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4. Threatened ecosystems and species

Summary

For the purposes of the Terrestrial Biodiversity Assessment, an ecosystem is defined as an integrated unit of vegetation, including dominant species and structural formation, underlying geology or soils and land form. The conservation status of ecosystems has been determined by comparing remnant extent and change in condition with pre-clearing extent across either the distributional range of the ecosystem or its bioregional occurrence. Threatened ecosystems include both endangered and vulnerable ecosystems.

Approximately 2891 threatened assemblages, including 2859 ecosystems and 32 other ecological communities, are identified in the first attempt to systematically determine the conservation status of Australia's terrestrial ecosystems. The scale of identification of threatened ecosystems varies across bioregions according to the ecosystem and vegetation mapping available.

In terms of the broad vegetation classes in which these threatened assemblages belong, 15% are eucalypt forests with a shrubby understorey, 12% are eucalypt woodlands with a shrubby understorey and 11% are eucalypt woodlands with a grassy understorey. Eucalypt woodlands are the most extensively cleared vegetation group in Australia.

Threatened ecosystems occur across much of Australia. Most bioregions (94%) have one or more threatened ecosystems. More than half of the total number of ecosystems in bioregions are threatened on the central east coast, the Darling Riverine Plains, the Murray Darling Depression, and other parts of New South Wales. This represents 16% of the 62 bioregions where information is available to calculate the percentage threatened in relation to the total number of ecosystems. A large proportion of bioregions (39%) have more than 30% of their total ecosystems threatened.

The number of threatened species of flora and fauna, including non-vascular and invertebrate species, ranges up to 236 per subregion, with the highest numbers in parts of the Murray-Darling Basin, the developed coastal parts of eastern and southern Australia, parts of Tasmania and in south-west Western Australia.

The most common threatening processes for threatened species are vegetation clearing, particularly in Queensland and New South Wales, continuing loss of native vegetation in Tasmania, increased fragmentation of vegetation remnants in New South Wales and south-western Australia, overgrazing and feral animals across much of central and western Australia, inappropriate fire regimes in northern Australia, and changed hydrology from various causes.

Similar processes affect threatened ecosystems. Vegetation clearing and increased fragmentation of vegetation remnants are the most significant threats in eastern Australia. Additional threatening processes are firewood collection in parts of southern Australia, salinity and other changed hydrology and exotic weeds.

The report to the Prime Minister's Science, Engineering and Innovation Council (Morton et al. 2002) recommended that reducing land clearing is one of the four areas of investment above all others that is likely to return greatest impact in heading off the diminishing values of Australia's natural systems and biodiversity.

This Biodiversity Assessment confirms that it is imperative that action be taken to limit vegetation clearing to ensure that regional biodiversity and hydrological objectives are not further compromised.

Introduction

Threatened species and communities receive considerable attention in the conservation debate. All States and Territories maintain lists of flora and fauna species that require special protection and have legislation to promote improved management. Generally, the objectives are to prevent extinction and to restore viable populations.

While it is important to manage individual threatened species in order to conserve the many components of biodiversity, including the thousands of species of invertebrates, non-vascular plants and microorganisms, it is far more cost-effective to prevent species from becoming threatened by conserving them as part of viable and functioning ecosystems.

Recently, the focus on species conservation has broadened to the identification and conservation of threatened ecosystems. The governments of the Commonwealth, Australian Capital Territory, New South Wales, Victoria and Western Australia have enacted legislation to protect threatened ecological communities or ecosystems and Queensland has legislation to protect endangered regional ecosystems specifically from clearing. While detailed assessments of the conservation status of individual groups such as birds (Garnett & Crowley 2000) can be used to identify species that should receive special protection, no equivalent assessments have been available at the national level for threatened ecosystems.

One of the significant outputs of the Biodiversity Assessment is a list of threatened ecosystems across Australia together with a recommended conservation status of endangered or vulnerable. The trend of threatened ecosystems and species was also examined. Extensive information on threatening processes has been collated for both species and ecosystems at a subregional scale.

