Mountain Ash: Fire, Logging and the Future of Victoria's Giant Forests

By David Lindenmayer, David Blair, Lachlan McBurney and Sam Banks

Mountain Ash draws together exciting new findings on the effects of fire and on post-fire ecological dynamics following the 2009 wildfires in the Mountain Ash forests of the Central Highlands of Victoria. The book integrates data on forests, carbon, fire dynamics and other factors, building on 6 years of high-quality, multi-faceted research coupled with 25 years of pre-fire insights.

Topics include: the unexpected effects of fires of varying severity on populations of large old trees and their implications for the dynamics of forest ecosystems; relationships between forest structure, condition and age and their impacts on fire severity; relationships between logging and fire severity; the unexpectedly low level of carbon stock losses from burned forests, including those burned at very high severity; impacts of fire at the site and landscape levels on arboreal marsupials; persistence of small mammals and birds on burned sites, including areas subject to high-severity fire, and its implications for understanding how species in this group exhibit post-fire recovery patterns.

With spectacular images of the post-fire environment, Mountain Ash will be an important reference for scientists and students with interests in biodiversity, forests and fire.

• Language: English
• Publisher: CSIRO PUBLISHING
• Release date: Nov 2, 2015
• ISBN: 9781486304998

Book preview

MOUNTAIN ASH

We dedicate this book to all those people who have worked so hard for so long to better protect the extraordinary natural environments that make Australia such a beautiful and amazing place.

For the late Pam Miskin, whose dedication to threatened species was matched with her love of teaching others about them.

MOUNTAIN ASH

Fire, Logging and the Future of

Victoria’s Giant Forests

David Lindenmayer, David Blair, Lachlan McBurney and Sam Banks

With contributions from Philip Barton, Laurence Berry, Wade Blanchard, Emma Burns, Mason Crane, Ross Cunningham, Dan Florance, Phil Gibbons, Heather Keith, Peter Lane, Christopher MacGregor, Damian Michael, Sachiko Okada, Thea O’Loughlin, Emma Pharo, Stephanie Pulsford, Annabel Smith, John Stein, Nici Sweaney and Jeff Wood.

© David Lindenmayer 2015

All rights reserved. Except under the conditions described in the Australian Copyright Act 1968 and subsequent amendments, no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, duplicating or otherwise, without the prior permission of the copyright owner. Contact CSIRO Publishing for all permission requests.

National Library of Australia Cataloguing-in-Publication entry

Lindenmayer, David, author.

Mountain ash : fire, logging and the future of Victoria’s giant forests / David Lindenmayer, David Blair, Lachlan McBurney and Sam Banks.

9781486304974 (paperback)

9781486304981 (epdf)

9781486304998 (epub)

Includes bibliographical references and index.

Eucalyptus regnans – Victoria.

Eucalyptus regnans – Effect of fires on – Victoria.

Forest fires – Environmental aspects – Victoria.

Logging – Victoria.

Blair, David P., author.

McBurney, Lachlan, author.

Banks, Sam C., author.

583.76609945

Published by

CSIRO Publishing

Locked Bag 10

Clayton South VIC 3169

Australia

Telephone: [phone]

Email: [e-mail]

Website: www.publish.csiro.au

Photographs by David Blair unless otherwise noted.

Front cover: (top) Mountain Ash forest (David Blair);

(bottom) Post-fire salvage logging (Lachlan McBurney)

Back cover: Leadbeater’s Possum (Steve Kuiter)

Set in 10/14 Palatino

Edited by Peter Storer Editorial Services

Cover design and typeset by James Kelly

Index by Bruce Gillespie

Printed in China by 1010 Printing International Ltd

CSIRO Publishing publishes and distributes scientific, technical and health science books, magazines and journals from Australia to a worldwide audience and conducts these activities autonomously from the research activities of the Commonwealth Scientific and Industrial Research Organisation (CSIRO). The views expressed in this publication are those of the author(s) and do not necessarily represent those of, and should not be attributed to, the publisher or CSIRO. The copyright owner shall not be liable for technical or other errors or omissions contained herein. The reader/user accepts all risks and responsibility for losses, damages, costs and other consequences resulting directly or indirectly from using this information.

