Ecological Communities: A way forward

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Ecological Communities: A Way Forward
Threatened Species Scientific Committee
Advice for
The Minister for Environment and Heritage, September 2004
Summary
Since July 2000 the Committee has been striving to implement the provisions of the Environment
Protection and Biodiversity Conservation Act 1999 (EPBC Act) relating to ecological
communities. Problems of particular concern to the Committee have been those associated with
defining an “ecological community”. This is complicated by the view of some stakeholders that
listing of ecological communities addresses the wider issue of “land clearance regulation”.
The Committee has previously established working guidelines for the definition of ecological
communities. This followed from a series of workshops with scientists and other stakeholders.
However, nominations for listing of threatened ecological communities continue to be extremely
difficult to assess. The fundamental problems are: (1) the definition and circumscription of what
constitutes an ecological community; (2) the extent to which different levels of condition
(degradation) take the community away from its defined identity; (3) whether defined
communities can be, and/or need to be, mapped; (4) the scale at which communities can be most
sensibly defined; and (5) the absence of a more strategic approach for evaluation and listing of
communities (currently, many are nominated in an ad-hoc way that is divorced from any more
systematic or broadly strategic context). Many of these issues are so grey and indistinct that they
challenge the judgement of the Committee, and hence are likely to lead to substantial confusion
amongst the public generally and hence distrust about the workings of the EPBC Act. This paper
seeks to improve the clarity and workability of these definitional issues, and to identify improved
methods for assessing ecological communities.
Ecological communities are inherently complex in an undisturbed state. This is especially so in
Australia where the age of the landscape and the variability of its soils frequently leads to
transitions that occur on scales of less than 100 meters and most often occur at scales that are only
a few orders of magnitude greater. The accompanying spatial change in environments can be
more gradual, subtle and complex than is the case in most other continents (where marked
topographic variation and steep climatic gradients dictate sharp environmental disjunctions).
The result is Australia’s naturally variable landscapes where ecological communities undergo a
transition (see the Glossary at Appendix 1) from one state to another and from one ecological
community to another with no clear demarcation between them. These problems are compounded
when ecological communities occur in fragmented landscapes where natural resource management
(NRM) and land use change become significant ecological drivers that distort, in often
idiosyncratic ways, the underlying natural variation. These influences lead to various states or
expressions of an ecological community occurring in different conditions from the pristine to the
locally extinct.
The Committee has used workshops in the past to resolve difficult issues and chose to do so again
in this case. A workshop of national experts was convened and provided with background papers
that spelt out the challenges that had been identified by the Committee. A particularly difficult
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ecological community, Yellow Box - Red Gum Grassy Woodland, was chosen as a case study to
focus discussions of the workshop.
The Committee considered the report of the workshop in July and September 2004 and this advice
is the final synthesis of this process.
The recommendations of the Committee regarding Ecological Communities are:
Defining and listing of ecological communities
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Any approach taken to define and list threatened ecological communities must be at the
national extent, scientifically credible, objective and repeatable, practical, easily understood by
the general community and applicable in the NRM framework.
“Broad-extent” communities should be listed where they can be clearly defined.
In the intensive land use zone (i.e. areas where development has “matured”) better outcomes
will be achieved by breaking a broad-extent ecological community into smaller units that
allow mapping consistent with current regional NRM mapping activity. The most prospective
approach would be to use the existing regions mapped under the Interim Biogeographic
Regionalisation for Australia (IBRA). This approach would make description of the ecological
community more accurate, thereby making it easier for the general public to identify the
ecological community on the ground (for example an ecological community would be
described as ABC grassy woodlands of the X X IBRA Region(s)).
When providing advice on a listing, the Committee would establish if the ecological
community in question occurs naturally in different states and, if so, establish condition
classes for each natural state. These condition classes would reflect stages in gradients of
degradation and disturbance.