The Assessment

Threatened Ecosystems

For the purposes of the Terrestrial Biodiversity Assessment, ecosystems are described as integrated units of vegetation including the dominant species in the principal stratum and structural formation, geology or soils and landform. Each State and Territory was asked to identify threatened ecosystems across their bioregional distribution. Threatened ecosystems were recommended as either endangered or vulnerable as per criteria for assessing threatened ecological communities pursuant to the Environment Protection and Biodiversity Conservation Act 1999 (Commonwealth). The reliability of this assessment was recorded.

To assist in understanding the broad patterns of threatened ecosystems, the ecosystems were related to the 44 National Vegetation Information System (NVIS) Major Vegetation Sub-groups. This grouping will assist in the assessment of appropriate conservation measures for groups of threatened ecosystems. Any existing listings under State, Territory or Commonwealth legislation has been recorded.

The trend of the threatened ecosystem and what processes threaten each ecosystem has been assessed at a subregional scale. Trend for both threatened ecosystems and species was ranked in terms of six categories:

1. extinction, e.g. targeted research has not observed the species in recent times or no record of the species in the last 20 years
2. status/condition rapidly declining, e.g. less than 10 year time frame
3. status/condition declining
4. status/condition static
5. status/condition improving
6. unknown

Although threatened ecosystems were identified across most bioregions, it was not possible to calculate a percentage in all bioregions. Ecosystems have not been comprehensively mapped for some bioregions at the same scale as used in the identification of threatened ecosystems. The scale of vegetation mapping also varies across States and Territories and this has influenced the number of threatened ecosystems recorded in various bioregions.

Lists of threatened ecosystems were made for those bioregions which cross State and Territory borders by the jurisdiction containing the principal part of the bioregion and in consultation with the neighbouring jurisdiction. Cross-border issues arose in a number of locations where ecosystems were identified at different scales and further work is required to develop consistency in these situations.

Threatened Species

Each State and Territory provided a description of the trend in status and condition of threatened species or groups listed by the Commonwealth, States and Territories. Threatening processes were identified for threatened species in each subregion where known. The reliability of the assessment of trend was ranked for each threatened species or group. To aid in recovery planning, it was proposed that threatened species be allocated to groups, either on the basis of similiar location, ecological requirements, or other factors that would enable the requirements for a group of species to be considered together. However, this could not be treated in a comprehensive way in this assessment.

The frequency of the 12 threatening processes on both threatened ecosystems and species was recorded for each subregion (see Figure 2.2 for the 12 threatening processes).

This extensive information on both threatened ecosystems and species is reported on the Australian Natural Resources Atlas for all bioregions and subregions.

Findings

Threatened Ecosystems

There are 2891 threatened assemblages in Australia. Of those, 2859 are threatened ecosystems and a further 32 other ecological communities such as stygofauna communities are threatened. Ten bioregions have greater than 50% of ecosystems threatened - Central Mackay Coast, South Eastern Queensland, New South Wales North Coast, Nandewar, New England Tableland, Sydney Basin, South East Highlands, Darling Riverine Plains, Victorian Volcanic Plain and Murray Darling Depression (Figure 4.1).

These represent 16% of the 62 bioregions where data were available to determine a percentage of the total number of ecosystems occurring in a bioregion. The bioregions correspond to the extensively cleared parts of eastern Australia and within the Murray-Darling Basin with clearing still occurring in many of these bioregions. A further 14 (23%) of these 62 bioregions have between 30% and 50% of their total ecosystems threatened.

It is likely that with the availability of comprehensive bioregional data for South Australia and other parts, that additional bioregions will be identified as having a higher proportion of threatened ecosystems.

In the more extensively used landscapes in northern and western Australia, large numbers of threatened ecosystems are identified primarily due to grazing pressure and changed fire regimes.

The extent of this biodiversity decline at an ecosystem level has major ramifications in terms of future species loss and impacts on ecological processes and ecosystem services.

Available on the Atlas is a comprehensive listing of all threatened ecosystems by bioregion. Table 4.1 is an extract from the Atlas and lists threatened ecosystems for the Riverina bioregion, the reliability ranking associated with their identification, the NVIS Major Vegetation Subgroup that each ecosystem belongs to, whether the ecosystem is already listed under State, Territory or Commonwealth legislation, their recommended status (endangered or vulnerable), and their trend in condition.

Table 4.1: Extract of an Atlas table listing threatened ecosystems for the Riverina bioregion: their reliability of the identification, Major Vegetation Subgroup, current legislative protection, recommended status and trend.

