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Biophysical Units for Fire Management

For the Greater Grampians Landscape Management Unit Fire Ecology Strategy

June 2009

Centre for Environmental Management

Biophysical Units for Fire Management

For the Greater Grampians Landscape Management Unit Fire Ecology Strategy

June 2009

Prepared for Parks Victoria by:

Centre for Environmental Management, University of Ballarat

Authors: Grant Palmer Sara Munawar

Executive summary

Parks Victoria commissioned this project to identify options for biophysical units within the Greater Grampians Landscape Management Unit (GGLMU). The primary aim of this project is to identify options for biophysical units based on a review of ecological factors and to provide the rationale and implications of these options for the Greater Grampians.

To this end, the project considered the following:

What are the broad ecological boundaries across the Greater Grampians landscape?

What are the main landscape features / species / habitat types / Ecological Vegetation Classes / Ecological Vegetation Divisions that influence and form these boundaries?

What are the known fire regimes of the key landscape features / species / habitat types / Ecological Vegetation Classes / Ecological Vegetation Divisions/ that influence and form these boundaries

The following definition of biophysical units was considered appropriate for this project.

"A Biophysical Unit is a planning unit bounded by landscape factors be they physical or physiological or driven by species habitat preferences that potentially limit species movement or dispersal through the landscape, effectively creating independent units (meta-population model)."

Biophysical units in the Greater Grampians will be used by land and fire managers as the base scale for setting desired medium and long term outcomes for specific ecological values that are potentially most impacted on by fire. Importantly, the biophysical units are considered an integrated set and combined they form a connected landscape across the Greater Grampians LMU.

A set of nine flora species suitable for use as a Key Fire Response Species within the GGLMU were determined using the Key Fire Response Level developed by Cheal (under review) for species recorded in the Greater Grampians LMU. Twenty-two potential fauna KFRS were selected for the GGLMU based on criteria including the fire response of the species was known, the species displayed a strong association with particular seral-stages and the species was easily monitored.

Landscape factors that were considered to provide potential ecological boundaries in the Greater Grampians LMU included the linear rocky escarpment (e.g. Victoria Range, Mt William Range) and reservoirs (e.g. Rocklands Reservoir) and major streams (e.g. Glenelg River). These boundaries were then overlayed onto catchment, watershed, bioregions and vegetation maps to identify potential biophsyical units.

A total of 15 biophysical units were identified within the Greater Grampians Landscape Management Unit, based on catchment and watershed mapping, the presence of ecological vegetation divisions and endemic ecological vegetation classes, and the presence of physical barriers to small mammal movement (e.g ridge lines).

The biophysical units identified in this project provide a base scale to be used by land and fire managers for setting desired medium and long term outcomes for specific ecological values that are potentially most impacted on by fire. Opportunities to extend knowledge and build on the outcomes of this project should be considered important.

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Contents

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Introduction 1Definition of biophysical units2Study Area2Report Structure4Stage 1 - Literature Review 5Previous studies in the ecological subdivision of landscape5The use of the terms biophysical regions, ecoregions, bioregions and watersheds in the literature 5Scale considerations6Biophysical boundaries and the use of watersheds as a landscape management tool for the Greater Grampians LMU 7Biophysical units for fire management7Background7Fire responses of flora7Ecological vegetation divisions (EVD) association with fire9Fire responses of fauna9Vital attributes and known fire regimes for Key Fire Response Species 11Key fire response species for the Greater Grampians LMU 12Fauna 12Flora 14Habitat and landscape features that influence biophysical boundaries 15Identifying biophysical boundaries in the Greater Grampians Landscape Management Unit 16Guidelines for Consideration 16Biophysical Boundaries within the Greater Grampians LMU 17Assumptions 18Integration of potential biophysical boundaries and fire 18Stage 2 Creation and Rationale of Biophysical Units within the GGLMU 19Development of Initial Biophysical Units 19Existing Data 20Consultation with Parks Victoria and DSE 21Data storage 22Biophysical Units 23Biophysical units and ecological vegetation division composition 23Strength of biophysical unit boundaries 34Further information 39Limitations 39Further investigation 39Acknowledgements 41References 42Appendix 1Biophysical Unit Profiles 46Appendix 2Threatened species status categories 129Appendix 3Rare or Threatened Flora Species within each biophysical unit 131Appendix 4Threatened Fauna Species within each biophysical unit 141Appendix 5Potential Fauna Key Fire Response Species Profiles 145Appendix 6Workshop participants 191

Figures

Figure 1-1Study Area: Location of the Greater Grampians Landscape Management Unit3

Figure 4-1Ordination of the ecological vegetation division composition for biophysical units in the

Greater Grampians landscape management unit (Stress 0.1)33

Figure 5-1Strength of boundaries of proposed Biophysical Units in the Greater Grampians LMU36

Figure 5-2. Occurrences of wildfire across Biophysical Units boundaries proposed for the Greater Grampians LMU37

Tables

Table 2-1Nominated fauna KFRS as candidates for ecological boundary assessment and monitoring for fire management planning in the Greater Grampians Landscape

Management Unit13

Table 2-2Key Fire Response Flora Species as candidates for biophysical unit monitoring in the

Greater Grampians Landscape Management Unit15

Table 3-1List of data layers used in the Spatial Analysis component of the project supplied by

Parks Victoria20

Table 3-2Changes to the biophysical units based on consultation with PV and DSE21

Table 5-1.Attributes of boundary strength based on physical properties for proposed Biophysical

Units in the Greater Grampians LMU35

Map of Greater Grampians LMU Biophysical Units

Located at end of the report

(Introduction)

1. Introduction

Parks Victoria commissioned this project to identify options for biophysical units within the Greater Grampians Landscape Management Unit (GGLMU).

Background

The project arose out of the requirement under the Code of Practice for Fire Management on Public Land (DSE 2006) to develop an integrated Fire Ecology Strategy (FES) to address the appropriate use or exclusion of fire at a landscape level. When developing a FES, the first step in the planning process is the identification of appropriate Landscape Management Units (LMUs), recommended to be between 10,000 ha and 200,000 ha in size (Parks Victoria 2003). Currently, at over 200,000 ha, the Greater Grampians LMU is too large to use as a single LMU for planning prescribed burns to meet ecological outcomes. Therein, the opportunity existed to subdivide the GGLMU into biophysical units (BPU) which reflected the complexity of the GGLMU area and which would identify specific ecological objectives based on the characteristics of each biophysical unit. The new biophysical units are expected to sit above previous fire management boundaries used within the Greater Grampians LMU. Previous fire management boundaries included:

Fuel Management Zones across the LMU;

EVC groups across the entire park, in particular Heathland;

Heath Mouse meta population boundaries; and

Interim Fire Management Units (based on human community location and catchments). Ecological factors which were to be considered in the development of biophysical units included;

Landform;

Catchments;

Soils;

Ecological Vegetation Classes or Divisions,

Key Fire Response Species,

Fauna habitat boundaries (meta-populations); and

Priority flora and fauna (as identified in the Grampians Biodiversity Action Plan).

The Greater Grampians area has spatially explicit data on geomorphology, flora and fauna distribution, vegetation and climate. This presented a sound opportunity to develop quantitatively defined biophysical units for issues of fire management based on both biotic and abiotic factors.

Project Aim

The primary aim of this project is to identify options for biophysical units based on a review of ecological factors and to provide the rationale and implications of these options for the Greater Grampians LMU.

To this end, the project will ask the following questions:

What are the broad ecological boundaries across the Greater Grampians landscape?

What are the main landscape features / species / habitat types / Ecological Vegetation Classes / Ecological Vegetation Divisions that influence and form these boundaries?

What are the known fire regimes of the key landscape features / species / habitat types / Ecological Vegetation Classes / Ecological Vegetation Divisions/ that influence and form these boundaries.

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Project Objectives

The objectives of this project as identified by Parks Victoria were to:

Review current ecological literature / data sources / data bases, develop a list of key fire response species (flora and fauna), habitat and landscape features that influence the ecological boundaries, and document details of their known fire regimes.

Undertake a spatial analysis to determine, document and map identified options for ecological boundaries and the factors that have influenced them to use for planning prescribed fires to meet ecological outcomes within the Greater Grampians LMU.

Document the identified options and describe the rationale and implications of the options.

Lead a small workshop with local Parks Victoria and Department of Sustainability and Environment staff to discuss the influences on ecological boundaries.

1.1 Definition of biophysical units

In consultation with Parks Victoria and after a review of the literature (see Section 2.1), the following definition of biophysical units was considered appropriate for this project.

"A Biophysical Unit is a planning unit bounded by landscape factors be they physical or physiological or driven by species habitat preferences that potentially limit species movement or dispersal through the landscape, effectively creating independent units (meta-population model)."

Biophysical units in the Greater Grampians LMU are used by land and fire managers as the base scale for setting desired medium and long term outcomes for specific ecological values that are potentially most impacted on by fire.