Where different condition classes can be assessed objectively, the combination of listing and
conservation advice by the Committee would allow for the better condition classes to be
protected by listing. Guidelines provided by the Department would give clear advice on how
to recognise the protected community (including different natural states of the ecological
community) and how decisions on referrals would be made. The management of unlisted
lower condition class expressions of the ecological community would be through established
NRM processes.
Addressing the status of areas of intergradation between ecological communities may be more
complex because some areas within the intergrading zone could belong to two ecological
communities simultaneously. This situation should be addressed in listing advice by
identifying indicator(s) that define the “administrative boundary” of each of the ecological
communities in question. In effect this would put the status of the ecological community state
in question into one or other of the ecological communities for management purposes.
The Committee’s conservation advice when recommending listing could include how to deal
with ecological communities of large extent where, with experience, it may be necessary to
adjust administrative guidelines.
Strategic regional assessments should be undertaken to identify ecological communities that
are a high priority for listing, rather than have an ad-hoc approach driven solely by public
nominations.
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Where public nominations are received, they should where possible be integrated with the
strategic approach. The co-operation of nominators should be sought to assist in this
approach.
The conservation advice of the Committee at listing recommendation and preparation of
administrative guidelines by DEH will assist in improving community consultation and
communication associated with the listing of ecological communities. The integration of
listing with the NRM process will require cooperation with the Department of Agriculture,
Fisheries and Forestry, the States and Territories and regional bodies. The Committee
recommends that the actual legal mechanism used to achieve these outcomes be explored
by the Department of Environment and Heritage.
Some issues related to nominations and conservation of threatened ecological communities
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Throughout most of the area of Australia where fragmented woodlands and grasslands occur
Travelling Stock Routes and Reserves (TSRs) provide linear expressions of significant native
vegetation. In many places they are the dominant form of connectivity in the landscape.
TSRs are under threat from changes in their management due to financial and other pressures
being placed on management agencies. This could lead to their sale or these critical remnants
being subject to intensive use regimes. The flow-on effect of this is degradation of ecological
communities on TSRs. The Committee believes that the Commonwealth could make a
positive intervention on this matter that would achieve rural community and conservation
benefits.
The Committee believes that that while ecological communities are administratively and
scientifically difficult, the use of ecological community nomination as a tool to address land
clearance continues to aggravate the situation
Coordination
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The Committee further reaffirms its commitment to a multi species multi-community
approach to NRM planning.
Building public support and understanding
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The Committee believes that public support for the listing of ecological communities and
management processes would be enhanced if the complexity of the issues was better
understood, and there was greater recognition of the means to resolution of such complexity in
definition and management. The Committee recommends that the Minister consider:
1. The release of this advice to interested parties.
2. The development of a summary of this advice for general release as a pamphlet.
3. Publicising the Commonwealth’s timetable for strategic assessments of ecological
communities.
4. The preparation and submission by the Committee of a note to an Australian journal so as
to better inform the community of ecological scientists of the approach that has been
adopted.
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Ecological Communities: a way forward:
Introduction
Background
Since July 2000, the Committee has been striving to implement the provisions of the Environment
Protection and Biodiversity Conservation Act 1999 (EPBC Act) relating to ecological
communities. Problems of particular concern to the Committee have been those associated with
defining an “ecological community” in practical terms within the landscape. This is complicated
by the view of some stakeholders that the listing of ecological communities is a solution to the
“land clearance problem”.
The Committee has previously established guidelines for the definition of ecological communities.
This followed from a series of workshops with scientists and other stakeholders. However,
nominations for listing of threatened ecological communities continue to be extremely difficult to
assess. The fundamental problems are: (1) the definition and circumscription of what constitutes
an ecological community; (2) the extent to which different levels of condition (degradation) take
the community away from its defined identity; (3) whether defined communities can be, and/or
need to be, mapped; (4) the scale at which communities can be most sensibly defined; and (5) the
most strategic approach towards evaluation and listing of communities (currently, many are
nominated in an ad-hoc way that is divorced from any more systematic or broadly strategic
context). Many of these issues are so grey and indistinct that they challenge the judgement of the
Committee, and hence are likely to lead to substantial confusion amongst the public generally and
hence distrust about the workings of the EPBC Act. This paper seeks to improve the clarity and
workability of these definitional issues, and to identify improved methods for assessing ecological
communities.
