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Submission to the Parliament of Victoria Inquiry into Fire Season Preparedness

Dr Steve Leonard, Prof Andrew Bennett, Dr Angie Haslem, Dr Greg Holland, Dr Simon Watson, Dr Kate Callister, Ms Jemima Connell, Ms Anna Flanagan-Moodie & Prof Mike Clarke

Department of Ecology, Environment & Evolution, La Trobe University, Victoria 3086 Contact: Andrew Bennett

Summary of submission We wish to make recommendations in regard to three of the Inquiry’s Terms of Reference:

a. the amount and nature of preventative burning undertaken to date On the basis of available scientific data, we strongly support the recently adopted risk-based approach to preventative burning (and other fuel reduction measures), based on quantifying and reducing risk to human life and property and to ecological values. We believe this approach is more likely to meet the State’s primary objectives for bushfire management on public land, than a hectare-based target.

d. the impact of preventative burns on threatened species

Fire affects different species in different ways: some are advantaged, some little affected and some are disadvantaged. The primary way in which threatened species of native animals are affected by preventative burning is by its effects on their habitat. Post-fire changes to vegetation and habitat (and to species) extend over many decades. It is essential to investigate and understand the long-term consequences of preventative burning on threatened species. There are many gaps in knowledge.

Our research shows that too frequent, or too extensive and untargeted prescribed burning, has the potential to incinerate critical resources (e.g. hollow logs, hollow-bearing old trees, large clumps of spinifex) essential for the survival and persistence of threatened species.

However, targeted preventative burning in strategic locations can be used to protect important ecological assets and populations of threatened species. The planning for such strategic burning requires detailed knowledge of the location of these key assets, their vulnerability to bushfire, and the effectiveness of preventative burning in reducing risk under various wildfire conditions.

e. the impact of preventative burns on ecological vegetation classes Burning affects different vegetation types in different ways. The ecologically desirable frequency, severity and extent of fires varies among vegetation types and must be taken into account when planning preventative burning – one “size” does not fit all.

Currently, ‘Tolerable Fire Intervals’ used in fire planning are based primarily on the requirements of plant species. We strongly recommend the need to also take into account the responses to fire of animal species and the habitat components they use (e.g. shrub cover, large logs, tree hollows).

We highlight the importance of regional scale planning that identifies the most desirable mix of post-fire age-classes for particular vegetation types, to ensure the resilience of the ecosystem to fire. Our research in different systems (including semi-arid mallee, foothill forests of the Great Dividing Range, box-ironbark forests, and coastal woodlands, forests and heathlands on Wilsons Promontory) has shown the necessity of a deep understanding of how fire affects different ecological vegetation classes.

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1. Background and experience

Collectively, we have undertaken extensive research relating to the ecological effects of fire in south-eastern Australia. We have undertaken major collaborative studies (in partnership with the Dept Environment, Land, Water & Planning; and Parks Victoria) in: - the Murray Mallee region of Victoria, NSW and South Australia - the 2009 Black Saturday fire region in Central Highlands of Victoria - the Box and Ironbark forests of north-central Victoria - the Foothill Forests across southern Victoria. Our research has been published widely in the international scientific literature and we have communicated extensively with land management agencies and the community through presentations and the distribution of thousands of copies of colour information booklets. Further, our research projects have contributed to the training of the next generation of fire ecologists with 10 PhD student completions (to date) and 4 Research Fellows. One of our team leaders, Prof Mike Clarke, was an expert witness in fire ecology at the Victorian Bushfires Royal Commission and in 2014 was invited to participate in an expert panel to evaluate DELWP's response to the Royal Commission’s recommendations in regard to bushfire management.

2. Response to the Terms of Reference Terms of Ref 1a: the amount and nature of preventative burning undertaken to date The Code of Practice for Bushfire Management on Public Land (2012) identifies two primary objectives for bushfire management on public land:

1. To minimise the impact of major bushfires on human life, communities, essential and community infrastructure, industries, the economy and the environment. Human life will be afforded priority over all other considerations.