Original print edition:

The paper this book is printed on is in accordance with the rules of the Forest Stewardship Council®. The FSC® promotes environmentally responsible, socially beneficial and economically viable management of the world’s forests.

FOREWORD

Our precious forests are among the most important ecosystems on earth. They provide habitat for vast numbers of species, supply drinking water for humans, and store enormous quantities of carbon that is critical for tackling dangerous climate change.

This wonderful book by David Lindenmayer and many of his scientific colleagues from The Australian National University highlights the array of critical values of the Mountain Ash forests of Victoria – the world’s tallest flowering plants. The book is based on six years of intensive research that has taken place since the ‘Black Saturday’ wildfires in 2009, which, I am told, were the most destructive fires in Australian history in terms of loss of life and property.

I understand that the past six years’ work was built on more than 25 years of painstaking forest ecological research, making it some of the longest, continuously running forest research of its type in Australia and elsewhere around the world.

The research summarised in this book provides solid scientific arguments as to why it is so important to protect Victoria’s magnificent Mountain Ash forests, not only for conserving critically endangered animals like Leadbeater’s Possum but also to protect carbon stocks, water supplies and emerging eco-tourism industries.

I strongly commend this book to anyone concerned about maintaining the many important natural values of forests.

Jane Goodall PhD, DBE,

Founder – the Jane Goodall Institute

& UN Messenger of Peace

CONTENTS

FOREWORD

PREFACE

ACKNOWLEDGEMENTS

1.  GENERAL INTRODUCTION

How this book was written

The structure of the book

Background scientific articles

Common and scientific names

Caveats

2.  THE 2009 BLACK SATURDAY FIRES

Introduction

Key questions

The importance of commencing work immediately after fire

Fire severity and past disturbance history

Landscape traps

Extra work to be done and knowledge gaps to be filled

Lessons learned and management implications

3.  THE FOREST AND ITS PLANTS

Introduction

The flora of montane ash forests

Key questions

When is a tree ‘mature’ and when does it develop hollows?

Historical perspectives on old growth forest

Post-fire regeneration of montane ash forest

The response of mosses and lichens to fire

The effects of fire, logging and salvage logging on tree ferns

Extra work to be done and knowledge gaps to be filled

Lessons learned and management implications

4.  LARGE OLD TREES AND THE 2009 FIRES

Introduction

Key questions

Fire, drought and populations of large old hollow-bearing trees

Projections of the future abundance of large old hollow-bearing trees

Large old hollow-bearing trees and the status of old growth forest

Extra work to be done and knowledge gaps to be filled

Lessons learned and management implications

5.  CARBON STOCKS

Introduction

Key questions

Carbon stocks in montane ash forests

The effects of wildfire on carbon stocks

Forest carbon stocks and logging

Extra work to be done and knowledge gaps to be filled

Lessons learned and management implications – carbon emissions abatement, logging operations and plantation timber

6.  THE RESPONSE OF POSSUMS AND GLIDERS TO FIRE

Introduction

Key questions

Fire and arboreal marsupials

Fire refugia and arboreal marsupials

The special case of fire and the Mountain Brushtail Possum

Population Viability Analysis – assessing the effectiveness of the reserve system for Leadbeater’s Possum

Extra work to be done and knowledge gaps to be filled

Lessons learned and management implications

7.  SMALL TERRESTRIAL MAMMALS

Introduction

Key questions

Post-fire recovery in small terrestrial mammals

Extra work to be done and knowledge gaps to be filled

Lessons learned and management implications

8.  THE RESPONSE OF BIRDS TO FIRE

Introduction

Key questions

Fire effects on birds in montane ash forests

The effects of prior occurrence on post-fire occurrence

Extra work to be done and knowledge gaps to be filled

Lessons learned and management implications

9.  THE RESPONSE OF INVERTEBRATES TO FIRE

Introduction

Key questions

The responses of beetles to fire

Extra work to be done and knowledge gaps to be filled

Lessons learned and management implications

10. MANAGING A POST-FIRE FOREST LANDSCAPE

Introduction

Forest restoration strategies

Key objective 1 – Conserve existing important structures, habitats and other key areas