Part of the Committee’s response to these dilemmas has been to initiate a strategic approach to the
assessment of ecological communities. Priorities were set for each National Vegetation
Information System (NVIS) group and systematic work was begun. When nominations were
received, these were considered in this context and, in some cases, if they did not fit the
framework, they have been recommended for rejection pending a more systematic assessment. In
other cases (for example brigalow) recommendations for rejection were accompanied by a more
systematic listing that incorporated the ecological communities that were individually nominated.
This approach has been challenged as legally suspect by the NSW Environmental Defenders
Office, but no legal action has been taken. Pressure has, however, been brought to bear on the
Government for more rapid progress of the listing of ecological communities.
The Committee considered the land clearance issue in 2001 and recommendation on a Key
Threatening Process (KTP) was made to the Minister at the time. He accepted the
recommendation and listed. The Committee has revisited the issue several times and believes that
it should be separated from the issue of ecological communities. The separation has been
maintained in this paper, but a recommendation is made that reflects previous deliberations of the
Committee.
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Science and the use of workshops
The Committee, when advising the Minister, is always conscious of the need to focus on good
science, defendable scientific judgement and conservation outcomes. The list of threatened
ecological communities is one tool designed to support the governments’ and community’s desire
to conserve and protect natural systems.
To widen the input and improve the scientific content of its work, the Committee has used
workshops of national experts to resolve difficult issues. It chose to do so in the case of ecological
communities.
An expert workshop was initiated by the Committee to explore technical and scientific issues that
have arisen regarding ecological communities over the past four years.
The workshop was confined to examining the challenge that relates to terrestrial ecological
communities. Issues in relation to aquatic and marine ecological communities are
important issues to be addressed in the future.
Committee synthesis of workshop report and Committee deliberations
Overall view
The Committee endorses the agreement amongst national experts attending the workshop that the
challenges surrounding the conservation of ecological communities can be resolved, provided that
listings are scientifically credible, easily understood by the community, and capable of being used
in an effective NRM regime. The Committee also recognises that nominations of ecological
communities can be motivated by the desire to protect ecological communities and to regulate
land clearance. As noted above, this confusion of purpose is part of the problem. These two
objectives should be addressed separately.
Definition and Description of Listed Ecological Communities
Ecological communities may occur in a range of states (1 to n, depending on the ecological
community). Within these states there exist a number of condition classes. A practical
conservation definition of an ecological community would identify “high quality” elements of the
state(s) of the ecological community that should be protected by the EPBC Act and “significantly
modified” elements that may attract appropriate NRM interventions. This approach would allow
landholders to access funding available through their regions to assist in management of properties
to achieve better outcomes for ecological communities and affected landholders.
Australia’s ecological communities can be represented diagrammatically as shown in Figure 1.
The figure illustrates the complexity of the ecological community issue and reflects the way in
which the Committee has approached previous recommendations to the Minister. The level of
ordination that is used to determine the ecological community is the key point.
EC1 communities (Figure 1) are ecological communities that are recognisable isolated types that
are determined by either deep history1, geomorphology, geology or all three. Such ecological
communities may not have declined in extent, but are under
“Deep History”: History beyond our ability to measure. All Australian ecological communities have for the
last 60,000 years been subject to two ice ages and human influences. Consequently we can often only speculate
about the historic factor in the expression of a current ecological community.
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significant threat or may have become extinct in some areas. Mound springs are a currently
a listed ecological community under the EPBC Act that would conform to EC1 in Figure 1.
These ecological communities can be either existing or destroyed2 and the listing advice
reflected these conditions. An additional complication is that such ecological communities
vary in species composition as a result of their long history of individual isolation. This
required a special phrase to describe the ecological community for listing as “The
community of native species dependent on natural discharge of groundwater from the Great
Artesian Basin”.
