New South Wales Mariano Trevino Queensland John Ireson Tasmania Wayne Vogler Queensland Improving the selection, testing and evaluation of weed biological control agents the selection, testing and evaluation of weed biological control Improving Izquierdo Jordi Spain Trevor Wardill Queensland Mic Julien Queensland Tony Willis Australian Capital Territory Greg Keighery Western Australia Paul Wilson Western Australia Rieks van Klinken Northern Territory Paul Yeoh Western Australia Darren Kriticos Australian Capital Territory Rae Kwong Victoria iv CRC for Australian Weed Management • Improving the selection, testing and evaluation of weed biological control agents Preface Putting more science into the art of biological control agents the selection, testing and evaluation of weed biological control Improving Rick Roush CEO, CRC for Australian Weed Management, Waite Campus, PMB 1, Glen Osmond, SA 5064 For more than 30 years, discussions in learned scientific meetings have often fretted that the practice of classical biological control was more art than science, with heavy reliance on rules-of-thumb based on patterns of practice, but not on experiments. Classical biological control was inspired by the successful control of cottony cushion scale in California in the 1880s, when US government entomologist C. V. Riley recognised that the pest was native to Australia and New Zealand, and sent Walter Koebele to find and bring the scale’s natural enemies back to California. Biological control workers have traditionally been outstanding naturalists and observers, but were often forced for reasons of limited funding to import anything that looked like it would do some good but wouldn’t do any harm (Beirne, 1975). Thus, despite the enormous successes of classical biological control, and the influence of biocontrol and its researchers on the science of animal ecology, many of the key processes and research questions of biological control itself were not often studied until the last decade or so (for examples of such discussions, see Mackauer et al., 1990, Hopper et al., 1993, Hopper & Roush, 1993). As reviewed by David Briese and colleagues in the introductory paper of this collection, there is now a much greater emphasis on trying to improve the efficiency of biological control (eg., through more rational choice of agents likely to be effective) and on reducing the chances of any adverse impacts of natural enemy introductions on native or desirable species. As with biological control more generally, Australia has made major contributions to these questions. Briese et al. note that Australian scientists have been leaders in weed biocontrol since undertaking the near legendary biocontrol of Opuntia cactus in the 1920s. I suggest that this is a tribute not only to the intellectual skills of Australian scientists, but also driven by necessity; Australia must depend on biological control to address many of its weed problems. The vast size of Australia coupled with its low population density (especially outside the 5 major cities and away from the coast lines) means that weed problems of grazing lands and natural ecosystems, in particular, are far too large to be addressed by weed management tactics that require regular human inputs. For much of Australia, biological control is not just an environmentally friendly way to manage weeds and reduce pesticide inputs, it is the only practical way to reduce the ravages of exotic species of plants. In addition, the overall financial returns on investment for past projects have been excellent, even for the redistribution of agents (see CIE, 2001). It was natural therefore that the Cooperative Research Centre for Australian Weed Management would place particular emphasis on biological control of weeds and organise a workshop to focus its research efforts on improving the science and practice of biological control. These papers discuss only a fraction of the CRC’s work in biological control, but provide an introduction to the research that will continue Australia’s world class contributions to general principles of biological control that can be applied to many other systems. This ranges from improving our understanding of how to conduct host specificity testing more efficiently and reliably (from David Briese and also Tony Willis and colleagues), to approaches and challenges for choosing “winner” agents more effectively in the first place (by Andy Sheppard and also Rachel McFadyen). Evaluation of the successes of biological control is critical not only to improving the practice of biological control, but also to persuading ever-strapped funding sources (who often forget how bad problems were before biocontrol) to stay the course and reinvest in new programs. Such evaluations are critical not only in biological and management terms (as discussed by Dhileepan and by Anthony Swirepik and Matthew Smyth) but also in the economic terms that, by necessity, form the bottom line for decision makers. Tom Nordblom has advanced this case both in his paper here and in his work on the economics of biocontrol of Paterson’s curse for the Weeds CRC (CIE, 2001). Ecological