Draft Description of an Ecological Community
Nominated for Listed under the EPBC Act
Lowland Seasonal Wetlands of South-eastern Australia
Photo: Matt White DSEWPaC
Nominations for both “Temperate Lowland Plains Grassy Wetland” and the “Victorian
Volcanic Plain Freshwater Swamps” were received by the Department of Sustainability,
Environment, Water, Population and Communities. Since both nominations related to wetlands
that were similar in their description and overlapped in their distribution, both nominations
were placed on the 2008 Finalised Priority Assessment List (FPAL) to be jointly assessed for
listing as a threatened ecological community.
A number of scientists and land managers with expertise of the nominated wetlands in southern
Australia were contacted and a technical workshop was held to assist with defining the
ecological community for assessment. The technical workshop for these nominated wetlands
was held on 11 – 12 October 2010 in Colac, Victoria.
Technical workshops are used to obtain and discuss expert opinion on the nature and extent of
a nominated ecological community. They are an important step in the nomination assessment
process. However, additional work is required before the Threatened Species Scientific
Committee is in a position to provide the Minister with scientific advice on whether or not a
nominated ecological community qualifies for listing under the Environment Protection and
Biodiversity Conservation Act 1999 (EPBC Act).
The next steps include further discussion with experts (both those who attended the workshop
and others who did not), examination of the available scientific literature, and evaluation of
datasets relevant to the ecological community. There is also a statutory requirement to
undertake public consultation. The nomination(s) and the workshop report, as agreed for
release by the Threatened Species Scientific Committee, will be made available for comment
through the department‟s website. A wide variety of stakeholders (e.g. state agencies, local
councils, landcare and conservation groups, rural/farmer groups) will be directly contacted to
seek comments and to encourage comment from others through their networks.
More information about the nomination and assessment process can be obtained at:
This report summarises the outcomes from the technical workshop covering both the
nominated wetlands. Additional information has been added to this report as a result of further
discussions and information. The format of this report closely follows that of the listing advice
to provide a better approximation of the final listing advice. However, it is important to note
that this workshop report was compiled by the Department of Sustainability, Environment,
Water, Population & Communities and reflects one input to the complex nomination
assessment process. Release of this report does not imply endorsement of all of its contents by
the Department, members of the Threatened Species Scientific Committee, workshop
participants or other experts.
The Department welcomes views from experts, stakeholders and the wider community on the
nomination and this report to further inform its nomination assessment process. To assist in
this matter, a series of specific questions have been identified to target responses on
particular issues as well as the report in general.
1. Name of the ecological community
Lowland Seasonal Wetlands of South-eastern Australia
Two public nominations were received to list the “Temperate Lowland Plains Grassy Wetland”
and the “Victorian Volcanic Plains Freshwater Swamp” ecological communities. The
Committee identified overlaps in the description and distribution of the two nominated
communities and recommended they be jointly assessed. The workshop did not propose a
name for the ecological community; however, two suggestions were subsequently made:
Seasonal Freshwater Wetlands of the South-eastern Lowland Plains and the Lowland Swamps
in South-eastern Australia. The name should characterise the nature of these wetlands and its
geographic distribution. Consequently, the department proposes the compromise above as a
suitable name for the ecological community.
The landscape within which the seasonal wetlands occur are lowland plains in Victoria, south-
eastern South Australia (SA) and south-western New South Wales (NSW). In some places the
plains may be broken by local areas of higher relief, such as stony rises on the Victorian
Volcanic Plain. The ecological community is limited to lowland plains at elevations below 500
metres above sea level (asl).
The ecological community lies within an isohyet zone of 400 to 800 mm/year mean annual
rainfall. This covers all of the lowland plains in south-eastern SA and southern Victoria. It
also includes plains over much of the Wimmera and the south-eastern part of the Riverina,
south of Kerang and east of Deniliquin. The seasonal pattern of rainfall across the ecological
community‟s range is classified as Winter (wet winter/low summer rainfall) to Uniform (even
seasonal pattern) (Bureau of Meteorology, 2010). In many situations, the period of peak
rainfall leading to inundation of the wetlands is in winter to spring, but the variability of
rainfall is such that „unseasonal‟ rainfall events can lead to temporary inundation at other times
of the year.
The seasonal wetlands occur on poorly defined seasonal drainage lines or isolated / closed /
endorheic depressions. Their inundation is not dependent on flooding from riverine systems but
is fed primarily by local rainfall and may be influenced by groundwater. There may be
substantial groundwater influence in the formation of pools and the persistence of wetland
flora. Given the seasonal wetlands are driven by rainfall events supplemented by groundwater,
they are freshwater to slightly brackish systems. These wetlands are ephemeral, so are typically
dry for part of the year – i.e. they cannot be classified as either permanently wet or
permanently dry systems. The depth, duration and frequency of inundation are very variable,
reflecting prevailing weather conditions. In „typical‟ years, as defined by long-term climatic
trends, they may be inundated for a few months; inundation periods are longer in wetter years
and shorter in drier years. There may be little to no inundation for more than a year during
drought, as was the case for the drought in the mid-2000s.