2. To maintain or improve the resilience of natural ecosystems and their ability to deliver services such as biodiversity, water, carbon storage and forest products.

We strongly support the recently formulated risk-based approach to fire management (Department of Environment and Primary Industries 2013a) as a more effective means of protecting people and assets than burning to achieve an annual hectare-based target. A risk-based approach also gives land managers greater scope to use fire for ecological purposes.

It is well recognised that the characteristics of vegetation fuels (e.g. fuel load and configuration) affect fire behaviour (Sullivan et al. 2012). Reducing fuel loads by planned burning (or other means) can reduce the intensity and rate of spread of bushfires (McCaw 2013). However, the idea that more planned burning necessarily means less risk from bushfires, while intuitively appealing, is simplistic.

a) A critical factor is the location and spatial configuration of planned burns relative to the assets they are intended to protect. For example:

In relation to the 2009 Black Saturday fires, Gibbons et al. (2012) found that the “proximity to houses of prescribed burning is more important than the total percentage of the landscape that is prescribe-burnt”.

In Tasmania, in relation to using planned burning to protect ecological assets, King et al. (2006) found that burning 3% of buttongrass moorland in a strategic configuration was likely to reduce the area of fire-sensitive alpine vegetation burnt annually by the same amount as burning ≥ 10% of moorland in a random or deterministic pattern.

Thus, a key issue relating to preventative burning is that it is not necessarily the amount of burning that reduces risk, but where it is applied. We support an approach based on applying planned burning where it is demonstrated that it will have greatest benefit in reducing risk to life, property and ecological assets.

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b) The primary evidence that an increased area of planned burning is correlated with reduced extent of bushfire comes from eucalypt forests of south-western Western Australia (Boer et al. 2009). It is notable that while extensive planned burning is undertaken in these forests, there is not a blanket application of planned burning in other vegetation types and regions across Western Australia – such as woodlands, mallee shrublands or heathlands. Further, the effectiveness of planned burning in limiting bushfire extent in Western Australian forests may be enhanced by the more subdued topography, greater number of days when planned burning is feasible, and generally less severe fire weather in WA compared with Victorian forested regions (Teague et al. 2010).

c) Planned burning is logistically intensive and expensive. In Victoria, there are relatively few days when weather conditions allow safe application of planned burning (as few as 10 per year; Esplin et al. 2003). It is important that resources and opportunities for planned burning are directed where they will bring about maximum benefit in terms of risk reduction.

The previous area-based target of 5% of public land annually meant that land managers carried out large planned burns to meet this top-down target, even though the resulting risk reduction may be limited. Large planned burns in remote areas where few people live (e.g. the Mallee region) do little to increase the overall safety of the Victorian community, but do have the potential to do ecological harm (see below). Data presented in reports by the Department of Environment, Land Water and Planning on recent planned burning indicate the bulk of burning was not occurring in areas where the greatest risk to life and property lies (Department of Environment and Primary industries 2013b, 2014). To summarise:

68% of the state-wide risk to life and property lies in an arc surrounding the Greater Melbourne and Geelong region (East Central, West Central and Barwon Otway Bushfire Risk Landscapes)

The majority of planned burning in 2012-13 & 2013-2014 occurred in remote areas, outside these regions.

The Mallee region represents just 2-3% of the State’s risk to life and property, mostly relating to towns distant from large reserves in the region. However, 17-20% of planned burning in Victoria in 2012-13 and 2013-14 occurred in the Mallee region, mostly in the large reserves (Figure 1).

Figure 1. The estimated percentage of state-wide risk to life and property (blue) in the Mallee Murray Goulburn region compared to the percentage of the State’s total planned burning carried out in the Mallee Loddon region 2012-2013 (orange) and 2013-2014 (red). Source of data: Department of Environment and Primary Industries (2013) Victorian Bushfire Risk Profile Report, Department of Environment and Primary Industries (2013) Reducing Victoria’s Bushfire Risk on Public Land Fuel Management Report 2012-2013, Department of Environment and Primary Industries (2014) Reducing Victoria’s Bushfire Risk on Public Land Fuel Management Report 2013-2014). Note: regional boundaries used in the Risk Profile Report and the Fuel Management Reports differ. However, the data presented in this figure are likely to be an underestimate of the proportion of the state’s total planned burning that occurred in the Mallee.