It should be noted that the above definition encompasses the following consideration:

Sound, scientific research will be used as the basis for developing desired medium and long term ecological outcomes within the biophysical units for the overall benefit of the Greater Grampians Landscape Management Unit.

The biophysical units delineated for the Greater Grampians LMU are an integrated set. The biophysical units are strongly connected with other biophysical units in the landscape. The recognition of such connectivity will continue to underpin land and fire management of the Greater Grampians LMU.

1.2 Study Area

The Greater Grampians Landscape Management Unit is situated in central west Victoria and includes the Grampians National Park, Black Range State Park, Grampians State Forest and contiguous public land. The LMU covers an area of approximately 220,000 ha and falls largely within the Greater Grampians and Dundas Tablelands bioregions. The LMU crosses both land tenure and agencies (Parks Victoria, Department of Sustainability and Environment). Figure 1-1 shows the extent of the Greater Grampians LMU.

(Introduction)

Introduction

Figure 1-1 Study Area: Location of the Greater Grampians Landscape Management Unit

1.3 Report Structure

The report has been divided into two sections, Stage 1 and Stage 2. The first section (Stage 1) contains the literature review which focused on two key issues, the creation of biophysical units and the fire response of key fire response species (flora and fauna), relevant to the GGLMU. A key output from the literature review was the development of the fauna KFRS profiles (see Appendix 5). This process was instrumental in identifying which fauna species were suitable for consideration as a key fire response species for the GGLMU, which species would be suitable for monitoring the success of the FES, and, just as importantly, where the knowledge gaps lay. The second section of the report, Stage 2, contains a description of the final biophysical units, the ecological factors which influenced the boundaries of these units, the rationale for the final decision and the implications of these units for the Greater Grampians LMU.

(Introduction)

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2. Stage 1 - Literature Review

2.1 Previous studies in the ecological subdivision of landscape

The key criteria are not to be found simply in the vegetation, in the soil profile, in the topography and geology, in the rainfall and temperature regimes, but rather in the spatial coincidences, patterning and relationships of these functional components

(Rowe 1980 in Khron 1999, pg. 1).

Land managers are often faced with the issue of how to appropriately subdivide large landscapes into smaller, homogenous units for research and/or management purposes (Krohn, 1999).

Climate, modified by landform, was recommended by Bailey (1996) as the logical criterion for delineating ecosystem boundaries. Bailey (1995) and Bailey et al. (1994) used these two variables to map the major ecoregions of the United States (Krohn 1999). However, Rowe (1980) had previously argued that maps which use abiotic variables cannot be considered ecological maps unless the abiotic boundaries matched boundaries of biological significance (Krohn 1999). To this end, McMahon (1990) delineated biophysical boundaries of Maine by overlaying climate with topographical maps. McMahon (1990) then assessed the relationship between these ecoregions with climate, soil variables and species richness using canonical correspondence analysis. However, Krohn (1999) commented that this relationship was not used to further delineate the ecoregion boundaries and that the suggestion by Rowe (1980) to check abiotic boundaries to biotic boundaries had not actually been undertaken. Krohn (1999) added to McMahons work by incorporating both abiotic and biotic variables to developed biophysical regions of Maine. In his analyses Krohn (1999) used the following features:

Abiotic: Elevation, Slope, Heat Accumulation, Snowfall, Total Precipitation.

Biotic: Vertebrate species ranges, woody plant species ranges

Gallant et al. (1998) commented on the difficulty of applying quantitative weightings to represent the importance of different environmental factors for delineating ecoregions. Having a set weighting alone does not work given that the importance of environmental factors, and the accuracy with which they are mapped, can vary within and among ecoregions (Gallant et al. 1998). The importance of knowledgeable interpretation of preliminary zones by land managers is essential for this reason.

2.2 The use of the terms biophysical regions, ecoregions, bioregions and watersheds in the literature

The terms biophysical region and ecoregion are often used interchangeably in the literature. This point was identified by McMahon (1990) who used the term biophysical regions while recognising the synonymy of this term with ecoregions. Ricketts et al. (1999), when mapping ecoregions across North America, defined ecoregions as:

a relatively large area of land or water that contains a geographically distinct assemblage of natural communities. These communities (1) share a large majority of their species, dynamics, and environmental conditions and (2) function together effectively as a conservation unit at global and continental scales

(Ricketts et al. 1999 pg. 7).

Similarly, Gole (2006), on describing the south-west Australia ecoregion, defined ecoregion as: a large area of land containing a geographically distinct assemblage of species, natural

communities, dynamics and environmental conditions(Gole 2006, pg. 4).

At a more local level, Cole (2000) discussed the role of biophysical mapping in the national recovery plan of the critically endangered Central Rock-rat Zyzomys pedunculatus (occurring in disjunct populations in northern Australia). Cole (2000) defined biophysical mapping as:

the mapping of the biological and physical attributes of the landscape. The landscape is mapped into Vegetation Units, each of which represents an area that is relatively

homogeneous with respect to the vegetation, landform, geology, plant community and soil

(Cole 2000).

Omernik and Bailey (1997) propose that ecoregions be thought of as multipurpose regions, designed to show areas within which the aggregate of all terrestrial and aquatic components is different from or less variant than that in other areas. They are intended to provide a spatial framework for ecosystem assessment, research, inventory, monitoring and management.

The Interim Bioregionalisation for Australia (IBRA) delineates 80 bioregions across Australia, of which 11 occur in Victoria (DNRE 1997). The IBRA bioregions represent a landscape based approach to classifying the land surface of Australia, and each bioregion reflects a unifying set of major environmental influences which shape the occurrence of flora and fauna and their interaction with the physical environment across Australia. In recognising that the broad scale of the national bioregions may not discriminate adequately between areas with meaningful differences at the state level, the national bioregions have been refined. As a result of this process, 21 Victorian bioregions have been idenfied and described in a state context. The Victorian bioregions are used as broadscale mapping units for biodiversity planning. The bioregions capture the patterns of ecological characteristics in the landscape, and at a state level provide the natural framework for recognising and responding to biodiversity values (DNRE 1997).

2.2.1Scale considerations

Many of the previous attempts at creating biophysical regions and/or ecoregions (i.e. biroegions) have focused on classifying the landscape across entire states or countries. For example, Demarchi (1996), when mapping the ecoregions of British Columbia, recommended that ecoregions be mapped at 1:500,000 for regional strategic planning purposes. Other authors, however, believe that there should be no designated minimum area for ecoregions on the basis that exceptions to a size rule can always be found (Gallant et al. 1999, Ricketts, et al. 1999). Bailey (2004a) sits ecoregions at the macro scale from which subregions can then be identified to a meso (landscape) and micro (site) level.

There is a saying in landscape planning think globally, plan regionally and act locally (Richard Foreman in Steiner 2000, pg. 52). Subsequently, it is important to establish a hierarchy of levels to ensure that the planning area is understood as part of the larger system (Steiner 2000; Bailey 2004a). For example, in Australia there are 80 recognised bioregions, 11 of which occur in Victoria

(e.g. Victorian Midlands). In Victoria, the 11 represented Australian bioregions have been sub- divided into 21 Victorian bioregions (DNRE 1997). One of these bioregions is the Greater Grampians bioregion.

To identify an appropriate base scale for land and fire managers to set desired medium and long term outcomes for a range of ecological values in the Greater Grampians LMU (i.e. Greater Grampians bioregion, and part of Dundas Tablelands bioregion) it is necessary to extend the hierarchy in place under the Victorian bioregion framework.

At a landscape scale, such as the Greater Grampians LMU, Steiner (2000) recommended that large river basins be used at the regional level and considered watersheds to be an ideal unit for ecological planning at the local level. Similarly, Eugene Odum (ecologist) noted the value of using watersheds in planning based on the premise that the whole drainage basin, not just a body of water, must be considered as the minimum ecosystem unit (Steiner 2000). Watersheds are defined as the area of land that drains water, sediment and dissolved materials to a common outlet at some point along a stream channel (Dunne & Leopold 1978, pg. 475 in Steiner 2000, pg. 52). However, Omernik and Bailey (1997) caution against the misuse of watersheds as study units where watershed delineation is particularly problematic. They identified karstlands, glaciated areas, excessively arid areas (50% area covered by sand) as particular areas which hinder or exclude the use of watershed delineation for units (Omernik & Bailey 1997). Subsequently, watersheds cannot be considered a consistent tool in delineating units. Bailey (2004b) cautioned that a non-uniform method of subsection delineation can result in maps of subsections varying widely. This situation may lead to the results of the mapping becoming difficult to communicate convincingly to land managers and decision makers (Bailey 2004b). Additionally, Omernik and Bailey (1997) argue that boundaries of ecological significance emerge from studies which reveal changes in ecosystem components. Subsequently, synthesising ecosystem units by adding different components together which are defined as features in themselves (e.g. watersheds, soils, timber), is antithesis to this process. Omernik and

(Stage 1 - Literature Review)

(Stage 1 - Literature Review)

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Bailey (1997) recommend using watersheds and ecoregions together to manage environmental resources, keeping in mind that watersheds may cover more than one ecoregion, and should not necessarily be used to delineate the ecoregion.

