SoE 2009 > Biodiversity > 7.2 Native fauna and flora

7.2 Native fauna and flora

The diversity and richness of native species in New South Wales continues to remain under threat.

A general pattern of decline in biodiversity over the longer term is evident in changes to the extent and abundance of many native vertebrate species. However, at the same time, many resilient species have maintained their distributions, while a small number of adaptable species have flourished.

In terms of historical declines, birds have been relatively resilient compared with other vertebrate groups. However, over the shorter time frame of the past decade, the distribution of many birds has declined and the prospects for sustainability of many species are at risk. Predictably, the sustainability of most of the threatened species assessed is also at risk.

One additional species has been listed as presumed extinct since 2006. The number of threatened species has increased only slightly, whereas listed populations have increased by 20% and communities by 14%, largely as a result of listing previously unassessed entities.

The main threats to native vertebrate fauna are invasive species, particularly foxes and cats, and habitat loss. The main threats to vegetation communities and native flora are the clearing of native vegetation and incursion of invasive species, particularly exotic weeds and herbivores.

Significant legislative and policy reforms have been introduced over the past five years to enhance the protection of biodiversity, largely focused on improving habitat and addressing threats more broadly to benefit all species.

Practical outcomes are being achieved by directly addressing the main threats through effective conservation in reserves, better regulation of vegetation clearing, strategic control of priority invasive species and better management of land and water resources.

While there are some encouraging examples of population recovery, measures that influence changes in populations and the status of species generally require longer time periods to take effect.

Most species are not currently monitored systematically and a broader program to monitor a representative sample of species is needed for groups other than birds, in order to reliably detect changes in their status and trends.

NSW indicators

Notes: Terms and symbols used above are defined in About SoE 2009 at the front of the report.

Introduction

Biodiversity is the diversity of ecosystems, the species and populations they support and the genes they contain. It also encompasses the complex interactions between living organisms and the environment which provide the basis for a range of ecosystem services and maintain the health and productivity of our landscapes. NSW has a rich biodiversity, much of which is recognised as internationally significant.

However, it is seldom possible to monitor or report on biodiversity across its breadth (Saunders et al. 1998). This theme is largely constrained to addressing native animal and plant species, particularly terrestrial vertebrates and those species of native plants listed under the Threatened Species Conservation Act 1995 (TSC Act), due to the sparsity of data for other groups. While information on some individual species of native plants, invertebrates and microorganisms may exist, broad statewide information providing systematic coverage of groups as a whole is limited to native vertebrate fauna and threatened species. Even for these groups the data is seldom collected systematically and there are significant gaps in overall coverage.

Comprehensive information on changes to the extent and abundance of vertebrates and some threatened plants has recently been compiled. Analysis of this data has enabled reporting of some changes and patterns in the status of species and some limited assessments of the future sustainability of species.

Status and trends

NSW has experienced declines and extinctions in a broad suite of native plants and animals since settlement (Dickman et al. 1993; Smith et al. 1994; Campbell 1999). Mammals have experienced the most significant declines with 26 of 138 species (19%) now extinct. In addition, 35 species of plants, 12 species or subspecies of birds, and one species each of reptiles, fish and invertebrates are also now listed as presumed extinct under threatened species legislation. Since SoE 2006, one additional species, the green sawfish (Pristis zijsron), has been listed as presumed extinct.

Native fauna

Historical declines

There were an estimated 897 species of native terrestrial vertebrates in NSW at the time of settlement. Changes in distribution since settlement (specifically losses) were estimated from species records for all terrestrial vertebrate species with adequate and reliable data (Figure 7.2).

To develop an understanding of the changing state of species diversity in NSW, current records (since 1995) of species distribution were compared with historical records of distribution (Mahon et al. in prep.). The assessment used all available data of sufficient quality from a range of sources. As no systematic monitoring was undertaken to generate this data, the coverage contains many gaps and may not be fully representative of missing species.

Changes in distribution over the past 230 years could be estimated with a reasonable level of confidence for about half of all terrestrial vertebrate species. Estimating distributional change for the remaining species is problematic because there is little or no historical data or because the available data is unreliable. Species such as microbats are often difficult to detect or have undergone recent changes in taxonomy.