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burning while such gaps remain. There is a clear need for a strategic program of research targeted to address knowledge gaps in priority ecosystems across the state.

Terms of Ref. 1e - the impact of preventative burns on ecological vegetation classes

We highlight three important issues concerning the impact of preventative burns on ecological vegetation classes. a) First, a fundamental issue is that fire (bushfire and planned burns) affects different vegetation types in different ways. There is great variation in their flammability, their risk of ignition, and the response of plant communities to fire. For example, the minimum tolerable fire interval after low severity fire, as recommended by the (former) Department of Sustainability and Environment (Cheal 2010), is 2 years for Basalt Grassland, 10 years for Heathy Dry Forest and Foothills Forest, 25 years for Moist Forest and Hummock Grass Mallee, 40 years for Saltbush Mallee and 80 years for Tall Mist Forest and Closed Forest.

These differences between vegetation types must be taken in to consideration when planning regional strategies for preventative burning, especially relating to the frequency of burns, severity of burns and the spatial arrangement of burns (size, patchiness). It is not a case of ‘one size fits all’. b) Second, changes to vegetation and the habitats they provide for native fauna extend for many decades after burning. ‘Tolerable Fire Intervals’, commonly used in fire planning, are based primarily on plants and their ability to persist in the environment; such as the minimum time required post-fire for plants to mature and set seed. They do not make allowance for the time required to replace habitat components for animals, such as dense shrub cover, tree hollows, deep leaf litter and large logs. Consequently, the ‘Minimum Tolerable Fire Interval’ based on plant requirements is not a suitable measure for determining the frequency of fire for an ecosystem. Planning for burning must take account of the responses of all components of an ecosystem and how they recover after fire.

For example, our work in semi-arid mallee ecosystem demonstrated that changes in habitat resources such as spinifex clumps, tree cover, litter cover and tree hollows continue for many decades after fire (Haslem et al. 2011). Correspondingly, many faunal species favour older vegetation, at least 20-40 years since last fire and even older. Species that use large spinifex clumps (Triodia) such as many reptiles, the small marsupial Mallee Ningaui and the endangered Mallee Emu-wren (Stipiturus mallee), are more likely to occur in vegetation of 20-40 years post-fire, which coincides with the peak in spinifex cover. Tree hollows, another important habitat feature (e.g. for many birds and bats) are also much more abundant in long-unburnt mallee vegetation, only beginning to develop at least 40 years after the last fire but destroyed by repeated fires at shorter intervals (Haslem et al. 2011).

c) Third, given the differences between vegetation types and that changes after fire extend for many decades, we strongly advocate the need for regional-scale planning that identifies the most suitable mix of post-fire age-classes necessary to maintain ecological values and to ensure the resilience of the system to fire. Preventative burning can then be undertaken within this context, with much greater confidence that it can reduce risk to human life and property without compromising other values that society recognises.

We have demonstrated, for the mallee ecosystem, that a desirable mix of age classes can be determined (Kelly et al. 2014). However, for many other vegetation types such knowledge is still lacking. Further work is needed to determine the extent and spatial configuration of age-classes that will best enhance the resilience of plant and animal plant communities in major vegetation types across the state. References

Avitabile S (2014). Mallee HawkEye Project: Final Report. La Trobe University, Melbourne.

Avitabile S. C., Callister K. E., Kelly L. T., Haslem A., Fraser L., Nimmo D. G., Watson S. J., Kenny S. A., Taylor R. S., Spence-Bailey L. M., Bennett A. F. and Clarke M. F. (2013) Systematic fire mapping is critical for fire ecology,

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planning and management: A case study in the semi-arid Murray Mallee, south-eastern Australia. Landscape and Urban Planning 117:81-91.