2.3 Biophysical boundaries and the use of watersheds as a landscape management tool for the Greater Grampians LMU

Using the hierarchical scale identified by Bailey (2004a), the subdivision of the Greater Grampians Landscape Management Unit must necessarily take place at the meso (landscape) level. Therefore, for the purposes of this report, biophysical units sit under ecoregions as described by Bailey (Bailey 1996, 2004a, 2004b). The use of watersheds as a factor in delineating biophysical units at this level was justified, particularly in the Greater Grampians LMU which does not contain any landform characteristics that pose a hindrance to the use of watersheds (see section 2.2). Additionally, research has found that elevation and watersheds are able to better explain differences in patterns of various species assemblages than were coarser ecoregions (e.g. Spindler (1996) found watershed and elevation explained patterns in macroinvertebrate community structure in Arizona streams).

The development of ecoregions within Victoria, and indeed Australia, is outside the scope of this report, yet there exists the opportunity to see how well the biophysical boundaries created in this report fit within broader ecoregion mapping of Victoria.

2.4 Biophysical units for fire management

As previously discussed, the initial concept for developing biophysical units within the Greater Grampians LMU was to address the appropriate use or exclusion of fire at a landscape level (see Section 1). This aligns with an international shift of land management practices from focusing on individual resources to a more holistic approach of managing whole ecosystems (Bailey 2005). An analysis of ecosystem patterns is necessary given that at finer scales, considerable variation in fire regimes occur due to local topography, vegetation and microclimate (Bailey 2005). Understanding the impact of fire on key flora and fauna species within the Greater Grampians LMU is imperative to ensure that fire prescriptions for each biophysical unit maintains the viability of populations within and between units. The following review considers the potential effects of fire on flora and fauna at a landscape scale and how this integrates with known ecological characteristics of flora and fauna to determine their potential to disperse, re-colonise and ultimately persist in the landscape fire mosaic.

2.4.1 Background

While there has been numerous comprehensive reviews of the effects of fire on flora and fauna (for examples see Williams et al. 1994; Tolhurst, 1996; Woinarski and Recher 1997; Woinarski 1999), these reviews have often been restricted by a limited understanding of the effect of fire on Australian biota, particularly for fauna. Much empirical research has considered effects based on components of the fire regime (i.e. timing, intensity) or effects associated with a single wildfire (e.g. Hewish 1984; Loyn 1997) or prescribed burn (e.g. Catling and Newsome 1981). There is a lack of understanding of the effect of contemporary fire management practices on biota, particularly the impact of repeated burning and the process of fire in shaping landscape structure and dynamics, and the associated response of biota. It is consistently reported that the influence of fire on flora and fauna is complex and continues to be poorly understood (e.g. Tolhurst 1996; Woinarski 1999; Clarke 2008); despite this fire as an ecological management tool is widely and regularly used in southeastern Australia.

2.4.2 Fire responses of flora

Fire is a known agent of change for plant ecosystems (Morrison & Renwick 2000). Fire frequency, season of occurrence and fire intensity are the three interrelated components of a fire regime which are known to affect plant population dynamics (Whelan 1995; Morrison & Renwick 2000). Bond and van Wilgen (1996) attribute short and long term population changes to fire frequency, while intermediate changes are believed to be influenced by season and intensity. Subsequently, the appropriate management of plant communities is dependent upon understanding the response of plant species to fire (Morrison & Renwick 2000). Knowing the vital attributes of plant species is an important tool in developing appropriate fire regimes that allow for plant persistence (Lord 1996),

given that different components of a fire regime effect different components of plants, as listed by Lord (1996):

Season plant phenology

Fire frequency life stages / span of plant

Fire intensity heat tolerance of plant tissue

Areal extent invasion afterwards for obligate reseeders

Climatic conditions following fire drought and plant stress, exhaustion of seed reserves etc. Within Victoria, prescribed burning was gradually developed after the 1939 wildfires, during which

uncontrolled fires burnt some 2,000,000 ha of land (Curtis 1998). The aim of prescribed burning is to reduce risk by removing fine fuels (up to 6 mm diameter) which consist of leaf litter and materials within a specified flame height (Curtis 1998). While this has the ability to alter habitats, research on the impact of different fire regimes was still insufficient some 60 years after this practice was established (Curtis 1998). However, with the growing realisation of the impact fire regimes can have on plant populations, intensive effort has now been undertaken to collect the basic data on the response of plants to fire (Clarke & Knox 2002). This research has assisted in building a collective understanding of the fire responses of flora (Bradstock et al. 1997; Curtis 1998; Morrison

& Renwick 2000). For example, Noble and Slatyer (1981) related variation amongst species in their response to a given fire regime to their life history characteristics. Bradstock et al. (1997) found that while fire regimes affect floristic composition, they have no significant impact on species richness. Curtis (1998) found that inappropriate fire regimes can lead to the local extinction of some species (e.g. Xanthorrhoea australis Austral Grass-tree). Additionally, Bell and Pate (1996) reviewed the available literature and found that there was a surprising level of uniformity in fire- related behaviour of widely separated plant groups, including the Proteaceae, the Fabaceae and the Restionaceae.

Overall, data collected on the response of plant species to fire has tended to focus on key questions such as (Clarke & Knox 2002):

Is the species killed by fire?

Does the species resprout after fire? and

Where are seeds stored?

This approach was initially criticised since factors including genetic factors, climate and fire intensity can produce variable fire responses (Morrison & Renwick 2000; Clarke & Knox 2002). Additionally, habitat itself can influence different functional responses. In a study of shrubs in the New England Tablelands, NSW, Clarke and Knox (2002) showed that shrub species on rocky outcrops were generally killed by fire (that is they were obligate seeders), while more than 70% of shrub species in the grassy forests, heaths and shrubby forests resprouted after fire. A similar case was found in the two forms of Banksia marginata (Silver Banksia) occurring in the Grampians National Park. The taller tree-form which occurs in the forested environments can be killed by fire and does not resprout, while the shrub-form, found in heathy habitats, is able to resprout post-fire (Cheal under review).

Plant assembalages are also affected by time since fire. The importance of time since fire on plant assemblages was highlighted by a recent study of plant communities in the Florida uplands. Boughton et al. (2006) found that time since fire influences the distribution of plant assemblages with Rosemary Scrub occurring more frequently in longer unburnt areas. This finding is consistent with the vital attribute information for the dominant species of that community, Ceratiola ericoides. This species is an obligate seeder that is killed by fire and requires 10-15 years to reach reproductive maturity (Boughton et al. 2006). Alternatively, the dominant species of the more mesic communities Scrubby Flatwoods and Flatwoods, are primarily re-sprouters, and therefore, the assemblages of these communities were not greatly changed by fire (Boughton et al. 2006).

2.4.3 Ecological vegetation divisions (EVD) association with fire

Bailey (2005) suggested categorising vegetation units as one of three fire regimes types:

fire-dependent/influenced (fundamental to sustaining native plants and animals, resilience and recovery following exposure to fire)

fire-sensitive (frequent, large and intense fires are rare events, plants lack adaptations to rapidly rebound from fire, areas typically cool or wet and consist of vegetation that inhibits the start or spread of fire)

fire-independent (fires largely absent due to a lack of vegetation or ignition source).

However, these categories are quite broad and to categorise each of the 208 ecological vegetation classes within the GGLMU as one of the above categories would not be useful exercise for landscape scale fire management. Alteratively, the use of ecological vegetation divisions (EVD) provides an opportunity to manage vegetation at such a scale. EVDs consist of two or more ecological vegetation classes (EVC) and are subsequently large-scale vegetation units. While these units are not suited to fine-scale purposes, they are suited to large-scale management, particularly in relation to fire (Cheal under review). Cheal (under review) identified 32 EVDs throughout Victoria, 18 of which occur within the Greater Grampians LMU. However, while supporting the use of EVDs for fire management, Cheal (under review) does stress that research on vegetation and fire regimes is completely lacking for most vegetation communities and that future use of the EVDs under various fire regimes are therefore speculative.

For each EVD, Cheal (under review) identified and described the following components:

Maximum Fire Interval;

Minimal Interval for High Intensity Fires;

Mimimal Interval for Low Intensity Patchy Fires;

Growth Stages:

Renewal (Immediately post-fire);

Juvenility (First few seasons post-fire);

Adolescence (Soon after fire);

Maturity (Extended period inter-fire); and

Waning (Toward upper-limit of desirable fire age).