Figure 7.2: Historical decline in the distribution of native terrestrial vertebrates

Source: DECC data 2008

Notes: Severe decline – change in distribution ≥50%
Moderate decline – 25–50% distributional change
No significant decline – change in distribution <25%

Approximately 4% of all native terrestrial vertebrate species in NSW are presumed to be extinct, while a further 7% of species (13% of those assessable) have lost at least half their former distribution. Mammals have fared poorly (Morton 1990; Dickman et al. 1993), with nearly one-fifth of all species presumed extinct and a further 10% of species (18% of those assessable) having lost at least half their distribution. The introduction of cats and foxes played a large role in early declines and extinctions of mammals (Dickman 1996a; Dickman 1996b; Smith & Quin 1996). All other taxonomic groups have suffered significant declines although no extinctions of amphibians have been recorded (Smith et al 1994; Campbell 1999). However, of all the vertebrate groups, birds have proven to be the most resilient.

Some species classified as showing no significant decline may have expanded in range since settlement, but the nature of the data prevents reliable assessment of range expansions. Nevertheless, range expansions of native fauna may have negative impacts on other native species and therefore would be unlikely to indicate an improvement in overall outcomes for biodiversity.

Sustainability of native fauna

The sustainability of native species refers to the likelihood of species persistence over future decades and has been assessed for terrestrial vertebrates using modified International Union for the Conservation of Nature (IUCN) Red-List criteria (IUCN 2001; IUCN 2008; Figure 7.3). In particular, estimates of total population size and distribution, trends in population size and distribution, and estimates of extinction risk from population modelling were used to assess the sustainability of each species. Species were only assessed if they are actively monitored at a regional or state scale and the data was sufficiently reliable. As a result, relatively few species have been assessed, but confidence in most of the assessments is good (Mahon et al. in prep).

Figure 7.3: Sustainability of native terrestrial vertebrates

Source: DECC data 2008

Just over a quarter of native terrestrial vertebrate species are monitored sufficiently in NSW to allow an assessment of sustainability at the statewide scale. The relatively large number of assessments of birds reflects the regular surveys conducted by Birds Australia for the Atlas of Australian Birds (Barrett et al. 2003). The limited data available for other groups is sufficient to reliably describe the status of the individual species, but is not representative of their taxonomic groups.

The sustainability assessments show that 64% of all fauna species that are assessable and 65% of birds have a moderate or greater risk of extinction (Mahon et al. in prep.). The data for birds, based on 217 species (48% of all species), reflects clearly detectable contractions in range over the past 10 years for a majority of the species assessed.

Prospects for the long-term sustainability of many of the bird species assessed are considered poor, and this data is the clearest evidence available that the decline in species appears to be ongoing. While there is insufficient data to describe recent trends in other vertebrate groups, there is little reason to expect outcomes to be dissimilar, especially as birds were the most resilient group in terms of historical declines (see Figure 7.2).

The assessments of historical decline and the sustainability of fauna species described above reveal widespread gaps in the availability of data and limited capacity to reliably detect changes in the status of, and particularly the ongoing trends in, species distribution and abundance. While it would not be feasible to monitor outcomes for all species, there is a clear need for broader monitoring of a representative range of species (not just vertebrate fauna), in order to reliably report changes in the status and trends of species diversity.

Native flora

Plant species diversity has declined significantly since settlement (Burgman et al. 2007), but there is little suitable data to quantify the rate or magnitude of decline. The decline is due to a range of pressures acting alone or in combination, including vegetation clearing and disturbance, heavy grazing and the impacts of invasive species.

Even where native vegetation remains, the richness of plant species may be diminishing. This is due to the fragmentation of populations in isolated communities which are unviable over the long term and are gradually being lost from the landscape. The simplification of species-level plant diversity has been recorded in many locations across Australia (Burgman et al. 2007).

Threatened species

Listed threatened species, populations and ecological communities

The TSC Act and Fisheries Management Act 1994 (FM Act) provide for the listing of threatened species (Table 7.3). Individual species, populations and ecological communities that are assessed as being at risk of extinction in NSW are listed, based on the threat categories outlined by the IUCN.

