Fuel management planning for the protection of multiple forest values: the Leadbeater’s Possum and water catchments

Our fuel management strategies are designed to consider impacts on multiple forest values through the operational delivery of any fuel management activities. Planning and delivery of this work is undertaken with input by internal and external experts to ensure forests are managed for a diverse range of ecological, cultural and built values. In the Port Phillip region, this includes considering the critically endangered Leadbeater’s Possum and key water catchment areas in their risk reduction strategies.

Leadbeater’s Possum

The Leadbeater’s Possum is endemic to the State of Victoria and is highly valued as our faunal emblem. The species is listed as a critically endangered at both the State and Commonwealth levels, with fire being one of its major threats. As such, Forest Fire Management Victoria (FFMVic) places paramount importance on undertaking planning to protect this species. 

The Leadbeater’s Possum population is largely confined to an area of approximately 70 by 80 kilometres within ash forests of the Central Highlands north-east of Melbourne. Leadbeater’s Possum are forest-dependent, prefer older tree age classes in moist forest types and are obligate users of hollow-bearing trees for shelter and nesting. 

Concern for Leadbeater’s Possum increased significantly after the 2009 bushfires, which burnt around 45% of the area reserved specifically for the species. This fire has intensified ongoing habitat decline caused by the collapse of dead nesting trees that were left standing after the 1939 bushfires. This loss of hollow-bearing trees is predicted to lead to a bottleneck in suitable habitat, and thus also the population of Leadbeater’s Possum, over the next 70 years, increasing the risk of the species’ extinction. Future bushfires further exacerbate this risk. 

FFMVic recently explored the development of a fuel management strategy to protect the Leadbeater's Possum from the risk of bushfire, in line with recommendation 8.2 of the Leadbeater's Possum Advisory Group Recommendations report. The recommendations are aimed at slowing the projected decline in population numbers in the Central Highlands within the broader context of the timber industry to help ensure there are enough individuals for the species to recover once it passes through the habitat bottleneck. Using Phoenix modelling approaches, FFMVic staff identified areas for targeted fuel management that would have the greatest potential to reduce bushfire risk to the possum.

Expanding to water values

In consultation with Melbourne Water and the University of Melbourne, the project was expanded to include consideration of water values within catchment areas that overlap significantly with the distribution of the Leadbeater’s Possum habitat. Catchment areas are vulnerable to major bushfire events and may also benefit from bushfire protection efforts such as fuel management. This project also provided opportunity to review some areas currently zoned for fuel reduction. This work aimed to realign the fire management zones to support bushfire risk reduction activities to protect water quality and yield. These activities focussed on: minimising debris flows that reduce the quality of the water is due to ash, debris and erosion incursion into storages; and increasing water yield through maintaining mature vegetation, which allows greater water infiltration into storages compared to recovering and regenerating vegetation, so the amount of water that flows to the reservoirs is reduced. 

By quantifying the cost of fuel management to multiple forest values, FFMVic staff were able to evaluate the costs with the benefits of a range of fuel management strategy options to conserve Leadbeater’s Possum and water assets in catchment areas downstream of identified fuel management areas to best account for multiple forest values in development of the strategy.

Page last updated: 23/12/20