The three fire intervals given above are listed for each EVD that occurs within a given biophysical unit (see Appendix 1 Biophsyical Unit Profiles). Refer to Cheal (under review) for a detailed description of the growth stage characteristcs for each EVD.

2.4.4 Fire responses of fauna

The response of fauna to fire has been reviewed (e.g. Wilson 1996; Tolhurst 1996; Woinarski and Recher 1997; Woinarski 1999). The broad findings of relevant research on the response of fauna to fire are detailed below.

Fire may have direct or indirect impacts on fauna. Direct impacts largely relate to the mortality of species and include the ability of fauna to avoid and survive fire, and for mobile animals to recolonise recently burnt habitats, patches of unburnt habitat within the fire area, or nearby unburnt habitat. The intensity of fire has an important bearing on the level of direct impacts on fauna. For example, high intensity wildfire may lead to high numbers of fauna mortalities (e.g. Wegener 1984), particularly for less mobile species.

The indirect effects of fire on fauna and their habitats are varied depending on the resource requirements of species and the availability, recovery, and spatial and temporal distribution of these resources in the post-fire environment, as well as other processes such as predation. Resource dynamics, in turn, are dependent on the severity, extent and frequency of fire. For some fauna, strong patterns between vegetation seral stages (i.e. growth stages) and occurrence (i.e. presence) or peak population parameters have been found. Some species are strongly associated with early post-fire habitats (e.g. Eastern Grey Kangaroo (MacHunter et al. under review)), while

others are strongly associated with mid or late seral stages (e.g. Long-nosed Potoroo (Claridge and Barry 2000)) along the trajectory of vegetation succession following fire.

The frequency of fire impacts indirectly on fauna by way of modifying vegetation structure causing long-term change in availability of particular habitats. Too frequent fire for example, has been shown to result in loss of plant species and simplification in vegetation structure. Species associated with mature and senescent stages in vegetation development may be particularly vulnerable to repeated, frequent fire.

Fauna display a range of responses to fire. Loyn et al. (2004) discussed a set of four possible fauna response curves to logging in southeastern Australian forest. The underlying mechanism for these fauna responses is the process of disturbance in forested landscapes. It is therefore possible that these curves may be generalised to apply to fire as the disturbance mechanism (see MacHunter et al. under review). Comparable responses by fauna are evident in the fire ecology literature; therefore, the curves described by Loyn et al. (2004) provide a usable framework for describing faunal response following fire. Detailed descriptions of these curves are available (Report available as pdf. file at www.fwpa.com.au/Resources/RD/WAPIS/PN99.808%20%20Part

%20C), but they can be summarised as:

a. Some fauna show an early positive response following fire and increase numbers in the few years following burning before stabilisation of population numbers at near pre-fire levels as time since fire increases.

b. Some fauna show an early positive response following fire and increase numbers in the few years following burning, but then population numbers decline through time to substantially below pre-fire levels.

c. Some fauna decline immediately following fire and then gradually recover population numbers as time since fire increases.

d. Some fauna may decline following fire and are lost or never recover population numbers to pre-fire levels.

For example, these response curves fit well with descriptions by Fox (1983; in FEWG 1999) whom for a heathland small mammal assemblage classified species as occupying an early regeneration niche (e.g. P. novaehollandidae and I. obesulus) or a late regeneration niche (e.g. R. lutreolus, R. fuscipes and A. agilis). Species entered the post-fire succession environment when their habitat requirements were met and were replaced or declined when conditions became sub-optimal. Some species (e.g. P. novaehollandidae) re-enter late successional vegetation as late- successional species begin to decline (e.g. R. fuscipes) in response to senescing of understorey in effect opening it up and having the physiognomy of the earlier post-fire environment (Fox 1996; in FEWG 1999).

The long-term survival of fauna over repeated fires is dependent upon two key features: i) the ability of species to maintain life-cycle processes; and ii) the maintenance of vegetation structure over time as habitat for animal species. The spatial characteristics of fire are critical to faunal responses (see Stevens 2008). Recovery after fire is driven by both the ability of species to re- colonise burnt habitat and their ability to survive in the post-fire environment. This in turn is affected by the scale and intensity of the burn, particularly as it relates to the patchiness of unburnt habitat in the burn area. The patchiness of a fire has a large bearing on the response of fauna; unburnt patches, even those that are very small, provide refugia and habitat to sustain populations during and in the immediate-to-early post-fire environment (Stevens 2008). Based on existing knowledge, application of fire that achieves a patchiness of burnt and unburnt habitats within a single event may satisfy a precautionary approach (Bradstock et al. 1995). The scale of burn becomes less important where a suitable level of patchiness is achieved as species have refugia in unburnt patches that facilitate survival, provide a source of colonisers and enable use of recovering post-fire environments. A patchy burn is also likely to increase heterogeneity within the burn area. Such application needs to be adaptive to new information.

Fire also threatens key habitat attributes for fauna. For example, high-intensity fire reduced the availability of trees with hollows by 38%, although in the long-term it increased the rate of hollow formation by direct excavation or by providing sites for fungal or termite attack (Inions et al. 1989). There is a lack of information on the effect of lower intensity ecological and managed burns on the availability of such resources. For example, while high intensity fire may initiate hollow

(10)

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development, prescribed burns (i.e. low intensity fire) may not be of a high enough intensity to initiate hollow development (Taylor and Savva 1988).

There is a considerable number of species that are associated with relatively long-unburnt environments (Woinarski and Recher 1997), or habitat components associated with such stages such as extensive coarse woody debris (e.g. Brown Treecreeper), and therefore are strongly disadvantaged under fire regimes of widespread high frequency burning (Flora and Fauna Action Statement Nomination 664 Inappropriate fire regimes; Woinarski et al. 2004). The importance of maintaining relatively long unburnt habitat in the landscape must be planned for once burnt such habitats are not readily reinstated or supplemented and there may be a substantial time-lag associated depending on the availability of senescent or mature vegetation approaching senescence in the landscape. As for all post-fire seral-stages in vegetation communities, such areas need to be available at an appropriate scale in the landscape to be viable options for use by associated fauna.

There is very little information on the effect of fire on reptiles and frogs, particularly in southeastern Australia (Wilson 1996). These fauna groups are most likely to be impacted by changes to the litter and ground layers as a result of fire. Due to their relatively low mobility and terrestrial nature, some reptiles and amphibians may suffer high mortality rates as a direct effect of fire, particularly during high intensity wildfire.

A complex interaction of many factors influence the impacts of a particular fire, or series of fires, on fauna including characteristics of a particular fire, the presiding fire regime, pre- and post-fire environmental conditions and the biology and ecological requirements of species. The life-cycles of fauna (and flora) are central to the study of fire effects (Whelan et al. 2002). How a species or population changes following fire is determined by the fates of particular organisms (mortality, reproductive rate, species movements) and the life-stage of these organisms (i.e. age class, maturity). An understanding of the life history characteristics (viz. vital attributes) is fundamental when making predictions about species response to fire (see Whelan et al. 2002).

2.4.5 Vital attributes and known fire regimes for Key Fire Response Species

Key Fire Response Species (KFRS) are those whose vital attributes (key life history attributes that determine how a species lives and reproduces) indicate that they are vulnerable to either regimes of frequent fires or to long periods of fire exclusion (DSE 2004; MacHunter et al. under review). KFRS are used to define the lower and upper tolerable fire interval to guide ecological burning. For flora, the lower tolerable limit is set by the species that takes the longest time to reach breeding maturity (FEWG 2004). The upper tolerable limit is set by the species with the shortest time to local extinction as a result of senescence (FEWG 2004). Knowledge of the vital attributes for Victorian flora species has been compiled (D. Cheal, ARI) and flora KFRS have been used to develop and apply ecological burns. Until recently, the integration of fauna into this process however has been ad hoc as there has been limited understanding of the effects of fire on fauna in Victoria (Clarke 2008). The vital attributes of most fauna are poorly understood and as a result selection of KFRS has been difficult (Clarke 2008; MacHunter et al. under review). Concurrent with the CEM project, a process for integrating fauna in fire management planning was undertaken (MacHunter et al. under review) which included the design of a model to facilitate the use of fauna KFRS and habitat parameters. The Greater Grampians LMU project provides an example of how a regional initiative aligns with the statewide approach to fire management planning.

To define potential KFRS, the vital attributes of the species must be known. For flora, the vital attributes, including method of persistence, conditions required for establishment and relative longevity, of many genera and species are relatively well understood. This is not the case for fauna. FEWG (2004) considered shelter, food and breeding requirements to largely determine a fauna species response to fire and its post-fire successional requirements. However, other autecological attributes are also likely to be important including movement/dispersal capabilities and timing of breeding. For fauna, habitat parameters may also function as vital attributes. For example, the use of tree hollows or coarse woody debris or requirements for complex vertical structure or dense ground-layer vegetation are intimately linked to the autecological attributes of species, and therefore are likely to represent key vital attributes. A range of autecological attributes representing potential vital attributes for fauna need to be considered.