THREATENED ECOSYSTEM	RELIABILITY OF THE IDENTIFICATION	MAJOR VEGETATION SUBGROUP	EPBC LISTING	STATE LISTING	RECOMMENDED STATUS	TREND
Lignum Wetland	Quantitative and qualitative	Herbland, Sedgeland and Rushland		E	E	Declining
Pine Box Woodland	Quantitative and qualitative	Eucalyptus woodlands with a grassy understorey	E	E	E	Declining
Pine Buloke Woodland	Quantitative and qualitative	Callitris forests and woodlands	E	E	E	Unknown
Plains Grassy Woodland	Quantitative and qualitative	Eucalyptus woodlands with a grassy understorey		E	E	Declining
Red Gum Wetland	Quantitative and qualitative	Eucalyptus woodlands with a grassy understorey		E	E	Declining
Riparian Woodland	Quantitative and qualitative	Eucalyptus woodlands with a shrubby understorey		E	E	Declining
Riverine Escarpment Scrub	Quantitative and qualitative	Tall shrublands		Extinct	Extinct	Extinction
Riverine Grassy Woodland	Quantitative and qualitative understorey	Eucalyptus woodlands with a grassy		V	V	Declining
Sand Ridge Woodland	Quantitative and qualitative	Callitris forests and woodlands		E	E	Declining
Sedge-rich Woodland	Quantitative and qualitative	Eucalyptus woodlands with a grassy understorey		E	E	Declining
Note: E denotes endangered and V denotes vulnerable

National Vegetation Information System

Each threatened ecosystem was matched to a Major Vegetation Subgroup of the National Vegetation Information System (NLWRA 2001c) in order to provide a picture of the types of ecosystems that are threatened across Australia (Table 4.2). This approach can help identify groups of threatened ecosystems and make conservation management more strategic.

The result of the matching is that eucalypt forests and woodlands are the dominant types of threatened ecosystems. One thousand, two hundred and thirty-eight of the threatened ecosystems (about 43% of the total) are eucalypt dominated forests or woodlands with a shrubby or grassy understorey.

Table 4.2: The number of threatened ecosystems in each of the 44 Major Vegetation Subgroups identified in the National Vegetation Information System (NLWRA 2001c).

NATIONAL VEGETATION INFORMATION SYSTEM MAJOR VEGETATION SUBGROUPS	NUMBER THREATENED ECOSYSTEMS
Eucalyptus forests with a shrubby understorey	425
Eucalyptus woodlands with a shrubby understorey	344
Eucalyptus woodlands with a grassy understorey	318
Eucalyptus forests with a grassy understorey	149
Herbland, sedgeland and rushland	137
Tropical and sub-tropical rainforest + dry rainforest	136
Other tussock grasslands	123
Other grasslands	114
Tall shrublands	97
Heath + Banksia woodlands and shrublands	67
Brigalow (Acacia harpophylla) forests and woodlands	60
Other shrublands	51
Arid Eucalyptus low open woodlands with tussock grass	44
Eucalyptus tall open forest and Eucalyptus forests with a dense broad leaved understorey (wet sclerophyll)	43
Melaleuca forests and woodlands	44
Other Acacia forests and woodlands	43
Casuarina and Allocasuarina forests and woodlands	42
Other forests and woodlands	36
Tropical mixed spp forests and woodlands	32
Mixed Chenopod, Samphire and Forblands	45
Callitris forests and woodlands	28
Alpine and sub-alpine woodlands, shrublands, sedgelands and herbfields	28
Bare areas, rock, sand, claypan, salt lakes and lagoons	28
Mangroves, tidal mudflat and coastal samphire	27
Freshwater lakes	28
Arid Acacia low open woodlands and shrublands with chenopods	26
Mixed species arid Acacia woodlands and shrublands	25
Cool temperate rainforest	25
Chenopod shrublands	25
Mulga (Acacia aneura) woodland and low open woodland	23
Eucalyptus forests with a heath understorey	21
Other low open woodlands and shrublands with tussock grass	19
Mallee Eucalyptus low open woodlands	17
Arid acacia low open woodlands and shrublands with tussock grass	16
Arid Eucalyptus low open woodlands with hummock grass	12
Mallee heath and shrublands	7
Spinifex hummock grasslands	7
Arid Acacia low open woodlands and shrublands with hummock grass	5
Low tropical Eucalyptus forests and woodlands	4
Blue Grass (Dichanthium) and Tall Bunch Grass (Chrysopogon) tussock grasslands	2
Tropical Eucalyptus forest and woodlands with a annual grassy understorey	2
Mitchell Grass (Astrebla) tussock grasslands	1
Note: Data was not available for 104 ecosystems and 61 ecosystems fell into the category of 'unclassified native vegetation'.