Table 7.3: Number of listed species, populations and ecological communities

Source: DECC data 2008 and DPI data 2009

Notes: Terrestrial data listed under the TSC Act as at 19 December 2008
Fisheries data listed under the FM Act as at 23 January 2009
^* From SoE 2006
^** Listed species or ecological communities only, excludes listed endangered populations
^*** Excludes endangered populations

At present a total of 957 species (including 77 that are presumed to be extinct), 46 populations and 91 ecological communities are listed as threatened. The number of species listings has risen only slightly since last reported in 2006, but there have been more substantial increases in the listings of populations (21%) and communities (14%). These changes primarily reflect the pattern of new listings for populations and communities that had not previously been assessed under the listing criteria of the relevant Acts.

Changes in the numbers of species, populations and ecological communities listed between reporting periods may therefore reflect changes in information rather than actual changes in the status of native flora and fauna (Keith & Burgman 2004). Many species are also not listed as vulnerable or endangered even though their abundance and range may be declining, as they are not considered to be under threat at present.

Historical declines in threatened species

Figure 7.4 shows that native species of terrestrial vertebrates listed as threatened have experienced greater range contractions than all terrestrial vertebrate species (Figure 7.2). This is not surprising since many of these species have been listed because they have experienced declines in distribution and abundance, in order that resources can be directed towards protecting them (see Responses). Only 30% of threatened invertebrate species have been studied sufficiently to allow an assessment of trends over the past 200 years, but the majority of these have also experienced severe declines (Mahon et al. in prep).

Figure 7.4: Historical declines in threatened native animals, plants and ecological communities

Source: DECC data 2008

Notes: Severe decline – change in distribution ≥ 50%
Moderate decline – 25–50% distributional change
No significant decline – change in distribution < 25%

The methods to assess historical decline were developed specifically for fauna species, as records of flora species have generally not been collected with the same level of consistency over the past 200 years. However, where the data allows, these methods have also been applied to threatened flora species and ecological communities. The available data for flora reveals a similar pattern of decline to the fauna data described previously (Mahon et al. in prep; Figure 7.4).

As expected, most of the threatened ecological communities for which data is available have also experienced substantial declines in range. These communities are generally defined on an ad hoc basis when they undergo assessment for listing, so the data available is likely to selectively describe communities that are subject to a degree of threat.

Sustainability of threatened species

As for terrestrial vertebrates (Figure 7.3), the sustainability of threatened flora and fauna in NSW was also assessed based on modified IUCN Red-List criteria where suitable monitoring data was available (IUCN 2001; IUCN 2008). However, there is no widely accepted method for assessing the sustainability of ecological communities.

Again, limited data of a suitable nature is available for assessing the sustainability of threatened species. Of the species that could be assessed, the majority (94% of threatened fauna and 82% of threatened plants) have a moderate or greater risk of extinction, mainly due to ongoing contractions in range, as described previously for birds, or to severely restricted distributions. The prospects for the long-term sustainability of most NSW threatened species are generally poor.

Pressures

The decline in vertebrate species is largely due to the pressures that arise from meeting human needs including food production, urban expansion and consumption of natural resources. The loss and degradation of habitat has been compounded by the introduction of pests and weeds, diseases, the impacts of altered fire regimes and pollution that alone, or in combination, affect individual species and ecosystems.

The major pressures on species diversity in NSW include:

• clearing, fragmentation and disturbance of native vegetation (Biodiversity 7.1)
• land degradation (Land 5.1)
• the introduction of invasive species (particularly foxes and cats) and weeds (Biodiversity 7.4)
• overgrazing by cattle, sheep and invasive herbivores (Biodiversity 7.1)
• changes to fire regimes (Biodiversity 7.5)
• changes to water flows (Water 6.1)
• the introduction of exotic diseases
• overfishing and fishing bycatch (Biodiversity 7.6)
• climate change (Climate Change 2.3).

Overall, the processes that have an impact on threatened species are the same as those threatening biodiversity more generally.

Listed key threatening processes

The TSC Act and FM Act both list processes that threaten the sustainability of native plants and animals, especially threatened species. At present there are 33 key threatening processes (KTPs) listed in the schedules of the TSC Act and seven KTPs listed in the schedules of the FM Act. Four KTPs have been added to the schedules since 2006.