Breeding attributes breeding period, nest guild, brood size, broods per season

Movement/dispersal attributes dispersal distance, small scale movements, home range size, potential barriers to movements

Food attributes food item, foraging behaviour, generalist/specialist

Habitat attributes broad habitat type, fine habitat type, hollow-dependent, coarse woody debris dependent, associated flora, EVD alliance, EVD seral stage

2.5 Key fire response species for the Greater Grampians LMU

2.5.1 Fauna

The investigation and selection of potential KFRS for the Greater Grampians LMU was limited to vertebrate species recorded from the Greater Grampians LMU (Atlas of Victorian Wildlife records; DSE 2004a).

A spreadsheet was established that listed potential species and contained a field for each of the vital attributes, as well as fields for specific information about fire threats, relevant species-specific information (e.g. timing of torpor), sources of information and comments. An extensive review of available literature was then undertaken to compile known information and populate the spreadsheet fields. Beyond the published literature, inferences were made based on expert judgment.

The output of this stage of the review is represented in Appendix 5 Potential Key Fire Response Species Profiles.

Three criteria were applied in the selection of potential Key Fire Response Species for the Greater Grampians LMU (Table 2-1).

1. The response of the species was well-known, or inferences about its fire response were considered sound.

2. The species displays a strong seral-stage response following fire, or inferences about its seral-stage fire response were considered sound.

3. The species was easily identifiable (i.e. if present, should be easily detected) and could be readily monitored.

These criteria were closely matched with those used to identify KFRS for fauna in Victoria (MacHunter et al. under review), resulting in a strong compatability between the set of potential KFRS proposed for the Greater Grampians LMU and those identified in the statewide project (MacHunter et al. under review). The species KFRS information provided in MacHunter et al. (under review) has been incorporated into the KFRS profiles (Appendix 5) and any important differences have been highlighted.

As part of the selection process of KFRS in the Greater Grampians LMU, the number of records of the species in the AVW (DSE 2004) was used to indicate the utility of the species for monitoring a high number of records indicated that the species was readily detectable and therefore could be monitored through time. The utility index was considered in combination with information on vital attributes to qualitatively assign a KFRS suitability index to species. This index rated the potential (1 = high through to 5 = low) for species to be utilised as KFRS in the Greater Grampians LMU.

The use of a single species representative of a group of species with similar ecological requirements (e.g. mid-storey invertebrate feeders (e.g. Golden Whistler, Brown Thornbill, Grey Fantail) to represent KFRS was also considered. This approach was also used by MacHunter et al. (under review) when identifying candidate KFRS for Victorian EVDs.

One potential dilemma that must be considered when selecting KFRS is the need to manage fire to meet requirements of threatened and significant species, that may have specific requirements and may not be suitable candidates as KFRS (by their very nature, such species are likely to occur in low numbers and therefore have reduced utility as KFRS). Decisions on such species still need to be incorporated in fire management planning.

Table 2-1Nominated fauna KFRS as candidates for ecological boundary assessment and monitoring for fire management planning in the Greater Grampians Landscape Management Unit

KFRSKFRSPotential ecological ratingboundaries

Major EVD allianceEVD seral stage

Agile Antechinus

2Major riverGrassy/Heathy Dry ForestMaturity onwards

Dusky Antechinus

1Vegetation typeRiparian Forest, Swampy Scrub.

Heathland (sands)

Maturity onwards

Yellow-footed Antechinus

2Ridgeline/escarpment Major river

Inland GDR (?)

Grassy/Heathy Dry Forest, Alluvial Plains Woodland, Forby Forest

Maturity onwards

Feathertail Glider

3Ridgeline/escarpmentGrassy/Heathy Dry Forest, Tall

Mixed Forest, Foothills Forest

Maturity onwards

Sugar Glider4NAGrassy/Heathy Dry Forest, Foothills Forest

Squirrel Glider4Inland GDR (?)Grassy/Heathy Dry Forest, Alluvial

Plains Woodland

Maturity onwards Maturity onwards

Eastern Pigmy Possum

Common Ringtail Possum

3Vegetation type (?)Heathland (sands) (?)

Grassy/Heathy Dry Forest (?)

2NAGrassy/Heathy Dry Forest, Forby Forest

Adolescence- Maturity onwards

Adolescence- Maturity

Long-nosed Potoroo

Southern Brown Bandicoot

2 NAGrassy/Heathy Dry Forest (?)Maturity onwards

3 Vegetation typeHeathland (sands)Adolescence- Maturity

Swamp Rat1Ridgeline/escarpmentHeathland (sands)Adolescence

Maturity

Heath Mouse1Ridgeline/escarpment

Vegetation type

Smoky Mouse1Major river

Vegetation type

Heathland (sands) Grassy/Heathy Dry Forest

High Altitude shrubland Rocky Knoll

Maturity (?)

Maturity onwards (?)

Brown Treecreeper

White-throated Treecreeper

Golden Whistler

Eastern Yellow Robin

2NAGrassy/Heathy Dry Forest Alluvial Plains Woodland Forby Forest

1 NAGrassy/Heathy dry Forest, Forby Forest, Foothills Forest, Tall Mixed Forest

2 NA Grassy/Heathy Dry Forest, Forby Forest, Rocky Outcrop Shrubland (?), Foothills Forest (?)

3 NATall Mixed Forest, Tall Mist Forest, Riparian Forest, Grassy/Heathy Dry Forest, Forby Forest, Foothills Forest

Juvenility Maturity onwards

Adolescence- Maturity onwards

Adolescence- Maturity

Adolescence- Maturity

KFRSKFRSPotential ecological ratingboundaries

Major EVD allianceEVD seral stage

Grey Fantail4NAGrassy/Heathy Dry Forest Forby Forest

Rocky Outcrop Shrubland

Juvenility-Maturity

Buff-rumped Thornbill

2NAGrassy/Heathy Dry Forest Forby Forest

Renewal Maturity onwards

Mistletoebird4NAGrassy/Heathy Dry Forest, Forby forest, Tall Mixed Forest

Maturity onwards

White-browed Babbler

4 NAUndeterminedMaturity onwards

Brown Toadlet5Soil typeLowland Forest (?) Damp Forest (?) Foothills Forest (?)

Adolescence onwards (?)

(?) - are potential factors that are likely based on limited information in the literature or databases.

2.5.2 Flora

The Key Fire Response level and vital attribute information was attached by Parks Victoria to Flora Information Systems (FIS) records for the Greater Grampians LMU. Flora species suitable for use as a Key Fire Response Species within the GGLMU were determined using the Key Fire Response Level developed by Cheal (under review). Cheal categorised the level of suitability by the degree to which they met the following criteria:

a) well known fire responses;

b) precisely timed fire responses;

c) visibly present within the community at a range of fire ages; and

d) recognisability and distinctiveness from other species in the field.

Based on this criteria, Cheal (under review) identified three categories; Highly Suitable, Suitable and Somewhat Suitable. Highly suitable categories have well known fire responses, are responsive to fire regimes, are visibly present in the community in (nearly) all ages since fire and are readily recognisable in the field. This allowed a search of all KFRS within the GGLMU which identified the following:

there were 16 Highly Suitable Species (Level 1) within the GGLMU (two of which are considered rare or threatened);

there were 93 Suitable Species (Level 2) within the GGLMU; and

there were 148 Somewhat Suitable (Level 3) Species.

Of the 16 Highly Suitable Species (Level 1), nine species have been identified which occur throughout the GGLMU, making them potentially suitable for monitoring purposes (see Table 2-2).

Table 2-2Key Fire Response Flora Species as candidates for biophysical unit monitoring in the Greater Grampians Landscape Management Unit

Potential

Species Name

KFRS

Record Count

No. of biophysical units

Comments

High

Acacia mearnsii

1

162

13/15

Distributed throughout the Grampians N.P

High

Allocasuarina muelleriana subsp. muelleriana

1

90

11/15

Distributed throughout the GGLMU

Very High

Banksia marginata

1

504

14/15

Distributed throughout the Greater Grampians region but the woodland form is killed by fire while the heathland form resprouts

Very High

Banksia saxicola

1

88

8/15

Important Species VROT. Two populations occur on the boundary of the LMUs on both Victoria Range and the Mt William Range. Studies have shown these two populations show genetic differentiation

Very High

Brachyloma daphnoides

1

280

14/15

Distributed throughout the Greater Grampians region - representative species

High

Callitris rhomboidea

1

321

13/15

Distributed throughout GNP but does not occur in the southwest Greater Grampians region

High

Cassytha pubescens s.s.