Threatening Processes

The most widespread processes threatening ecosystems are vegetation clearing, fragmentation of remnant vegetation, grazing pressure, exotic weeds, feral animals, firewood collection, salinity and other changed hydrology, and altered fire regimes.

Clearing and increased fragmentation of remnants are the principal factors threatening ecosystems in eastern Australia and other locations (Figure 4.2). There are exceptions to these general patterns and therefore these threatening processes cannot be ignored in the rest of Australia. For example, clearing threatens ecosystems near Darwin and is related to developments for horticulture and improved pastures.

The legacy of broad-scale clearing in southern Australia is widespread land degradation and loss of biodiversity. In areas that have already been subject to clearing, increased fragmentation and removal of small patches of remnant native vegetation can have major impacts on the plant and animal species as habitat falls below critical thresholds.

Salinity and firewood collection are mainly affecting ecosystems of southern and eastern Australia (Figure 4.2). Recognition that firewood collection is a major threatening process has only occurred in the last few years (Wall 2000; Driscoll et al. 2000) and has led to the formulation of a national framework for managing its impacts on conservation values and air pollution (ANZECC 2001b).

Overgrazing threatens ecosystems across much of Australia (Figure 4.2) and can lead to irreversible loss of protective soil crusts, decline in perennial grasses, change in composition of functionally important flora and loss of soil fertility (Woinarski 2001). The Australian Collaborative Rangeland Information System (NLWRA 2001d) proposes a framework to monitor rangeland condition, including biodiversity. In regions where major soil loss and extensive floristic change has not occurred, grazing impacts can be more easily addressed compared with the major revegetation required in southern and eastern Australia. Strategic fencing and improved stock management may enable paddocks to be rested at critical times and grazing regimes could be altered to favour biodiversity values.

Changed fire regimes threaten ecosystems across Australia and is one of the principal threats in northern Australia (Figure 4.2). Fire monitoring using remote sensing is helping to refine the management of fire in northern ecosystems (Russell-Smith et al. 2002). However, no systematic framework exists for addressing fire regimes in the fragmented ecosystems of southern and eastern Australia (Bradstock et al. 2002) and the use of remote sensing is complicated by cloud cover and more complex topography. Possingham et al. (2002) estimated that implementing fire management regimes in native vegetation would save 95 species per $1 million spent and that large collateral benefits would result.

In the rangelands, the loss of the soil crust, compaction and the formation of hard pans have had major impacts on the flow of water, and water holding capacity is reduced (Figure 4.2). The loss of mammals that traditionally dug up soils, such as the Burrowing Bettong (Bettongia lesueur), also has had an impact on water balance in the landscape, as well as on other elements of environmental health and function (Noble et al. 1999). Changes in the fire regime can have negative impacts on surface water flow, which in turn can affect the habitat of endangered species such as the Giant Desert Skink or Tjakara (Egernia kintorei). Overall, the impact of land uses on soil characteristics and biota requires further study.

Exotic weeds and feral animals have an impact on threatened ecosystems across many bioregions (Figure 4.2). These threatening processes are difficult and expensive to manage across large areas.

Available on the Atlas is detailed information on specific threatening processes for each threatened ecosystem in each subregion. Table 4.3 is an extract from the Atlas showing the level of data collated for each subregion.

Distribution of all threatening processes have not been mapped in Figure 4.2, however, some threatening processes may be regionally significant. For example, Jarrah dieback from Phytophthora cinnamomi is one of the significant threats to ecosystems at risk in southwest Western Australia.

Table 4.3: Extract of an Atlas table listing threatened ecosystems in the Tasmanian West bioregion; their recommended status, and threatening processes.