Table 7.4 provides a summary of the KTPs listed under the TSC Act, grouped by the type of processes or threats they describe. Out of 33 KTPs listed, pest and weed invasions are the subject of 18 (55%). Clearing of native vegetation is dealt with under a single KTP. A further seven KTPs involve various forms of habitat modification. KTPs in NSW were reviewed recently (Auld & Keith 2009).

Table 7.4: Summary of the key threatening processes listed in NSW

Source: DECC and DPI data 2008

Clearing and disturbance of native vegetation is the threat affecting the greatest number of threatened species (87%), followed by the introduction of invasive species (70%) (Coutts-Smith & Downey 2006). However, introduced pests (particularly predators) are believed to have caused a greater number of extinctions than any other type of threat (Dickman 1996a; Dickman 1996b). The clearing of native vegetation and impacts of introduced species remain the two most significant threats to biodiversity in NSW.

Climate change

The distributions of most species and ecological communities are largely determined by biogeographical factors, including a range of climate variables. Climate change is likely to exacerbate the impacts of other threats on flora and fauna, as species already under pressure will have lowered resilience to cope with the impacts of climate change. Climate change is likely to have the greatest impact on species with restricted distributions and limited ability to shift their range (DECCW in prep.). There is already some evidence that climate change is beginning to have an impact on biodiversity in NSW (Climate Change 2.3).

Responses

Legislative and policy frameworks

Under priority E4 of State Plan 2006: A new direction for NSW (NSW Government 2006) the targets are:

• Target 2: 'By 2015 there is an increase in the number of sustainable populations of a range of native fauna species'
• Target 3: 'By 2015 there is an increase in the recovery of threatened species, populations and ecological communities'.

A review of State Plan 2006 commenced in August 2009 and this may adjust some of the plan's priorities and targets.

Legislation

The main legislation affecting conservation of species in NSW is the TSC Act, which provides a number of mechanisms for protecting threatened species, populations, communities and their habitats, and the FM Act, which provides similar protection for threatened fish, marine invertebrates and marine vegetation.

Recent legislative reforms have seen the introduction of two new listing categories for critically endangered species and vulnerable ecological communities (Table 7.3).

Strategic policy framework

Since SoE 2003 there has been a fundamental shift in focus from the recovery of individual threatened species, an approach which is largely reactive, to a more strategic focus on conservation at the landscape level and the protection of communities and habitats. Consistent with this new approach, there is now a greater emphasis on addressing the threats to biodiversity and the processes and drivers of biodiversity decline more generally. The objective is to maximise the benefits for all species and not just those that have been listed as threatened.

A range of strategies is available to address the decline in biodiversity and enhance conservation and recovery. These will be described in a revised NSW Biodiversity Strategy which is under review, and include:

• securing protection of habitat in perpetuity in the terrestrial reserves and marine parks systems, supplemented by a range of conservation mechanisms on private land (Biodiversity 7.3)
• stopping or reducing broadscale clearing of native vegetation through regulation, approvals and compliance systems (Biodiversity 7.1)
• restoring or rehabilitating vegetation and habitat and improving land management, delivered mainly through a variety of property vegetation plans (PVPs) (Biodiversity 7.1)
• improving landscape connectivity through revegetation, and establishing corridors and linkages between parks and reserves, including the Great Eastern Ranges Initiative (Biodiversity 7.1; Biodiversity 7.3)
• identifying species, populations and communities that are under threat and the KTPs that cause them to be threatened
• reducing the threats to biodiversity through priorities action statements and threat abatement plans.

Threat abatement plans

Threat abatement plans (TAPs) are developed to manage listed KTPs and aim to:

• outline actions to manage the threatening process
• explain how the success of these actions will be measured
• identify the authorities that will be responsible for carrying out those actions
• provide a cost estimate and timetable for carrying out the plan.

There are 10 TAPs in operation in NSW and several more in preparation. At present most TAPs target threats from invasive species and disease.

The Predation by the Red Fox TAP was the first to be completed under the TSC Act (NPWS 2001) and was recently updated. The plan implements fundamental changes to strategies for fox control, in order to enhance the conservation of native fauna. In particular, the plan identifies priorities for fox control and sets out a framework for collaborative programs of control across all tenures. It also describes best-practice guidelines for fox control and provides for monitoring programs which measure the response of threatened species to fox control.