Key objective 2 – Restore and expand populations of key species and key structures, restore patterns of old growth landscape cover and restore key ecosystem processes

Key objective 3 – Restore key ecosystem processes

An expanded National Park as a key part of forest restoration in montane ash forests

Positive interactions and co-benefits of a suite of forest restoration strategies

Priority actions

Altered logging regimes as part of forest restoration

Extra work to be done and knowledge gaps to be filled

Concluding remarks

11. THE FUTURE

Introduction

The critical value of long-term research and monitoring

The importance of forest reform

Montane ash forests and climate change

An alternative vision for montane ash forests

The importance of ongoing monitoring and its link to environmental accounts

Future work

Concluding remarks

REFERENCES

APPENDIX – COMMON AND SCIENTIFIC NAMES OF SPECIES MENTIONED IN THIS BOOK

INDEX

PREFACE

It is more than 6 years since we commenced our research on the response of animals and plants to the tragic and highly destructive 2009 Black Saturday wildfires in the wet montane ash forests of Victoria – the worst fires in Australian history in terms of loss of human life and damage to property. Our post-fire work was preceded by 25 years of detailed research before the fires.

We wrote a short book immediately following the 2009 fire – Forest Phoenix: How a Great Forest Recovers After Wildfire. In it, we speculated about how different plants and animals might respond to that horrific conflagration. Since then we have made many discoveries, some unexpected. Numerous people have asked us about what has been happening in the forests. It was therefore time to update the story and to report some of our discoveries about the state of the forests and the plants and animals they contain (or used to contain). It also was time to produce a synthesis of new information across the array of different areas of research we have conducted since the fires.

Our book spans many topics, ranging from forest carbon stocks to the responses of beetles to wildfire. This array of topics has made the book longer and more complex than its predecessor, Forest Phoenix. However, it is a richer and more fascinating journey and one that we hope many readers will find interesting and informative.

The authors

June 2015

Why is material on logging in a book about post-fire forest recovery?

Much of this book describes studies of post-fire ecological recovery. But we have also elected to include considerable scientific material on logging (see Chapter 10) for several reasons. First, there is now compelling empirical evidence that logging history and fire dynamics are intimately intertwined.¹ Second, given the extent of past logging and past and recent fire, the future of species such as Leadbeater’s Possum and even the forest itself following the 2009 fires depends on major reforms to forest management, particularly the amount of clearfell logging that takes place.²,³ Indeed, the forest management decisions made now will have significant (positive or negative) implications for montane ash forests for decades and even centuries into the future.

ACKNOWLEDGEMENTS

The history of our work in the wet forests of Victoria dates back more than three decades – it started in the middle of 1983. Literally thousands of people have made our work possible.

The research summarised in this book would not have been possible without the extraordinary efforts of a truly talented and world-class group of expert statistical scientists at The Australian National University – Ross Cunningham, Jeff Wood, Alan Welsh, Wade Blanchard, Philip Tennant and Peter Lane.

We thank many outstanding scientific colleagues with whom we have worked closely on key topics and issues in the montane ash forests of Victoria for many years. Several need special mention for their contributions: Christine Donnelly, Malcolm Gill, Richard Hobbs, Jerry Franklin, Karen Ikin, Charles Krebs, Robert Lacy, Bill Laurance, Gene Likens, Mike McCarthy, Brendan Mackey, David Meagher, Henry Nix, Hugh Possingham and Chris Taylor.

Funding to maintain the scientific research in the Central Highlands of Victoria has come from many sources. These include the Australian Research Council, the National Environmental Research Program (NERP), the Terrestrial Ecosystem Research Network (TERN), the Victorian Department of Environment and Primary Industries, Parks Victoria, Melbourne Water, Fujitsu Laboratories Limited and The Thomas Foundation. We are most grateful to all of these organisations for their generous support and collaboration.