THREATENED ECOSYSTEM	RECOMMENDED STATUS	THREATENING PROCESS	NOTES
BA - Brookers gum wet forests	V	Other - describe	Clearing for forestry plantation establishment
F - king billy/pencil pine/ deciduous beech forest	V	Changed fire regimes	Ecosystem is fire sensitive
G - white gum/blue gum coastal forests on sands	V	Broad scale vegetation clearing	Clearing for agriculture or other purposes; weed invasion, dieback, inappropriate fire regimes, firewood collection
Ma - coastal saltmarsh	V	Grazing pressure
Mg - coastal saline rushland/ sedgeland	V	Grazing pressure
Ms - succulent coastal herbfield and saltmarsh	V	Grazing pressure
NP - native olive/blanket leaf shrubberies	E	Changed fire regimes	Ecosystem is fire-sensitive
Sd - Sand dune vegetation	-	Changed fire regimes
Waf - freshwater aquatic herbland	-	Increasing fragmentation and loss of remnants; grazing pressure; exotic weeds
X - king billy/pencil pine forests	V	Changed fire regimes	Ecosystem is fire-sensitive
Note: E denotes endangered and V denotes vulnerable

Frequency of Threatening Processes

To better understand the localised impact of each threatening process on ecosystems, the frequency of threatening processes recorded for each subregion was calculated. As it has not been possible in this assessment to indicate the relative importance of each threatening process on threatened ecosystems, these diagrams should only be interpreted as the frequency of threatening processes recorded.

Figure 4.3 shows the frequency of threatening processes recorded in two bioregions, Brigalow Belt North and Eyre Yorke Block. The remainder of the bioregions are available on the Altas. The two bioregions chosen to illustrate the range of processes impacting on threatened ecosystems provide an interesting contrast. In the Brigalow Belt North bioregion, vegetation clearance, increasing fragmentation of remnants, grazing pressure, changed fire regimes and exotic weeds have been identified as the main threats in all subregions. Salinity has only been noted as a minor component in two of the 14 subregions. In contrast, in the Eyre Yorke Block bioregion, where the history of development is much older, salinity has been recorded as a large component in four of the five subregions. Grazing pressure and weeds are common threats, reinforcing once again their widespread and pervasive nature.

Threatened Species

As of June 2002, the total number of threatened species listed under the Environment Protection and Biodiversity Conservation Act 1999 was 1595, comprising 346 vertebrates, 8 invertebrates and 1241 plants. To effectively plan their conservation it is important to know their distribution and threats in different parts of the landscape. The approach taken was to consider the number of threatened species occurring at both the bioregional and subregional scale.

The number of species listed as threatened at the bioregional level has been collated from both State and Territory legislative listings and from the Commonwealth indicative distribution maps. This information is provided in the bioregional summaries on the Atlas. An example bioregional summary is given in Table 4.4. Of particular note is the difference between State and Territory listings and the Commonwealth listing. This difference arises out of the different methodologies, where the Commonwealth used expert-validated modeled distributions rather than actual point location records. Reference to both data sets is desirable in regional planning to assess conservation needs for threatened species located in that subregion or bioregion and to assess whether the species occurs in terms of potential distribution.

Table 4.4: Extract of Atlas information on threatened species in the Ord Victoria Plain bioregion. Threatened species are by major groups and as listed by the Northern Territory and identified in the Commonwealth indicative distribution maps

SPECIES	COMMONWEALTH LISTING	STATE LISTING
Mammals
Lagorchestes conspicillatus conspicillatus (Spectacled Hare-wallaby (Barrow Island))	V	WA (V)
Macrotis lagotis (Greater Bilby)	V	NT (V); WA (V)
Rhinonicteris aurantius (Orange Leaf-nosed Bat)	-	WA (V)
Lagorchestes conspicillatus (Spectacled Hare-wallaby)	V	WA (V)
Macroderma gigas (Ghost Bat)	V
Birds
Erythrura gouldiae (Gouldian Finch)	E	NT (V); WA (E)
Geophaps smithii smithii (Partridge Pigeon (eastern))	V	WA (V)
Erythrotriorchis radiatus (Red Goshawk)	V	NT (V); WA (V)
Falcunculus frontatus whitei (Crested Shrike-tit (northern), Northern Shrike-tit)	V	NT (E)
Malurus coronatus coronatus (Purple-crowned Fairy-wren (western))	V	WA (V)
Reptiles
Crocodylus johnstoni (Freshwater Crocodile)	-	WA (V)
Vascular plants
Platysace saxatilis	-	NT (V)
Kohautia australiensis	-	WA (V)
Trianthema kimberleyi	-	WA (V)
Adiantum capillus-veneris (Dainty Maidenhair, Venus-hair Fern)	-	NT (V)
Note: V denotes vulnerable and E denotes endangered