Priorities action statements

The NSW Government has implemented reforms to streamline the delivery of recovery actions for threatened species, populations and ecological communities. Priorities action statements (PASs) provide a strategic approach to the recovery of threatened species and threat abatement planning by listing and prioritising all conservation actions. There is one PAS for entities listed under the TSC Act and another for entities listed under the FM Act.

The PAS for the TSC Act, which mainly applies to terrestrial species, identifies 34 broad strategies for recovery of threatened species and abatement of KTPs. These are summarised under 11 types in Table 7.5. Each of the strategies has more specific actions listed under them. The PAS prioritises conservation actions in terms of the importance of the action, the likelihood of success and the ease of implementation.

Table 7.5: Conservation actions by category assigned to threatened species and ecological communities by the TSC Act priorities action statement

Source: DECC data 2008

Notes: Data applies only to listings under the TSC Act.
No data is available on the number of actions completed.

The number of actions which concern monitoring (768) is particularly high and reflects the NSW Government's efforts to address data deficiencies that are evident in the knowledge of species and their sustainability.

BioBanking

The Biodiversity Banking and Offsets Scheme (BioBanking), which commenced in August 2008, is a market-based scheme designed to reduce the impacts of development on biodiversity, particularly threatened species and ecological communities.

BioBanking provides the opportunity for developers to offset development impacts on biodiversity at a site by improving its management at other sites, provided that overall biodiversity values are improved or maintained. Offset (biobank) sites must have the same threatened species or ecological communities as those affected by the development, and sites must be managed for conservation in perpetuity.

At the same time, BioBanking provides an opportunity for rural landowners (offset providers or private conservation stewards) to generate income by managing land for conservation. Biodiversity credits can be generated by committing to enhance and protect biodiversity through a biobanking agreement and these credits can be sold, generating funds for the management of the site.

Land Alive gives Aboriginal landowners a chance to create jobs and business opportunities by managing land for conservation through BioBanking. Aboriginal landowners can generate income while enhancing their role as land stewards with their unique knowledge of Aboriginal culture.

Planning and biocertification

Recent changes to legislation provide for mechanisms to better integrate planning needs with biodiversity conservation objectives on a strategic basis at the regional level. Regional strategies balance social, economic and environmental objectives in setting out a blueprint for future development (see People and the Environment 1.2).

Regional conservation plans, such as for the Lower Hunter, will complement the regional strategies by assessing the likely impacts of future development in establishing a practical framework to improve or maintain biodiversity at the landscape level. Regional conservation plans (one has been finalised to date) will identify conservation priorities, including additional reserves and important corridors, and guide the process of providing biodiversity certification (biocertification) of environmental planning instruments (EPIs), such as local environmental plans. It also provides direction for investment in biodiversity through market-based instruments, such as BioBanking, and for other sources, such as catchment management authorities.

Biocertification of EPIs is a new mechanism for conserving biodiversity and protecting threatened entities listed under the TSC Act. Certification enables the streamlining of development assessments and approvals by a planning authority. Once an EPI is certified, site-by-site assessment of threatened species is not required for any subsequent developments within the area covered by the EPI.

On-ground programs and management

The protection of native species and reduction of threatening processes is directed by the framework described above and delivered through the following programs.

Reservation

A dedicated system of parks and reserves is the cornerstone of conservation efforts to preserve and protect biodiversity and ecosystems in NSW. Approximately 8.4% of land and 34% of marine waters has been incorporated into the reserve system. Conservation in reserves is supplemented by a range of conservation measures for other public and private lands (Biodiversity 7.3).

Protected areas provide refuge for a significant proportion of threatened species, and approximately 85% of all vertebrate groups are represented within the reserve system (DEC 2005). The large number of PAS actions relating to community engagement for conservation activities on private land (355 in total) reflects the increasing commitment to, and support for, conservation on private land.

Regulation of clearing

The clearing of native vegetation and harvesting of non-plantation native forest timber on rural lands are regulated under the Native Vegetation Act 2003, and enhanced systems for enforcement and monitoring compliance are now in place. Approvals for clearing of native vegetation have fallen significantly and clearing of woody vegetation has remained stable for a number of years. At the same time, measures to promote revegetation and improve the condition and management of native vegetation have been implemented through PVPs. Provision is made for important corridors and buffers in urban planning processes (Biodiversity 7.1).