1

283

14/15

Distributed throughout the Grampians N.P but only a few outlying records in the Black Range, Rocklands Reservoir regions

Very High

Conospermum mitchellii

1

118

11/15

Scattered throughout GGLMU from Victoria Range to the Mt. William Range. Many records are on the boundary between two LMUs

Very High

Xanthorrhoea australis

1

437

13/15

Commonly distributed in central and northern region of the Grampians National Park, few records outside park.

2.6 Habitat and landscape features that influence biophysical boundaries

A biophysical boundary (see Strayer et al. 2003 for a review) is considered here as a landscape- scale factor, be it physical (e.g. ridgeline, waterway, road) or physiological (e.g. condition exceeding desiccation limit, acidic soil), or driven by species habitat preferences (termed habitat boundaries herein), that potentially limits species movement/dispersal through the landscape, effectively creating independent units (i.e. meta-population model) in the landscape.

There is limited available information on potential biophysical boundaries and their function across landscapes, particularly in Australia. Boundaries can be either sharp or smooth and their function,

as well as our ability to detect them, is dependent on the variable (e.g. species, community) used (Fortin 1996).

Physical barriers to movement provide the most obvious examples of biophysical boundaries. Elements of landscapes that may physically restrict (i.e. impermeable) the movement of organisms include mountain ranges, and associated rocky escarpments, and water bodies (e.g. Storm et al. 1976). At a finer scale, roads, fences and cleared easements may further restrict movement, particularly for small animals (e.g. McDonald & St. Clair 2004; Rico et al. 2007). While these features may provide a barrier in their own right, their integration with biotic components (i.e. vegetation) may contribute to the boundary effect. For example, while a mountain range may provide a barrier to dispersal of biota from lowland heath communities, the forested slope vegetation augments the boundary function by providing unsuitable intermediate habitat. Another example is the distribution of freshwater macroinvertebrates in the Grampians which depend on regular water flow to limit the effects of reproductive isolation (Robson et al. undated). Dry stream beds isolate populations of macroinvertebrates to isolated pools in the stream channel. The functioning of these types of biophysical barriers is dependent on their scale (i.e. stream width) and the types of organisms (i.e. body size, mobility) involved.

Species preferences for particular soil types or vegetation types may effectively create a boundary at its limits. The composition of the plant community determines the physical structure (i.e. architecture) and resource availability for fauna; it follows that vegetation communities in good condition should support a healthy biota. In turn, the process of fire is important in shaping the composition, structure and density of vegetation communities, and for most vegetation communities in south-east Australia, fire is essential (Williams et al. 1994). Vegetation communities, and indeed species within communities, have different fire requirements. That is, components of the vegetation have specific requirements relating to the frequency, timing, intensity and extent of fire. Within given vegetation communities (e.g. EVC, EVD) different fire events create a mosaic of different floristic compositions, structure and age-classes of vegetation. Fauna respond to such landscape pattern at several levels. First, some species are ubiquitously distributed in the landscape and display no strong association with any particular EVD (e.g. Grey Shrike-thrush). Second, some species display strong association with particular EVDs in the landscape (e.g. Heath Mouse). Third, some species display strong associations with specific growth stages of particular EVDs in the landscape (e.g. Southern Brown Bandicoot). Other species have highly-specific requirements. The levels at which species are related with these landscape components can be used to determine the limits of potential habitat boundaries. These boundaries have a physical component (i.e. EVD limit), but also a temporal component (i.e. growth stage of EVD).

Physiological boundaries may also occur at the landscape scale. For example, in southwest Western Australia subtle geographic barriers have prevented interbreeding within the Geocrinia rosea complex of frogs, resulting in differentiation of species even over very small distances of a few kilometres. It was found that small areas of unsuitable habitat (substrate/soil/climate) may be sufficient to isolate species with specific requirements for egg laying and survival (Wardell-Johnson and Roberts 1993). Similarly, the local distribution of Brown Toadlet, a species which occurs in the Grampians, is strongly influenced by soil pH (shows an association with acidic soil environments) (Chambers et al. 2006). From this it may be inferred that unsuitable soil types may function as a biophysical barrier for this species.

2.7 Identifying biophysical boundaries in the Greater Grampians Landscape Management Unit

2.7.1 Guidelines for Consideration

It is well known that the hydrological cycle drives geomorphic processes and is the basic abiotic process that functions in, and alters, ecosytems (Theberge 1989). Therefore, when identifying biophysical boundaries, watersheds are recognised as the key hydrological-geological unit which has both spatial and functional importance (Theberge 1989). The importance of using watersheds as ecological boundaries is highlighted by a recent case in Canada (Manseau et al. 2001). In response to concern over the severing of watersheds, the boundaries of a proposed new park (Manitoba Lowlands National Park, Canada) were reviewed to ensure that entire watersheds were captured to ensure sound ecological boundaries were used (Manseau et al. 2001).

Watersheds were used as the main driver of sub LMUs within the GGLMU. However, abiotic factors alone cannot be the sole determinant of sound biophysical boundaries (Theberge 1989). The following biotic guidelines, developed by Theberge (1989) were taken into consideration when identifying final biophysical boundaries for the GGLMU.

No rare or unique community should be severed - the Grampians National Park has four ecological vegetation classes (EVCs) that are endemic to the Greater Grampians area; Montane Rocky Shrubland, Montane Wet Heathland, Heathy Herb-Rich Forest and Sand Thicket Woodland (Parks Victoria 2003).

Boundaries should not sever highly diverse communities, especially wetlands, ecotones and riparian zones, or lakes. Research in the Florida uplands between ecotones and fire found that the boundaries of vegetation assemblages of variable flammability act as biophysical boundaries to the spread of fire (Boughton et al. 2006).

Boundaries should not sever communities with a high proportion of dependent faunal species. These communities contain habitat specialist which in general are more susceptible to environmental alterations than habitat generalists. For example, within the GGLMU, the threatened Heath Mouse is dependent upon heathland for its survival (Lindorff 1999).

Boundaries should not jeopardise the ecological requirements of either numerically rare or uncommon species. These species may be more vulnerable to local extinction and so must be considered. Within the GGLMU there are nine priority flora species and 12 priority fauna species that should be considered in relation to ecological boundaries (Jill Read, Parks Victoria, pers.comm 2008).

Boundaries should not jeopardise the ecological requirement of niche specialists. These species have evolved through competition and require a stable environment. The Mistletoebird within the GGLMU is dependent upon the occurrence of mistletoe and will be affected by any event which threatens that resource.

Boundaries should not jeopardise the populations of spatially vulnerable species. Species with limited power of dispersal are less able to recolonise areas and may be more prone to local extinctions (including amphibians, reptiles and small-sized mammals). Within the GGLMU, the Smoky Mouse is one such example.

Boundaries should not jeopardise populations of disjunct species. These species are already under stress and are particularly susceptible to human induced modification (including prescribed burning). The Victoria Range and Mount William Range within the GGLMU represents the northern extent of the rare endemic Banksia saxicola within Victoria (Evans et al. 2001).

2.7.2 Biophysical Boundaries within the Greater Grampians LMU

Inferences from the literature suggest that the linear rocky escarpment (e.g. Victoria Range, Mt William Range) may provide a physical barrier to movement of small mammals associated with particular EVDs. Lindorff (1999) identified steep cliffs (i.e. rocky escarpment), reservoirs and streams as potential barriers to Heath Mouse dispersal in the Grampians and found that these barriers ran between heathland communities to provide obvious heathland sub-populations.

The spatial distribution of species records was used to elucidate potential divisions in occurrence across the Greater Grampians landscape. For fauna, a selection of species with known (or assumed) low movement capacity was used (e.g. Heath Mouse, Swamp Rat, Dusky Antechinus). In some cases, investigation of the spatial distribution of records using GIS show clear separations in populations, including for widely distributed species. As predicted, the linear rocky escarpment separated populations (i.e. database records) for a number of the selected species. However, the potential boundary effect of less prominent landscape features (i.e. streams, roads) did not appear obvious.

The biophysical boundaries proposed for the Greater Grampians LMU, in part, and not necessarily by design, also represent natural fire boundaries. Investigation of past fire events in the Greater Grampians LMU (including wildfire and prescribed burns) shows that for a considerable number, the fire boundaries align with rocky escarpments (see section 5). This phenomenon is assumed to be a function of the effect of the ridge line on fire behaviour.

2.7.3 Assumptions

The biophysical boundaries considered in this project represent potential boundaries for identified species. The boundaries defined herein are considered in terms of the individual species ability to cross these based on their movement/dispersal capability, habitat attributes and distribution within the Greater Grampians Landscape Management Unit. These boundaries are not proven (i.e. supported by quantitative research or genetic analysis).

Educated judgments, based on inferences from known information, have been made for a number of species where data relating to specific vital attributes was unknown or limited. It would be beneficial to conduct surveys within the Grampians LMU for identified KFRS to identify local distribution and population parameters, including genetic studies to elucidate relationships between separated populations in the landscape. This would provide a clearer picture of potential biophysical boundaries and how they function in the landscape.