The number of threatened species recorded at the subregional scale is indicated in Figure 4.4. This is based on State and Territory listings of threatened species and ranged from 0 to 236 species per subregion. The highest number occurs in the Murray Mallee subregion in north-western Victoria. Other subregions in Victoria also have very high numbers of threatened species, particularly subregions of the Murray Darling Depression, Victorian Midlands, South East Highlands, Victorian Riverina, South Coast Plain and Victorian Volcanic Plains bioregions. These equate mostly with highly cleared regions, apart from Murray Darling Depression 4—the subregion associated with the Big and Little Desert National Parks. South-east Tasmania and the New South Wales north coast also have greater than 150 threatened species per subregion.

The geographic patterns for threatened species are similar to those seen for threatened ecosystems. The subregions associated with the highly cleared areas of southern and eastern Australia have the highest numbers of threatened species. Only eight of the 384 subregions in Australia have no recorded threatened species.

This analysis gives no indication of whether a species was present in a subregion but is now extinct, a common situation in the more arid areas as discussed in the mammal chapter. Some locations with high numbers of threatened species may reflect historic refugia rather than the direct result of anthropogenic factors e.g., Cape York Peninsula.

Overall, the Murray-Darling Basin, coastal parts associated with intensive development, parts of Tasmania and the south-west of Western Australia are the areas most important in terms of threatened species.

Trend in Threatened Species

The trend in threatened species status or condition has been examined for species groups. Figure 4.5 shows the median trends for vascular plants, mammals, birds, reptiles and amphibians. The status of threatened vascular plants is declining across much of the continent (177 of the 384 subregions), as are threatened birds (240 subregions) with extinctions in arid parts of Western Australia (14 subregions).

Threatened mammal species are rapidly declining in 20 subregions and declining in 174 subregions, particularly in arid parts of Western Australia. Reptiles are declining across 119 subregions. Threatened amphibians are declining in southeastern Australia (65 subregions) and are rapidly declining in South East Queensland, Brigalow Belt South and Wet Tropics bioregions.

Little information was recorded for non-vascular plants and invertebrates reflecting not only the paucity of information but the limited protection afforded in State and Territory legislation. For example, the decline in land snails in Tropical Savannas has not yet been reflected in State or Territory listings of threatened species. Where information was available, decline in status was recorded. These species groups should be more comprehensively assessed.

Threatened species, or groups, are recorded on the Atlas for each subregion together with their status, trend, threatening processes and a reliability ranking of the assessment of trend.

Threatening Processes

With the extent of information collated on threatening processes impacting on the large number of threatened species, it has been possible to derive an overall map of the most common threatening processes by subregion (Figure 4.6).

This map illustrates the major biodiversity issues across Australia with:

• extensive vegetation clearing in Queensland, New South Wales and Tasmania;
• increased fragmentation of remnants in New South Wales and Western Australia;
• high continuing loss of native vegetation in Tasmania relative to its area;
• overgrazing in many parts of the pastoral zone;
• the widespread impact of feral animals in arid areas;
• changed fire regimes in northern Australia (being also significant on Cape York Peninsula);
• changed hydrology ranging from dams in Tasmania to the concentration of artificial watering points on the Barkly Tableland and to the impact on artesian springs in the Desert Uplands; and
• salinity emerging as the most common threat in parts of southern Australia.

The distribution of each threat contributing to the decline of threatened species in each subregion is detailed in Figure 4.7. These individual maps of each threat show the widespread nature of all 12 categories of threat identified as part of the template used in this assessment.

The specific information behind these maps is available on the Atlas. An example of this information is given in Table 4.5, which shows the threatened species or species group in each subregion, their status, trend, threatening processes, subregional distribution of the species and a reliability ranking of the assessment of trend.