The soils on which the seasonal wetlands occur are generally fertile but poorly draining clays.
They may be associated with a range of geologies, for instance clays derived from basalt for
occurrences in the Victorian Volcanic Plain or alluvial deposits in the Riverina. Many
examples of the community have „heavy‟ paludal soils formed locally by the long-term
presence of the wetlands themselves. In many cases, the wetlands occur in terrain characterised
by gilgais1 with the wetlands occur within localised Gilgai depressions.
Wetlands in the following landscapes are not part of the national ecological community
because they have different hydrological features and other characteristic flora species:
Wetlands that are strictly riparian or connected to a riverine system;
Coastal and near-coastal wetlands subject to tidal and estuarine influences;
Other inland wetlands associated with saline systems (generally at salinity levels above
3000 mg/L) and with a large proportion of halophytic species;
Wetlands in sandy contexts (e.g. on dune swales, wet heaths, etc.)
Wetlands on a limestone or calcarenite-derived substrate; and
Wetlands with a strong component of Sphagnum moss or peat, including peats derived
from other, non-mossy sources. [Note that highland peat swamps, currently listed as the
Temperate Highland Peat Swamps on Sandstone, are being reviewed with a view to
updating their definitions and national extent.]
The vegetation of these seasonal wetlands is generally treeless and dominated by a grassy
and/or herbaceous ground layer. The herbaceous species that dominate are characteristic of
wetter sites and are typically absent or uncommon within any adjoining dryland grasslands and
woodlands. The type of vegetation present is variable, but almost always emergent (i.e. above
the water), depending on the dominant lifeform present, and can be categorised as grassland,
sedgeland or forbland. The wetland may appear to be devoid of emergent vascular vegetation,
if it is observed immediately after filling. The diversity of the flora may range from species-
poor grasslands or sedgelands to diverse herbfields characterised by a suite of colourful forbs.
The wetland proper is delineated by the sometimes sharp boundary in soil, topography or
vegetation that distinguishes the wetland vegetation from any surrounding dryland vegetation,
whether native or modified, which contains no specialised wetland plant species and is rarely if
Canopy and mid layers (trees and woody shrubs)
Trees and shrubs are generally absent to sparse. When present, they are often confined to the
fringes or, sometimes, as scattered emergents within the wetland. Larger woody species that
may be present include Eucalyptus camaldulensis (River Red Gum), E. ovata (Swamp Gum) or
Muehlenbeckia florulenta (Tangled Lignum). Other tree and shrub species may occur
depending on the nature of the site, for instance a different suite of woody species may occur in
seasonal wetlands associated with stony knolls. The projective foliage cover of woody species
across the wetland proper is less than 10%.
This layer is the dominant layer and is characterised by native plant species that are adapted to
periodic inundation. The vegetation is typically dominated by a suite of native wetland
graminoids and forbs. The mix of species can vary from site to site but some graminoid and
Gilgai refers to surface micro-relief formed by the shrinking and swelling of clays during alternate
drying and wetting cycles. The surface eventually becomes covered by a repeated pattern of small
mounds and depressions that give the soil surface a 'pock-marked' appearance. Gilgai depressions are
sometimes also called crabholes or melonholes.
some forb species will always be present and it is the balance between certain graminoids and
forbs that determines the vegetation structure of the wetland as a grassland, sedgeland or
forbland. A list of the typical flora species present across the range of the ecological
community is given in Appendix A.
The graminoids present tend to be shorter (mostly <1 m tall) native species represented by one
or more of the following taxa:
Lachnagrostis spp. or
A variety of forb taxa may be present, depending on the nature and history of the site. Typical
forbs that may be present include wetland-associated species from the following genera:
Allittia, Asperula, Brachyscome, Calotis, Centella, Cotula, Craspedia, Epilobium, Eryngium,
Lobelia, Neopaxia, Pycnosorus and Villarsia. A more comprehensive list of forbs is given in
The ecological community is not present if the vegetation cover is dominated by tall native
graminoids typical of permanent wetlands, for instance Typha domingensis or Phragmites spp.,
or includes a substantial component of species typical of saline or samphire communities.
These are identified as different ecological communities to the seasonal wetland community
here described. However, it should be noted that Phragmites can be present in the seasonal
wetland as scattered emergents of low abundance. Also note the ecological community
generally lies within a salinity range of 0 to 3000 mg/L, above which almost all freshwater
aquatic fauna species disappear.