Boer MM, Sadler RJ, Wittkuhn RS, McCaw L, Grierson PF (2009) Long-term impacts of prescribed burning on regional extent and incidence of wildfires—evidence from 50 years of active fire management in SW Australian forests. Forest Ecology and Management 259, 132-142.

Cheal D (2010) Growth stages and tolerable fire intervals for Victoria’s native vegetation data sets. Fire and Adaptive Management Report No. 84. Department of Sustainability and Environment, East Melbourne, Victoria, Australia.

Connell J, Taylor RS, Watson SJ, Avitabile SC, Schedvin N, Bennett AF, Clarke R, Clarke MF (in prep a) Distribution of threatened Mallee birds with relation to post-fire age. Appendix 6, Avitabile S (2014). Mallee HawkEye Project: Final Report. La Trobe University, Melbourne.

Connell J, Taylor RS, Avitabile SC, Watson SJ, Schedvin N, Schneider K, Bennett AF, Clarke MF (in prep b). Predicting the impact of future planned burning on a suite of threatened Mallee bird species. Appendix 8, Avitabile S (2014). Mallee HawkEye Project: Final Report. La Trobe University, Melbourne.

Department of Environment and Primary Industries (2013a) Victorian Bushfire Risk Profiles. Victorian Government, Melbourne.

Department of Environment and Primary Industries (2013b) Bushfire Risk on Public Land. Fuel Management Report 2012–13. Victorian Government, Melbourne.

Department of Environment and Primary Industries (2014) Bushfire Risk on Public Land. Fuel Management Report 2013–14. Victorian Government, Melbourne.

Department of Sustainability and Environment (2012) Code of Practice for Bushfire Management on Public Land. Victorian Government, Melbourne.

Esplin, B., Gill, M. and Enright, N. (2003), Report of the Inquiry into the 2002-2003 Victorian Bushfires. Victorian Government, Melbourne

Gibbons P, van Bommel L, Gill AM, Cary GJ, Driscoll DA, Bradstock RA, Knight E, Moritz MA, Stephens SL, Lindenmayer DB (2012) Land management practices associated with house loss in wildfires, PLoS ONE 7(1), e2912.

Giljohann KM, McCarthy MA, Kelly LT, Regan TJ (2015) Choice of biodiversity index drives optimal fire management decisions. Ecological Applications 25, 264-277.

Haslem A, Kelly LT, Nimmo DG, Watson SJ, Kenny SA, TaylorRS, Avitabile SC, Callister KE, Spence-Bailey LM, Bennett A F, Clarke MF (2011) Habitat or fuel? Implications of long-term, post-fire dynamics for the development of key resources for fauna and fire, Journal of Applied Ecology, 48, 247-256.

Holland, G.J. (2015). Box-Ironbark Experimental Mosaic Burning Project. Unpublished report to the Department of Environment, Land, Water and Planning, and Parks Victoria, Melbourne.

Kelly, L.T., Bennett, A.F., Clarke, M.F. and McCarthy, M. 2015. Optimal fire histories for biodiversity conservation.

Conservation Biology 29: 473-481.

King KJ, Cary GJ, Bradstock R, Chapman J, Pyrke AF, Marsden-Smedley JB (2006). Simulation of prescribed burning strategies in south west Tasmania, Australia: effects on unplanned fires, fire regimes and ecological management values. International Journal of Wildland Fire 15, 527-540.

McCaw WL (2013). Managing forest fuels using prescribed fire: a perspective from southern Australia. Forest Ecology and Management 294, pp. 217–224

Sullivan AL, McCaw WL, Cruz MG, Matthew S, Ellis PF (2012). Fuel, fire weather and fire behaviour in Australian ecosystems. In Flammable Australia: Fire Regimes, Biodiversity and Ecosystems in a Changing World (eds RA Bradstock, AM Gill, RJ Williams). CSIRO Publishing, Collingwood. pp. 51–77

Teague B, McLeod R, Pascoe P (2010) 2009 Victorian Bushfires Royal Commission: Final Report. Parliament of Victoria, Melbourne.

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