The interpretation of all maps should be carried out in consultation with these tables on the Atlas to more fully gain and understanding of the issues identified. For example, the identified impact of pollution on remote coastal parts of the Northern Territory refers to marine debris affecting threatened turtle species.

Table 4.5: An extract from the Mallee 2 subregion table available on the Atlas.Threatened species, their status, trend and threatening processes. The reliability of the assessment of trend is indicated.

SPECIES	COMMONWEALTH LISTING	STATE LISTING	RECOVERY PLAN	TREND	RELIABILITY ASSESSMENT	THREATENING PROCESS
Mammals
Dasyurus geoffroii (Chuditch, Western Quoll)	V	V	No	Improving	Quantitative and qualitative	Broad scale vegetation clearing; increasing fragmentation and loss of remnants; feral animals
Macrotis lagotis (Greater Bilby)	V	V	No	Extinction
Myrmecobius fasciatus (Numbat)	V	V	No	Unknown	Quantitative and qualitative	Broad scale vegetation clearing; increasing fragmentation and loss of remnants; feral animals
Birds
Amytornis textilis textilis (Thick-billed Grasswren (western)	V	V	No	Extinction	Quantitative and qualitative
Calyptorhynchus latirostris (Carnaby's Black-Cockatoo, Short-billed Black- Cockatoo)	E	E	No	Declining	Quantitative and qualitative	Broad scale vegetation clearing; increasing fragmentation and loss of remnants; feral animals; changed hydrology - salinity and other
Vascular plants
Acacia auratiflora (Orange-flowered Wattle)	E	E	No	Rapidly declining	Quantitative and qualitative	Broad scale vegetation clearing; increasing fragmentation and loss of remnants; feral animals; changed hydrology - salinity and other; changed fire regimes
Acacia depressa (Echidna Wattle)	V	E	No	Declining	Quantitative and qualitative	Broad scale vegetation clearing; increasing fragmentation and loss of remnants; feral animals; changed hydrology - salinity and other; changed fire regimes
Note: V denotes vulnerable and E denotes endangered.

The frequency of threatening processes impacting on threatened species in each subregion has been collated and the Mallee and Flinders Lofty Block bioregions are used as examples (Figure 4.8).

Frequency pie diagrams of threatening processes are available for all 85 bioregions on the Atlas. As indicated for threatened ecosystems, these diagrams should not be interpreted as the relative importance of each threat.

Conclusions

The extent of landscape modification in Australia means that 2891 ecosystems and other ecological communities are now threatened. These assemblages are a priority for conservation to protect the immense species diversity associated with them and for the protection of ecological processes.

The threatened ecosystems and other ecological communities identified in this assessment provide a basis for targeted initiatives in biodiversity management. It is imperative that conservation is approached in a cost-effective manner and this analysis of threats to ecosystems and species at both the continental and regional scale provides a basis for strategic approaches to threat abatement. Specifically, the detailed information on the Atlas is a vital resource for focusing regional planing and management.

There are many management responses to the conservation of threatened ecosystems. One response could be listing threatened ecosystems under Commonwealth, State or Territory legislation where such provisions exist. Should this course of action be chosen, the information on threatened ecosystems in this report needs to be value-added, including the desirable scale for grouping ecosystems, and to further assess the equivalency of ecosystems and status across State and Territory borders.

The report to the Prime Minister's Science, Engineering and Innovation Council (Morton et al. 2002) urges that we protect and maintain our natural systems rather than be faced with an ever increasing repair bill. The high number of threatened ecosystems identified in this assessment indicates how extensive the repair task will be unless comprehensive action is taken.

In accord with the findings of the report to the Prime Minister's Science, Engineering and Innovation Council, urgent action is required to halt the clearing of all threatened ecosystems as well as broad-scale clearing within the Murray-Darling Basin. Priority areas should also include any subregion containing less than 30% remnant vegetation (see Chapter 9) and where the clearing of areas may threaten regional biodiversity values, including hotspots, and ecosystem function.

The wide range of threatening processes means that a variety of approaches to the protection of biodiversity is needed for different parts of the country. Protection and recovery both through protected areas and across the wider landscape is discussed later in this report.

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