Management and control of invasive species

Eradication of invasive species is seldom feasible. However, control of high priority invasive species, such as foxes and bitou bush, is targeted at areas of high conservation value and is being delivered through TAPs. Broadscale rabbit control is being delivered through the release of myxomatosis and rabbit haemorrhagic disease, while rats, mice and rabbits have been eradicated from several NSW islands. However, the intensive control that is necessary to improve the condition of flora and fauna is largely limited to some conservation reserves (Biodiversity 7.4).

Management of native species

The NSW Government oversees a Kangaroo Management Program that monitors numbers of the four large kangaroo species to ensure that populations do not expand at the expense of other native fauna.

Recovery plans for threatened species

Recovery plans have been used to guide on-ground management and have resulted in positive outcomes for a number of threatened species. These programs require ongoing funding, in some cases for many years, to maintain the positive outcomes.

Adaptation to climate change

The NSW Government's response to climate change impacts on biodiversity includes the NSW Biodiversity and Climate Change Adaptation Framework (NSW Government 2007) and the Adaptation Strategy for Climate Change Impacts on Biodiversity (DECC 2007). The adaptation strategy aims to reduce the impacts of climate change by building the reserve system and protecting high quality vegetation remnants, improving connectivity across the landscape to allow for the movement of species, restoring habitat in highly fragmented ecosystems to improve resilience, and taking action to protect individual priority species.

A Statement of Intent for Anthropogenic Climate Change, which is currently being prepared in response to the listing of anthropogenic climate change as a KTP, will propose actions to deal with the impacts of climate change on biodiversity in NSW (Climate Change 2.3).

Other threats

The use of water from rivers, wetlands and groundwater sources has also been regulated, with some allocations now being made for environmental flows (Water 6.1; Water 6.2). Management of fire has focused largely on reducing risks to people. However, research on the relationships between fire and the population dynamics of a range of Australian flora and fauna is now allowing optimal fire regimes to be developed to maintain biodiversity and to be considered in fire management (Biodiversity 7.5).

Future directions

New reforms and mechanisms to enhance the conservation of biodiversity have been introduced since 2003, and this process is ongoing. Reviews of legislation and of the effectiveness of investments to conserve threatened species using the PAS are planned for 2010. Consideration will be given to the optimal targeting of resources across the landscape so that large-scale threats are managed through tools such as regional planning.

In many cases it is still too early to assess the effectiveness of these new measures in addressing issues that are pervasive and long-standing. Significant trends and changes in the status of species often become clear only over longer time frames, and it will require sustained commitment to conservation objectives and perseverance to achieve lasting gains and the sustainability of many native species.

The strategic approach to conservation at the landscape level will continue. By addressing the main threats to biodiversity and the drivers of biodiversity decline, outcomes and benefits will be maximised for all species. However, species-specific recovery actions may still be developed in cases where specific habitat requirements are identified or where the only populations remaining are in highly disturbed habitats.

Regional programs that deliver on-ground actions to address strategic conservation objectives or diminish the impacts of threatening processes are likely to achieve the most effective outcomes in maintaining the diversity of native species.

Climate change is expected to place further stress on already fragmented ecosystems and will lead to shifts in the distribution of native species, resulting in both losses and gains at the regional level. Measures to improve connectivity across landscapes and build the health and resilience of natural systems will enhance the capacity of species and ecosystems to cope with disturbance and adapt to changes in climate.

The information that presently supports the listing of threatened species is not collected systematically and this may lead to imbalances in the listings. The provisions of the Monitoring, Evaluation and Reporting Strategy should allow for monitoring that is more representative and targets specific information gaps. This will provide a more effective basis for establishing the status of species in the future and ensure that those species in real need of protection are identified.

Greater research effort will provide a better understanding of conservation and species dynamics, and their interaction with threatening processes and disturbances. This will assist in optimising conservation outcomes within different land uses and across the whole landscape.

More information is also needed about the factors contributing to the resilience or success of some native species and processes, such as expansions in range or increases in population, in contrast to the contractions or declines of many other native species. Such processes are less commonly studied than threats but are likely to significantly influence future outcomes for biodiversity, and should be considered against a broader perspective of the global homogenisation of biodiversity through the mass movement of species.