Part of our work in the Victorian forests has focused on possums and gliders, including the iconic Leadbeater’s Possum. The night-time field survey component of that research has required the assistance of thousands of volunteers over the past 32 years. We have never kept a register of all these wonderful volunteers who braved cool nights, mosquitoes and leeches to help find and count animals. We know that some, such as Paul Jones, have assisted in field surveys for more than a decade! Perhaps, in retrospect, we should have made that list of volunteers, so we could gratefully acknowledge each and every person. But in truth we never anticipated that we would still be working three decades after the research commenced! Irrespective of this oversight on the part of one of us (DBL), we would like to thank all the volunteers who have assisted in the work in the Central Highlands of Victoria over the past three decades.

We extend special thanks to Sarah Rees, Steve Meacher and the Friends of Leadbeater’s Possum for their unstinting work to save these iconic forests.

We thank the outstanding staff from CSIRO Publishing, an organisation that has helped produce so many wonderful books over many, many years. The support of John Manger and Tracey Millen in completing this particular book is most gratefully acknowledged.

All books, even a short one, are never easy to write. They also don’t materialise without assistance from dedicated support staff. In particular, we thank Claire Shepherd, Tabitha Boyer and Clive Hilliker for expert editing and graphics assistance.

The authors

June 2015

August 2009

Tree ferns are the ultimate survivors, even in forest burned at very high severity like the stand in this image. This means that old growth tree ferns exceeding hundreds of years old can persist in forests where the overstorey eucalypts may be just 20-30 years old.

December 2012

July 2009

This stand burned at low severity in 2009, but all the large old trees (numbered in white paint) were nevertheless destroyed and rendered unsuitable as nest sites for hollow-using animals.

April 2010

March 2010

Intensive post-fire salvage logging significantly alters the structure of montane ash forest. There are no large old trees in these forests and hence no cavity-dependent animals; the dead standing trees in the background were young regrowth that regenerated after logging about 20 years ago. Plant species richness in this area is half what is found in other burned locations that were not salvage logged.

July 2012

December 2009

This area of old growth forest burned at high severity but the young forest that regenerated after the 2009 fire is growing rapidly; in just over 4 years that elapsed between these two photos, it had grown six metres.

March 2014

Natural icon. Montane ash forests are one of the world’s iconic forest ecosystems. They support magnificent tall trees, store vast amounts of carbon, provide habitat for many plants and animals, provide most of Melbourne’s water and have huge, currently untapped, tourism potential. This image shows a stand of trees that regenerated after the Black Friday wildfires that burned the area in 1939. This stand regenerated from seed that fell from the burned canopies following the fires. The 1939 aged forests are still the most widespread of the intact forest age classes in the Central Highlands of Victoria. How these forests are managed will have a profound impact on biodiversity, water supplies, fire behaviour and tourism. This book aims to summarise some of the large and rapidly expanding body of science designed to help inform policy making and management in montane ash forests.

CHAPTER 1

GENERAL INTRODUCTION

Our research team in the Fenner School of Environment and Society at The Australian National University (ANU) has been working in the montane ash forests of Victoria for more than 30 years (see Figs. 1.1 and 1.2). The 2009 wildfires in these forests were a time of great sadness as friends and colleagues lost their lives in the fires, while others who survived lost their property. However, the fires also provided a truly unique opportunity to answer some important questions about the ecology of forest fires, in particular how plants and animals respond to such a major disturbance. This opportunity was strengthened by 25 years of high-quality scientific information that we collected before the fire throughout the ash forests, including an array of study sites unaffected by the fires that we could use as ‘controls’ or comparison sites. As a result, the 2009 fires have provided extremely valuable ecological insights and, in doing so, improved our understanding of how to manage these forests for the future. Indeed, we were very fortunate to be able to re-commence work on our long-term study sites within 4 weeks of the fires and detailed studies have continued since then. This research has explored not only the patterns of animal and plant occurrence, but also, in many cases, has revealed some of the key ecological processes giving rise to those patterns.

Many of our new findings were highly unexpected, such as the widespread mortality of living trees during the drought in the 2000s, the sensitivity of animals such as the endangered Leadbeater’s Possum to fire,⁴ how past logging operations can make forests more prone to burning at high severity,¹ and very limited losses of carbon despite the 2009 fire being one of the most severe fires ever recorded.⁵,⁶ Given how much has been learned in the 6 years that have elapsed since the 2009 fires, we strongly believed that it was important to share these discoveries with a broad audience. Hence the writing of this book.