Closed forest ecological communities with significant species variation, but consistent structural
and dominant elements (for example vine thickets and rainforest) either exist or are cleared with
easily recognised residuals dotted across the landscape. These are EC2 in Figure 1. If a high level
of ordination is applied to these ecological communities, they can be described structurally or in
terms of a few signature species.
Figure 1. A framework for understanding ecological communities; ecological communities may exist in
one or more types each of which can have one or more states. These state(s) exist in a number of
condition classes that reflect a range of integrity.
EC3 in Figures 1 and 2 represent the fragmented woodlands and grasslands that typically occur in
a band west of the Great Dividing Range and in an arc into South Australia. These communities
naturally intergrade, occur in mosaics that were, probably, manipulated by traditional Aboriginal
management and are now fragmented.
Some EC3 ecological communities have different naturally occurring states. This is recognised
ecologically in terms of a system of states and transitions between these states. The totality of
these states makes up the broad extent of the ecological community.
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The most dramatic cause of this is the loss of water flow because of a decline in Great Artesian Basin pressure.
Other causes are the use of the springs as unfenced and reticulated watering points
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Where two closely related ecological communities exist, it is possible that some forms can be part
of either ecological community. Additionally, depending on natural and human influences, a state
could be changed (through active management or continuing threat) into a condition that is
entirely within one ecological community. This is represented in Figure 2. The Committee
believes that ecological community definitions for such complex natural systems need to
recognise the on-ground reality.
A functional definition of an ecological community could incorporate:
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recognition that some ecological communities can exist in a number of states;
recognition of the degree of disruption that the system has undergone;
the possibility of restoration; and
areas where the ecological community is effectively intact.
EC4 represents naturally determined and intact ecological communities and ecological
community complexes. These occur in the extensive areas of inland Australia and in
forested areas around the seaboard. Examples include much of the mulga lands,
extensive forested areas subject to the Regional Forest Agreements, connected National
Parks along the Great Dividing Range and some World Heritage Areas.
Figure 2. A model for understanding ecological communities (EC3 in Figure 1) that may contain sub-types
(perhaps at an IBRA regional level); each sub-type may include a range of states. Each state may include
condition classes (1 to n), some of which might be so degraded as to warrant exclusion from the ecological
community listed under the EPBC Act.
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Figure 3. Representation of possible relationships between differing forms of an ecological community. States of
ecological communities are indicated by circles and transitions by arrows. Transitions may be uni or bi
directional depending on a range of biophysical and at times anthropogenic variables.
States and Conditions
The issue of state is an important consideration within this framework. If a range of states is
identified as constituting the ecological community, states need to be clearly expressed and be
capable of being recognised in the field. Indicators of each state and of the overall ecological
community should be defined to allow unambiguous recognition of the ecological community.
For each state, “condition classes” could be measured as points along a continuum from the intact
ecological community state to a situation in which the ecological community in a particular state is
locally extinct. Measurement points could include the structure of the particular state of the
ecological community, its species composition, or the presence or absence of agreed indicator
species or ecological properties. For an ecological community that does not have a number of
states, the same principles with respect to condition apply.
In the case of the woodland ecological communities, several broad types exist. For listing
purposes, the ecological communities could be described as having a “recognisable name” as it
occurs in one or more IBRA regions (i.e. AA ecological community of ABC IBRA Region(s)).
Each such ecological community would have one or more recognisable states.
For each recognised woodland ecological community, its states could be:
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An ecological community state in which all the components of over storey and understorey
are present.
 An ecological community state that has an understorey of significant value botanically.
 An ecological community state that has an over storey with the presence of the recognised
ecological community’s dominant and co-dominant species.
Threshold variables for establishing the “condition classes” of each of these states may, but not
exclusively, include:
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patch size;
connectivity;
native plant species presence and abundance;
native plant species diversity;
over storey projected foliage cover;
understorey composition and cover; and
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recognised faunal values.
