Response of Orchids to Bushfire Black Saturday Victoria 2009 – Natural values fire recovery program Mike Duncan Response of Orchids to Bushfire Mike Duncan Department of Sustainability and Envrionment Arthur Rylah Institute for Environmental Research 123 Brown Street, Heidelberg, Victoria 3084. This project is No. 27 of the program ‘Rebuilding Together’ funded by the Victorian and Commonwealth governments’ Statewide Bushfire Recovery Plan, launched October 2009. Published by the Victorian Government Department of Sustainability and Environment Melbourne, February 2012 © The State of Victoria Department of Sustainability and Environment 2012 This publication is copyright. No part may be reproduced by any process except in accordance with the provisions of the Copyright Act 1968. Authorised by the Victorian Government, 8 Nicholson Street, East Melbourne. Print managed by Finsbury Green Printed on recycled paper ISBN 978-1-74287-446-3 (print) ISBN 978-1-74287-447-0 (online) For more information contact the DSE Customer Service Centre 136 186. Disclaimer: 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. Accessibility: If you would like to receive this publication in an accessible format, such as large print or audio, please telephone 136 186, 1800 122 969 (TTY), or email customer.service@ dse.vic.gov.au Citation: Duncan, M. (2012). Response of Orchids to Bushfire: Black Saturday Victoria 2009 – Natural values fire recovery program. Department of Sustainability and Environment, Heidelberg, Victoria. Front Cover photograph: Close up of Caladenia orientalis flowers at Wilsons Promontory National Park (Mike Duncan). All photographs in this report are by the author unless otherwise credited. Contents Acknowledgements iv Summary 1 1 Background 2 1.1 The ‘Black Saturday’ 2009 Bushfires 2 1.2 Victoria’s Orchid Flora 2 2 Project Rationale 3 3 Discussion 4 3.1 Fire Killed Species 4 3.2 Fire Sensitive Species 7 3.3 Fire Neutral Species 10 3.4 Fire Stimulated Species 14 3.5 Fire Dependent Species 24 4 Conclusions 27 References 28 Tables i List of figures Figure 1. Sarcochilus australis plant with two flowering spikes (left), and a dead plant following the Kilmore East-Murrindindi Complex South fire (right). Both pictures were taken in Kinglake National Park. 4 Figure 2. Sarcochilus australis habitat in Kinglake National Park nine months (top) and 21 months (bottom) after the Kilmore East-Murrindindi Complex South fire. 5 Figure 3. Thynninorchis huntianus flowers (prior to the Kilmore East-Murrindindi Complex South fire) at a site in Kinglake National Park. No plants of this species have been at this site since the fire. 5 Figure 4. Thynninorchis huntianus habitat in Kinglake National Park (December 2010) following the Kilmore East-Murrindindi Complex South fire. 6 Figure 5. Chiloglottis valida plant that has survived the 2009 bushfire in Wilsons Promontory National Park (November 2010). 6 Figure 6. Acianthus caudatus plant (left), and a seed pod (centre), and an albino Cyrtostylis reniformis plant (right), following the 2009 bushfire in Wilsons Promontory National Park. 7 Figure 7. Corybas diemenicus (left) and C. fimbriatus (right) both flowered in good numbers following the 2009 bushfire in Wilsons Promontory National Park. 8 Figure 8. Corunastylis despectans habitat in Kinglake National Park (October 2009), severely burnt during the Kilmore East-Murrindindi Complex South fire. 9 Figure 9. Flowering in a Pterostylis alveata population prior to the 2009 bushfire in Wilsons Promontory National Park. 9 Figure 10. Close up of a Pterostylis tasmanica flower in Wilsons Promontory National Park following the 2009 bushfire. 10 Figure 11. Pterostylis monticola plants (circled) flowering on the roadside at Lake Mountain (January 2011), following the Kilmore East-Murrindindi Complex North fire. 10 Figure 12. Severely burnt Pterostylis alpina habitat in Mt. Disappointment State Forest (October 2010) following the Kilmore East-Murrindindi Complex North fire. 10 Figure 13. Close up of a Pterostylis chlorogramma flower in Bunyip State Park following the 2009 bushfire. 11 Figure 14. The number of emergent Pterostylis chlorogramma plants prior to and following the 2009 bushfires at Wilsons Promontory National Park and Bunyip State Park. 11 Figure 15. The fate of individual Pterostylis chlorogramma flowers prior to and following the 2009 bushfire at Bunyip State Park, and (to the right of the dashed line) in 2010 at Wilsons Promontory National Park. 12 Figure 16. Monitoring a Pterostylis chlorogramma population in Bunyip State Park (August 2010) following the 2009 bushfire. Some plants are caged. 