The 2009 fires were far from being a unique event in the wet forests of Victoria – previous large fires have occurred in these forests in 1824, 1851, 1926, 1932, 1939 and 1983. Less extensive conflagrations occurred in 1895, 1905, 1908, 1918, 1948, 1962 and 2014. At the time of the last major fire in the Central Highlands of Victoria (1939), the discipline of ecology had only just emerged: one of the earliest ecological papers published worldwide was actually from the Black Spur area near Healesville.⁷ It was therefore not really possible to learn then about the ecological effects of the 1939 fires in a scientific way. The 2009 fires were clearly very different. Ecology is now a major and well-established discipline, making it possible to use the existing body of ecological knowledge, together with the new discoveries from ongoing work, to develop a new understanding of forest ecology that is not only critical for the Central Highlands region and Victoria, but also globally. This understanding ranges from the impacts and behaviour of the fire itself⁸ to changes in populations of organisms such as large old trees – an issue that has worldwide implications, but which has been best documented in Victoria by the ANU team and the authors of this book.⁹

One of the strengths of the approach that the ANU team has taken is that it spans many different facets of work. This allows important cross-fertilisation between different strands – such as fire effects on large old trees and, in turn, the impacts of losses of these large old trees on populations of cavity-dependent animals that depend on such trees¹⁰ (Chapter 6), as well as losses in carbon stocks from burned forests⁶ (Chapter 5).

Figure 1.1. Location map of Central Highlands of Victoria.

How this book was written

This book was written conjointly by long-term researchers, field ecologists based permanently in the forest, professional statisticians and an exciting group of (mostly) young postgraduate scientists. All are from the Fenner School of Environment and Society at The Australian National University in Canberra. Many of us spend prolonged periods of time working together in the field and this provides a wonderful environment to develop new ideas, and discuss the content of new scientific articles and books.

Most of photographs were taken by David Blair, who is one of the two field ecologists working full-time in the wet forests of Victoria (the other is Lachlan McBurney). The book has several sets of photographs taken at the same place but at different times. This approach is a powerful way to illustrate how montane ash forests have changed over time, including after fire.

The structure of the book

This book comprises a series of short chapters, each of which is characterised by a limited amount of text but richly illustrated by photographs. Each photograph is accompanied by an informative caption giving additional commentary on the ‘story’ depicted in the image. In this way, we have aimed to connect both with readers who will read the book sequentially from cover to cover and others who might ‘dip into’ the book by looking mostly at the images.

Part of this book concerns documenting how particular groups of animals and plants have responded to the 2009 fire. An associated aim has been to determine why particular groups have responded in the way they have by identifying the mechanisms driving changes over time. However, as part of this work, we have also discovered a lot about fire itself. Therefore, parts of the next chapter (Chapter 2) include summaries of work on fire severity and how it is influenced not only by fire weather, but also by prior disturbances such as logging.¹ In Chapter 3 we explore the response of the forest and the vegetation to fire. Large old trees are a key structural component of the vegetation in montane ash forests and have been a focus of our research since 1983. We have therefore dedicated an entire chapter to summarising post-fire research on large old hollow-bearing trees (Chapter 4). Chapter 5 focuses on the effects of fire on carbon stocks in montane ash forests – a key topic given that stands of old growth montane ash forests are the most carbon-dense terrestrial ecosystems on the planet.¹¹

Figure 1.2. Map of the locations of the ecological vegetation classes that correspond to montane ash forests.

Chapters 6 to 9 discuss some of the impacts of the 2009 fire on different groups of animals and plants, with a particular focus on patterns of post-fire ‘recovery’. We have put quotation marks around the term ‘recovery’ in this context because some species were in fact not markedly affected by the 2009 fire and populations of others (such as the Flame Robin) pulsed strongly (and positively) directly after it.¹² Therefore, the term ‘recovery’ is misleading and inappropriate for these kinds of organisms.

Chapter 10 provides an overview of our work on managing the forest estate after the 2009 fires. This is an important part of