These variables could be assessed against identified and locatable condition examples. These
examples would change from state to state for each “recognised ecological community”. Within
each “recognised ecological community” some of the condition classes would be identified as
being part of the listed ecological community and others may be considered too degraded to
warrant listing. The latter would be identified for rehabilitation and management through the
NRM and recovery planning process. Figure 4 illustrates this approach. This process would
created the “administrative boundary” of the ecological community in question and the logic for
this should be explicit in listing advice and conservation advice to the Minister.
Figure 4. The continuum of an ecological community states’ condition. Communities usually move to
“lower” condition under pressure and potentially to “higher” condition if pressure is relaxed or
management interventions are made. The exception is systems that are beyond recovery because of total
species loss or a loss of significant geomorphologic elements. In such a case, full recovery is impossible,
but “functional” recovery should be an NRM objective.
Practical considerations: (a) Applying these principles
The Committee recognises that even within this framework not all expressions of a listed
ecological community are equal. A judgement would need to be made about the value of each for
effective NRM conservation management and protection. The Committee believes that only high
quality examples of a listed ecological community should trigger the assessment provisions of the
EPBC Act. Lower quality, but ‘recoverable’, examples should be identified for management
through the NRM and recovery planning processes. Proceeding in this way creates scope for some
recovery of the listed community without taking away the focus from those areas that warrant
protection. While other degraded areas would not be addressed within the context of the EPBC
Act, they still retain conservation value and are best addressed by State and regional NRM
processes. The Committee recommends that the actual legal mechanism used to achieve these
outcomes be explored by the Department of Environment and Heritage.
This approach is consistent with the definition of an ecological community, within the EPBC Act,
as:
“an assemblage of native species that: (a) inhabits a particular area in nature;
and (b) meets the additional criteria specified in the regulations (if any) made for
the purposes of this definition”.
This approach is also consistent with the Committee’s advice to the Minister of July 2000 that sets
out a model for dealing with the modified landscapes of Australia.
Practical considerations (b) Necessary splitting and lumping
The effect of this approach would be that apparently intact or nearly intact expressions of the
ecological community would be listed as endangered or critically endangered. In applying this
approach, it is possible that for a widely distributed community complex, different expressions
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of the ecological community (called subtypes above) will be considered for listing as separate
entities (recognised ecological communities). This process would be greatly assisted if
benchmark sites for each expression or state of the ecological community were identified when
recommending listing and these were then used to identify other sites. This would provide an
iterative process that would assist in the progressive development of accurate locational records
of the listed entity. The approach builds on linkages with existing mapping processes in some
States. It would appear this is particularly true for Queensland with its well-advanced regional
vegetation management planning that is already in place. In addition, for closely related
ecological communities, the break point between ecological communities needs to be explicitly
established at listing. This could be an IBRA boundary or a structural or compositional
characteristic of each ecological community.
Practical considerations; (c) Land clearance
The Committee believes that that while ecological communities are administratively and
scientifically problematic, the conservation problem driving their decline is simpler. In reality in
most of the intensive land use zone of Australia, the limits of land clearance have been exceeded.
Consequently landscape function is significantly compromised. The solution is to regulate3 land
clearance, create incentives for those who manage intact native vegetation and implement
necessary landscape management and restoration. The Committee believes that the land clearance
key threatening process listing opened the way for the Commonwealth to develop such a land
clearance threat abatement plan. The Committee accepted advice at the time of recommendation
to the Minister that a threat abatement plan was not needed. The Committee now believes that a
national position on land clearance, that is simple and informs policy, is needed. The Committee
accepts that this should not be confused with the ecological community’s issues but it nonetheless
is parallel with it.
A practical model
Figure 5 shows the logical sequence by which the process set out above can be applied.
Special cases
A special case might be made for situations where there are no, or extremely few, intact
expressions of an ecological community, but where the possibility of restoration exists. In such
cases, the value of an area is determined by its potential rather than its actual condition.