2.7.4 Integration of potential biophysical boundaries and fire

Boundaries create sub-units and fire planning and management must be sensitive at a level to ensure that populations within sub-units are presented with a suitable fire mosaic and are not lost or negatively impacted by broad-scale burning as the functioning of biophysical boundaries substantially reduce recolonisation potential for some fauna.

As (largely) independent entities, each unit warrants specific fire prescriptions to maintain the viability of populations (within units) and the maintenance of landscape biodiversity (between units).

The logic behind identifying biophysical units for fire planning and management is a problem- solving approach to address the following; how can fire be effectively applied and managed to maintain the ability of species to persist (i.e. maintain viable populations) and retain spatial dynamism (i.e. not inhibit functional connectivity between usable parts of the landscape)? Following on from this we need to consider, at what level do we tolerate species loss? It may not be critical if a species is lost from one component of a biophysical unit if viable populations capable of recolonising the unit occur in a surrounding biophsyical unit. This approach may be adopted for more mobile species capable of easily permeating boundaries (e.g. some birds).

3. Stage 2 Creation and Rationale of Biophysical Units within the GGLMU

3.1 Development of Initial Biophysical Units

A number of natural features were investigated in the development of the biophysical units in the Greater Grampians landscape. This included landscape features (e.g. ridelines and escarpments, catchments and drainage lines), vegetation features (EVC and EVD) and species information (flora and fauna records).

An initial step in the development process was the investigation of the spatial distribution of species records for both flora and fauna. Records from the Flora Information System (FIS) and Atlas of Victorian Wildlife (AVW) were mapped for the Greater Grampians LMU. The FIS and AVW contain the most comprehensive accessible data on flora and fauna location records for Victoria. The landscape pattern of the records was examined to reveal potential divisions in occurrence across the landscape. The distribution records of rare or threatened species and potential Key Fire Response Species (see section 2.5) in particular were examined. Despite a relatively high number of records contained within these databases for the Greater Grampians LMU, the coverage of records was not consistent across the Greater Grampians LMU and few species had adequate records to facilitate a thorough and accurate assessment of their distribution in the Greater Grampians LMU. This compromised the ability to confidently use the spatial distribution patterns of flora and fauna species to delineate potential biophysical boundaries in the Greater Grampians LMU. To overcome this, an alternative approach was adopted using potential physical (i.e. ridgelines) and watershed boundaries. This approach has previously been used to delineate landscapes into biophysical units (e.g. Theberge 1989). The benefit of this approach is that such boundaries are likely to represent biophysical boundaries for flora and fauna in the landscape as well and therefore represent a viable alternative to the spatial distribution of species approach initially used.

The biophysical units were developed by first dividing up the Greater Grampians LMU based on large waterbodies (e.g. Rocklands Reservoir, Wartook Reservoir), streams, roads and ridgelines

(e.g. Victoria Range, Serra Range, Mt. William Range). These features were considered potential physical barriers to the movement of small mammals (e.g. McDonald and St. Clair 2004; Rico et al. 2007; see also Lindorff 1999). Less prominent landscape features including streams and roads were scrutinised against the spatial distribution of fauna records as a further measure to identify any evidence of potential barrier effects (i.e. distinct divisions of species records around potential barriers). There was no evidence of the potential barrier effect of roads or streams in the Greater Grampians LMU. Subsequently, only the ridge lines and Rockland Reservoir were tagged as potential physical barriers to small mammal movement within the Greater Grampians LMU.

In line with the literature (e.g. Omernik and Bailey 1997; Steiner 2000), the Greater Grampians LMU was then divided up into catchments and watersheds. The broadest catchment scale initially used was the pre-defined Glenelg / Wimmera catchment management boundary which divided the Greater Grampians LMU into two blocks (across the northern region). Sub-catchment boundaries, as identified by the Glenelg Hopkins CMA and the Wimmera CMA, were then mapped and incorporated into the spatial analyses. Eight sub-catchment boundaries were identified although only one sub-catchment, Fyans Creek, was deemed suitable to form a biophysical unit in-itself. An analysis of watersheds within the sub-catchments was then undertaken. A map of watersheds was created using a 50 m resolution digital elevation model (DEM) of the GGLMU (using IDRISSI) which was then opened in GRASS. The watershed basin analysis program (r.watershed) was run to generate the location of watersheds within the GGLMU at 1:10,000 scale. As the default option of this map is a raster image, the watershed map was converted to polygons using the rastor-to- vector program in GRASS (r.to.vect). The resulting watershed map was translated into a MapInfo file to use as a base to build up the biophysical units.

The initial biophysical units, therefore, were primarily developed by combining watersheds which fell between ridgelines and which were located in the same sub catchment. The Rocklands Reservoir was used to break up biophysical units in the west of the GGLMU, outside of the Grampians National Park. Additionally, the Moora channel was retained as a potential barrier, despite doubts on the effectiveness of the Moora channel to act as a barrier. At this stage, the EVDs had not been incorporated as a boundary factor. The Grampians National Park boundary

(20)

(19)

was considered relevant in some areas, however the development of the BPUs was mostly tenure blind across the public land in the Greater Grampians LMU.

The draft biophysical units are shown in the map titled Biophysical Units within the Greater Grampians Landscape Management Unit (located at the end of this report). To further investigate the applicability of the biophysical unit model proposed for the Greater Grampians LMU it is recommended that subsequent work be undertaken to examine the function of the proposed boundaries. This could be achieved using genetic analysis of selected flora and fauna populations, including those of Key Fire response Species, to examine patterns across the boundaries identified in this project.

3.2 Existing Data

The following table contains a list of data layers provided by Parks Victoria to the CEM to assist in the spatial analysis component of the project (Table 3-1).

Table 3-1List of data layers used in the Spatial Analysis component of the project supplied by Parks Victoria

Name of Data

Bioregions

Data Type

Vector - Polygon

Format

MapInfo

Location

State Wide

*Flora Information Systems (FIS)

Vector - Point Data

MapInfo

Cut to GGLMU with plant vital attribute information attached.

Atlas of Victorian Wildlife

Vector - Point Data

MapInfo

Cut to GGLMU

(AVW)

EVC_BCS100_10102006

Vector - Polygon

MapInfo

Cut to GGLMU

FIRE100

Vector Polygon

MapInfo

Cut to GGLMU

Hydro100

Vector Line

MapInfo

Cut to GGLMU

LastBurnt

Vector Polygon

MapInfo

Cut to GGLMU

Morphology

Vector Line

MapInfo

Cut to GGLMU

PLM100_Other

Vector Polygon

MapInfo

Cut to GGLMU

(Public Land)

Topo100

Vector Line

MapInfo

Cut to GGLMU

Tree100

Vector - Polygon

MapInfo

Cut to GGLMU

VicMap_contour

Vector Line

MapInfo

Cut to GGLMU

VicMap_hydro

Vector Line

MapInfo

Cut to GGLMU

VicMap_hydro_po

Vector Line

MapInfo

Cut to GGLMU

VicMap_roads

Vector Line

MapInfo

Cut to GGLMU

GlenelgCMA_MGA54

Raster

MapInfo

Cut to GGLMU

Wimmera_CMA

Raster

MapInfo

Cut to GGLMU

Grampians_22022006

Raster

MapInfo

Cut to GGLMU

Heath Mouse meta populations Grampians NP

Vector Polygon

MapInfo

Grampians National Park

BarriersVector Line/PolygonMapInfoGrampians National Park

* The FIS layer was provided to CEM with permission from Royal Botanic Gardens who are the custodians of the dataset. Vital Attribute Information was attached to this database by Parks Victoria for the express purpose of this project only.

(Stage 2 Creation and Rationale of Biophysical Units within the GGLMU)

Stage 2 Creation and Rationale of Biophysical Units within the GGLMU

3.3 Consultation with Parks Victoria and DSE

After the initial boundaries were developed, a workshop was held with relevant staff from Parks Victoria and the Department of Sustainability and Environment (DSE). The aim of the workshop was to incorporate local knowledge and expertise on the Greater Grampians region into the development of the biophysical boundaries, particularly on the behaviour of fire within the area. This workshop played a crucial role in developing the final boundaries. Table 3-2 outlines the changes made to the biophysical units on the advice of workshop participants. A list of participants is given in Appendix 6.

Table 3-2Changes to the biophysical units based on consultation with PV and DSE IssueAdvice / ReasoningAction

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The use of the Moora Channel as a barrier

Suitability of the South Grampians Unit as one unit

Incorporation of the smaller Mount William Range East unit into the Serra Range unit

Incorporation of EVD and EVC boundaries

Trapping for small mammals has been successful both sides of the Moora channel indicating that the Moora channel is not a barrier to movement.