Ephemeral grassy wetlands provide habitat for a range of animals on the lowland plains. These
include various species of frogs, reptiles, waterbirds and aquatic invertebrates, notably
Crustacea in the groups Notostraca, Conchostraca and other Branchiopoda. Several fauna
species are listed as threatened or migratory species either nationally or within a State
3. Key Diagnostic Characteristics and Condition thresholds
The ecological community no longer exists at many sites where it was formerly present. In
many cases, the loss is irreversible because the site has been permanently converted to
cropland, developed pasture, artificial dam or has undergone some other substantial
modification that has removed its natural hydrological and biological characteristics. In other
cases, the ecological community now exists in a disturbed or degraded state. The degradation
may be sufficient that it is impractical to restore the site back to its former natural values,
especially if time, money or expertise are limited.
National listing focuses legal protection on the remaining patches of an ecological community
that are functional, relatively natural and in relatively good condition. Condition thresholds
help identify a patch of the threatened ecological community and when the EPBC Act is likely
to apply. They provide guidance for when a patch of the ecological community retains
sufficient conservation values to be considered a „Matter of National Environmental
Significance‟, as defined under the EPBC Act. This means that the referral, assessment and
compliance provisions of the EPBC Act are focussed on the most valuable elements of
Australia‟s natural environment.
Although very degraded/modified patches are not protected by listing under the EPBC Act, it is
recognised that patches that do not meet the condition thresholds may still retain important
natural values. Therefore, these patches should not be excluded from recovery and other
Key Diagnostic Characteristics
The ecological community exhibits the following key diagnostic characteristics.
• The landscape within which it occurs are plains on mainland south-eastern Australia, below
500 m asl and within the 400-800 mm/year annual rainfall zone.
• The wetlands occupy poorly defined seasonal drainage lines or depressions that are
episodically inundated, i.e. where the surface water does not persist throughout the seasonal
cycle. Their inundation is fed by rainfall events, often supplemented by groundwater, and is
not dependent on flooding from riverine systems.
• The salinity of the water varies from fresh to mildly saline, within the range 0 to 3000
• Woody tree and shrub species are sparse to absent, mostly occurring as fringing or
scattered individuals and accounting for <10% projective foliage cover across the wetland
• The ecological community is dominated by a combination of native wetland graminoids,
notably from the taxa: Amphibromus spp., Austrodanthonia duttoniana, Deyeuxia spp.,
Carex tereticaulis, Eleocharis spp., Glyceria spp., Lachnagrostis spp., and Poa
labillardierei; in conjunction with a range of forb species characteristic of wetland sites.
• Characteristic fauna that may be associated with the ecological community include
invertebrate groups that specialise in ephemerally wet sites: for instance, Crustacea in the
orders Diplostraca (clam shrimps) and Notostraca (shield shrimps).
• The ecological community is not associated with: riparian or riverine systems; coastal and
near-coastal sites subject to tidal and estuarine influences; limestone or calcarenite-derived
substrates; or a large presence of halophytic species or Sphagnum moss.
Given many of the flora species are difficult to identify, it is essential that assessors have
experience working with wetland systems in south-eastern Australia. Botanists and proponents
are expected to use their judgement based on their experiences to appropriately sample
wetlands depending on the nature of the site and particular circumstances. The following
survey protocols are recommended to as a guide to help determine wetland condition.
1) Survey should be done in the appropriate season when the site is, or has recently been
reasonably wet with standing water. This will usually be spring to early summer but can
vary depending on the rainfall pattern of particular seasons.
2) Undertake an overall assessment or inspection of the site.
3) Select areas that are representative of variability across the wetland site.
4) Sample vegetation using transects within each representative area.
This ecological community is highly variable because it is strongly influenced by seasonal
factors, notably rainfall patterns. Two sets of criteria for determining condition are therefore
presented. The first (A) applies when sites are wet or have been dry for a seasonal or relatively
short period. This is likely to apply in most years. The second (B) applies to times of prolonged
drought when the wetlands may be dry for extended periods, i.e. more than a year, and the
native wetland plants are likely reduced to desiccated tussocks or lie dormant as rootstocks or
Part A) During „typical‟ wet/dry cycles.
Step A1. Determine plant species indicative of relatively intact sites.
The intent here is to identify sites that remain in an intact or relatively undisturbed state based
on the presence of plant species that are relatively intolerant of disturbance, particularly due to
adverse human activities. Note that: 1) this step simply considers the presence/absence of
certain plant taxa and does not take the abundance of each species into account; and 2) it does
not consider native fauna due to problems in surveying and locating important fauna, which
may not always be evident. Since vegetation tends to be more persistent, it is a more reliable
indicator of the ecological community‟s presence.
i) Are two or more plant species from List 1 present within the wetland?