Special complexity
In the south-west of Western Australia, and possibly elsewhere, conventional expressions of
ecological communities do not always occur. Often an ecological community is only recognisable
as a large number of endemic species and associations intermixed to form complex and highly
diverse patterns that do not easily conform to conventional descriptions. In these cases, the extent
of the ecological community is best described by using geomorphic features. This represents a
workable solution for some Western Australian ecological communities. Similar practical
approaches may be needed for other ecological communities that do not readily conform to
conventional descriptions. A precedent for this treatment has already been set in the descriptions
used for the listed ecological community
“Community of native species dependent on natural discharge of groundwater from the Great
Artesian Basin”.
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In most areas this will be a cessation of land clearance but exceptions may occur.
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Travelling Stock Routes and Reserves
The importance of travelling stock routes and reserves (TSRs) for ecological communities within
highly fragmented landscapes was highlighted at the workshop and endorsed by the Committee. In
most of the area of Australia where fragmented woodlands and grasslands occur, Travelling Stock
Routes and Reserves (TSRs) provide linear expressions of significant native vegetation. In many
places they are the dominant form of connectivity in the landscape. Concern was expressed about
the threats to the integrity of the ecological communities present on TSRs arising from the
changing patterns of stock movement, the income patterns for management agencies, the possible
sale of TSR’s and general changes in rural Australia. A suggestion was made that the
Commonwealth should consider listing “the loss of integrity of travelling stock routes and
reserves” as a key threatening process, so that a threat abatement plan could be made to find
practical ways to address the problem. In the development of any such plan, a critical factor
would be the willing involvement of local groups charged with the management of stock routes
and reserves.
Communications
A recurring theme in the discussion during the workshop and between the Committee and
interested stakeholders has been the necessity to continuously improve public information and
communications with stakeholders about ecological communities. Better communication is
required between:
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Commonwealth and State bodies that make listings;
Listing authorities and NRM management agencies;
NRM management agencies and program management groups; and
Government agencies in general and rural landholders.
The Committee was pleased that representatives of all these groups did work positively together at
the workshop that has contributed to this advice.
The Committee endorses the development of a tool kit that could be used by the Committee / DEH
partnership. This tool kit would consist of four elements, namely:
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A decision algorithm that includes the substance of this report.
A conservation action checklist that focuses on the downstream implications of the
recommendation.
A planning system for the regions that facilitates interaction between DEH, State agencies
and regional NRM groups.
A communications strategy to better inform and build public support for ecological
communities.
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Figure 5. Algorithm for guiding the decision making process for listing ecological communities.
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Appendix 1
Glossary
State
The state of an ecological community describes a recognizable form of that ecological community.
For example three recognizable states of the Grassy Box Gum Woodlands may be: a state which
contains both an overstorey and an understorey; one that contains just an overstorey because the
understorey has been removed through processes such as grazing; and, one that contains just an
understorey because the overstorey has been removed.
Condition Class
The condition of a particular area of vegetation describes how far the vegetation has changed from
the pristine, or ideal, ecological community that existed prior to European settlement. An area that
is in good condition resembles this ideal more closely than an area in poor condition. A condition
class describes a range of conditions that are thought to be of similar value.
Expression
An expression of an ecological community is any definable unit of that ecological community. For
example it can be the good condition class of the overstorey state of the Grassy Box Gum
Woodlands. Thus in this case the expression is described by both the state and condition.
Sub-type
Ecological Communities may have sub-types represented by a slightly different floral
composition. These differences are a result of the latitudinal and longitudinal gradients along the
extent of the ecological community. Soils, topography and geology can also influence the make-up
of the ecological community in particular areas. As the Interim Biogeographic Regionalisation of
Australia largely reflects these differences, it is a good example of a regional system that could be
used to define subtypes of ecological communities.
Transition
Transition is the movement of specific area of an ecological community from one state to another
state. This movement may be due to human activities such as tree clearing, which can change an
area from a state containing both an overstorey and an understorey to a state that contains only
understorey.
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