South Grampians should be split due to environment / aspect with the east back slope of the Serra Range a dry environment. Additionally, there is no connectivity through the valley (farmland). For example, the Dusky Antechinus has been recorded in the Victoria Range but not on the west slope of the Serra Range.

The small size (4,898 ha) of the unit lead to concerns for its practicality. Additional factors included fire behaviour considerations and habitat connectivity of the Wannon River, given that this area was considered a low strength boundary.

The North West Victoria Range should be extended west towards the Rockland Reservoir to incorporate the Heathland (sands) EVD. The boundary of the Grampians National Park should be removed from consideration as is only a management construct.

The Western Plains Woodland EVD occurs primarily in one stand-alone block to the south of the Rocklands Reservoir. Therefore, this block was deemed suitable as a single biophysical unit.

The endemic Montane Rocky Shrubland EVC occurs on the junction of the Serra Range Unit (now Wannon System) and the Mount William Creek unit. It was considered appropriate that the boundary of the Wannon System be extended east to incorporate the entire EVC.

Moora channel removed as a boundary delineator. Glenelg River North and Glenelg River South biophysical units merged into one unit Glenelg River.

South Grampians split into two disjunct units. The small northern section which previously connected the two units was merged into the Glenelg River unit for practicality reasons.

The unit to the east of the Victoria Range was renamed Burnt Hut Creek while the unit to the west of the Serra Range was renamed Serra Range (the original Serra Range unit was renamed Wannon System see below).

Mt. William Range East unit merged into the Serra Range unit, Serra Range unit renamed Wannon System.

The boundary of the North West Victoria Range was adjusted to encompass the Heathland (sands) EVD.

The Western Plains Woodland biophysical unit was created. This unit was cut from the Rocklands Reservoir

East unit which it was originally

embedded in.

The Wannon System was extended 600 m to the east to cover the presence of Montane Shrubby Woodland EVC. This unit therefore, no longer runs on the watershed boundary to the east but on the boundary of the endemic EVC.

IssueAdvice / ReasoningAction

(Stage 2 Creation and Rationale of Biophysical Units within the GGLMU)

Dissolution of the North Central Grampians Unit

Black Range East and Rocklands Reservoir Central

The eastern edge of the North Central Grampians unit should be incorporated into the Glenelg River Unit based on main stream flow and a vegetation assemblage which is more associated with the shrubby Grampians vegetation complex rather than the more open Western Plains vegetation which occurs in this region

The general north aspect and open country from the escarpment of the Black Range State Park makes it logical to incorporate the western edge of the North Central Grampians unit into the Black Range East unit.

The Black Range East and Rocklands Reservoir Central units are similar in vegetation composition and are only separated by a road.

The North Central Grampians unit was dissolved. The northern channel of the Rocklands Reservoir was used to split the unit. The west side was incorporated into the Black Range East unit, while the north - eastern side was incorporated in the Glenelg River unit.

The south-eastern side was incorporated into the Rocklands Reservoir East on further advice.

The Rocklands Reservoir Central unit was merged into the Black Range East BPU.

3.4 Data storage

In fulfilment of licensing agreements, Flora Information Systems and Atlas of Victorian Wildlife data has been removed from CEM systems at project completion. All other mapping layers have been packaged and provided to Parks Victoria with this report.

4. Biophysical Units

A total of 15 biophysical units were identified within the Greater Grampians Landscape Management Unit, based on catchment and watershed mapping, the presence of ecological vegetation divisions and endemic ecological vegetation classes, and the presence of physical barriers to small mammal movement (e.g. ridge lines).

4.1 Biophysical units and ecological vegetation division composition

To distinguish relationships between BPUs in the Greater Grampians LMU a multi-dimensional scaling (MDS) ordination based on EVD composition was undertaken. The purpose of the MDS is to represent the samples (i.e. BPUs) in ordination space such that the relative distances apart of all points are in the same rank order as the relative dissimilarities of the samples (Clarke and Gorley 2001). The interpretation of the MDS is straightforward: points that are close together represent BPUs that are very similar in EVD composition; points that are far apart correspond to very different BPUs.

There is some clustering of sites in relation to proportion of BPUs covered by EVDs (Figure 4-1). The analysis stress value of 0.1 corresponds to a good ordination with no real prospect of a misleading interpretation (Clarke and Gorley 2001). BPU 5 was excluded from the analysis due to its unique characteristic of being almost entirely comprised of a single EVD, Western Plains Woodland. There were four obvious clusters of sites displayed in the MDS ordination. BPU 12 is clearly different to other BPUs. BPU 2 and BPU 4 form a cluster, as do BPU 9 and and BPU 3. The rest of the BPUs (BPU 1, BPU 6, BPU7, BPU 8, BPU 10, BPU 11, BPU 13, BPU 14 and BPU

15) form a larger cluster (Figure 4-1).

To interpret patterns in the clustering of BPUs in relation to each other in ordination space, a bubble-value was displayed for each EVD in relation to the overall landscape pattern (Figure 4-1). The bubble value shows the contribution that a particular EVD makes to a BPU and provides a useful tool to interpret the composition and similarities between BPUs.

BPU 12 stands out for the high proportion of damp vegetation communities it supports including Moist Forest, Riparian Forest, Tall Mist Forest, Tall Mixed Forest and High Altitude Shrubland/Woodland EVDs.

BPU 2 and BPU 4 are distinct in the Greater Grampians LMU due to the high proportion of Alluvial Plains Woodland EVD that they support. These BPUs were separated by the Rocklands Reservoir, which provides a potential physical barrier in the landscape.

BPU 3 and BPU 9 share distinct similarities including supporting the only Riverine Woodland / Forest EVD in the Greater Grampians LMU, as well as Treed Swampy Wetland EVD and Freshwater Permanent Wetland EVD. BPU 3 supports the only Saline Wetland EVD recorded for the Greater Grampians LMU. Both BPUs are linked to the Glenelg River. BPU 9 (Glenelg River) contains the upper catchment of the river while BPU 3 (Rocklands Reservoir West) is located in the far west of the Greater Grampians LMU where the Glenelg River flows from Rockland Reservoir.

The cluster formed by BPU 1, BPU 6, BPU 7, BPU 8, BPU 10, BPU 11, BPU 13, BPU 14 and BPU

15 support a diverse range of EVDs. Rocky Knoll EVD is generally a prominent component of these BPUs, as well as Grassy / Heathy Dry Forest EVD and to a lesser extent Heathland (sands) EVD. Damp Scrub EVD is a component of all BPUs in this cluster. Forby Forest EVD and Tall Mixed Forest EVD occur in most BPUs in this cluster. Some EVDs restricted to one or two BPUs in the Greater Grampians LMU occur in this cluster including High Altitude Wetland (BPU 14) and Freshwater Wetland (BPU 14 and BPU 11). Apart form BPU 5, BPU 11 supports the only occurrence of Western Plains Woodland in the Greater Grampians LMU.

This analysis lends support to adopting similar management approaches for BPUs in the identified clusters based on similar compositions of EVDs.

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Alluvial Plains Woodland

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Damp Scrub

(Biophysical Units)

(Biophysical Units)

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Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Foothill Forest

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Forby Forest

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Freshwater Wetland (Ephemeral)

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Freshwater Wetland (Permanent)

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Grassy / Heathy Dry Forest

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Heathland (sands)

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

High Altitude Shrubland / Woodland

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

High Altitude Wetland

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Moist Forest

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Riparian Forest (higher rainfall)

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Riverine Woodland / Forest

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Rocky Knoll

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Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Saline Wetland

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Tall Mist Forest

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Tall Mixed Forest (eastern)

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Treed Swampy Wetland

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

Western Plains Woodland

Stress: 0.1

B15

B1

B7

B11

B13B2

B8

B10

B14B4

B12

B6

B3 B9

N/A

Figure 4-1 Ordination of the ecological vegetation division composition for biophysical units in the Greater Grampians landscape management unit (Stress 0.1).

The contribution of each EVD in alphabetical order is displayed separately.

5. Strength of biophysical unit boundaries

The proposed biophysical unit boundaries identified for the Greater Grampians LMU are physical landscape factors that potentially limit species movement or dispersal through the landscape, effectively creating independent units (e.g. meta-population model). It is important to understand that the boundaries considered are landscape scale factors, and that at the local scale these boundaries may, or may not, have properties that affect their permeability.

The nature of a boundary is likely to vary across the landscape. For example, a prominent rock face forming part of the rocky escarpment (e.g. parts of Serra Range) is expected to provide a sharp, impermeable boundary (i.e. high strength boundary). Altenatively, a plateau area along a rocky escarpment is expected to provide a less distinct, permeable boundary at the local site level

1.e. low strength boundary). Such boundaries are likely to have properties of ecotones where at a local scale boundaries are likely to be fuzzy and exist as a gradient over some distance (up to several hundred metres). An example of such a boundary occurs along the Mt William Range escarpment separating BPU 13 and BPU 14.