13 Figure 17. Close up of a Caleana major flower in Won Wron State Forest (left) and a Spiranthes australis flower (right) following the 2009 bushfire. 13 Figure 18. Various orchids that were stimulated to flower following the 2009 bushfire. 15 Figure 19. A close up of a Caladenia praecox plant at Bunyip State Park following the 2009 bushfire. 16 Figure 20. A close up of a Caladenia aurantiaca flower at Wilsons Promontory National Park following the 2009 bushfire. 16 Figure 21. A close up of a Caladenia concolor flower at Mt. Jack State Forest following the Library Road (Beechworth) fire. 16 Figure 22. Department of Sustainability and Environment and Southern Cross University staff monitoring the flowering response of a Caladenia concolor population at Mt. Jack State Forest following the Library Road (Beechworth) fire. 17 ii Figure 23. The number of emergent plants of three Caladenia species prior to and following the 2009 bushfire at Mt. Jack State Forest and Wilsons Promontory National Park. 17 Figure 24. The fate of Caladenia flowers in three populations during spring 2010 (second year since the 2009 bushfire). 18 Figure 25. Uncaged and grazed Caladenia orientalis plants (left), and a caged and fertilised Caladenia orientalis flower, with a developing seed pod (right), in Wilsons Promontory National Park following the Cathedral fire. 19 Figure 26. Elevated view of a fenced Caladenia orientalis population in Wilsons Promontory National Park approximately 8 months (top) and 20 months (bottom) after the Cathedral fire. 19 Figure 27. Impact of grazing on Caladenia orientalis plants in fenced and unfenced permanent plots in Wilsons Promontory National Park during the first two years following the Cathedral fire. 20 Figure 28. A happy orchid enthusiast who was part of a group that found new populations of two Nationally Threatened species, during a search weekend in Wilsons Promontory National Park. 20 Figure 29. A close up of a Prasophyllum odoratum spike (left) and flower (right) in Bunyip State Park following the 2009 bushfire. 21 Figure 30. A close up of a Thelymitra cyanea flower at Lake Mountain following the 2009 bushfire. 22 Figure 31. A close up of a Dipodium roseum flower spike near Marysville following the 2009 bushfire. 22 Figure 32. Mass flowering (left) and a close up of aMicrotidium atratum flower (right) at Bunyip State Park following the 2009 bushfire. 23 Figure 33. Mass flowering (left) and developing seed pods (right) ofPheladenia deformis in Wilsons Promontory National Park following the 2009 bushfire. 24 Figure 34. Close up of a Burnettia cuneata plant in Wilsons Promontory National Park following the Cathedral fire. 25 Figure 35. Pyrorchis nigricans leaves in unburnt forest. 25 Figure 36. Leptoceras menziesii colony in unburnt forest. The colony consists entirely of vegetative plants with small false buds (no flowering individuals). 25 Figure 37. Mass flowering of a Pyrorchis nigricans colony in Wilsons Promontory National Park (September 2009) following the Cathedral fire. 26 Figure 38. Close up of a Leptoceras menziesii plant in Wilsons Promontory National Park (September 2009) following the Cathedral fire. 26 Figure 39. Close up of a Prasophyllum australe flowering spike in Wilsons Promontory National Park (December 2009) following the Cathedral fire. 26 iii Acknowledgements This project is No. 27 of the program ‘Rebuilding Together’ funded by the Victorian and Commonwealth governments’ Statewide Bushfire Recovery Plan, launched October 2009. The author would also like to thank the members of the ANOS (Victorian Group) Conservation Group, Terri Allen, Richard Austin, Anthony Handley, Glen Johnson, Dan Jones, Peter Kiernan, Ed McNabb, Karen Lester, Neil Padbury, Brooke Parfrey, the Promenades Group (Wilsons Promontory), Dean Rouse, Kylie Singleton, Susan Taylor, and Dick Thomson, who have variously supplied site information and/or data, and/or have accompanied the author on field trips. Their contribution has been valuable. In addition, valuable comments about earlier drafts of this report have been made by Claire Moxham and Garreth Kyle. iv Summary This project addresses general community concerns about the response of orchids to the 2009 ‘Black Saturday’ bushfires, by documenting the range of orchid responses encountered across all fire affected areas. The information presented in the report is the result of data synthesis and direct field observations from a variety of sources, collected during the two years since the fires. The response of orchids to the February 2009 bushfires was diverse, spanning the spectrum from being killed