- If yes, the wetland is considered to be of exceptional quality due to the persistence of
plant species from List 1. Such sites are now rare and no minimum patch size applies.
They represent the sites of highest priority that merit protection under the EPBC Act.
- If no, go to ii).
ii) Does the wetland contain either: one plant species from List 1 and two or more plant species
from List 2, or three or more plant species from List 2 only?
- If yes, the wetland is considered to be of very good quality due to the persistence of
plant species in Lists 1 and/or 2. Such sites are now uncommon and no minimum patch
size applies. They represent sites of high priority that merit protection under the EPBC
- If no, go to Step A2.
Table 1. Native plant species present in the Lowland Seasonal Wetlands of South-eastern Australia
that are indicative of good condition and low disturbance of wetland sites. List 1 notes species that are
most disturbance sensitive and indicative of the highest quality. List 2 notes species that are relatively
less disturbance sensitive but still indicative of good quality for protection under the EPBC Act. The list
relates to Step A1 of the condition thresholds, above.
List 1 Native plant species. List 2. Native plant species.
Allitia cardiocarpa Asperula conferta s.l.
Brachyscome basaltica Asperula subsimplex
Calotis spp. Calocephalus lacteus
Cardamine spp. Eryngium vesiculosum
Craspedia paludicola Haloragis spp.
Diurus spp. Lobelia concolor
Helichrysum rutidolepsis s.l. Lobelia pratioides
Hypoxis spp. Marsilea spp.
Isoetes spp. Neopaxia australasica
Microseris spp. Potamogeton cheesmanii
Ottelia spp. Ranunculus inundatus
Pilularia novaehollandiae Stellaria angustifolia
Prasophyllum spp. Teucrium spp.
Senecio psiolocarpus Thelymitra spp.
Swainsona spp. Triglochin alcockiae
Utricularia spp. Triglochin striata
Note: the taxonomy of the species above follows that in APNI as at [insert date]. In cases where subsequent
taxonomic revisions may occur, the revised name of the taxonomic entities listed above will continue to apply.
Step A2. Determine dominant cover of native wetland plants in the ground layer
The intent here is to identify sites that can be considered to be remnant wetland vegetation
based on the predominant cover of native species in the patch.
Is the ground layer of the wetland dominated2 by perennial native graminoids and forbs
characteristic of wet sites? (refer to key diagnostic features, above, and Appendix A).
- If yes, the wetland retains sufficient natural cover and diversity. Go to Part C Minimum
patch size and landscape connectivity, below.
- If no, the wetland now comprises mostly non-native vegetation. It retains insufficient
natural values to be considered a matter of national environmental significance.
Part B) For extremely dry conditions (prolonged drought):
The presence of the wetland ecological community and delineation of its boundaries may be
difficult to determine during periods of prolonged drought. The above-ground wetland
vegetation may become largely absent or reduced to small desiccated vestiges that are difficult
to identify after extended periods without standing water. Underground rootstocks and seed
banks likely comprise the bulk of living biomass. However, landscape characteristics, such as
Dominated here means 50% or more of the total above ground cover of plants across the wetland site. When
sites are inundated, this includes vascular plant species rooted in the soil that emerge above the water, and that
remain submerged beneath any standing water. It does not include aquatic species that are freely floating on the
water surface, e.g. Lemna or Azolla, should these be present.
the presence of shallow depressions and drainage lines, may give the first indication whether
ephemeral wetlands are likely to occur.
Where possible, proponents should not undertake any assessments during a drought and should
wait for better conditions that would highlight the nature of the wetland. However, it is
acknowledged that delays due to seasonal conditions are not always practical. The following
steps during a drought may help to guide if the ecological community is likely to be present.
Step B1. Determine landscape position of the site.
Observations of the site and its surrounding landscape should show that it is clearly consistent
with the formation of ephemeral wetlands. There should be evident natural features such as the
presence of shallow depressions, drainage lines or gilgais that would foster temporary pooling
- If yes, then go to Step B2.
- If no, then the ecological community is unlikely to be present.
Step B2. Investigate the known or inferred history of the site.
Is the site known to be a natural wetland from existing information? For instance, the
composition of the site, when wet, is known from past vegetation surveys, detailed flora lists,
wetland directories, reliable modelling of pre-European vegetation, or on-ground evidence that
native wetland vegetation is present.
- If yes, and the information on plant species composition is sufficiently detailed and
there is no evidence of recent catastrophic changes to the site, then the site may be
assessed according to Step A2, above, using the existing information
- If no, or not as above, then go to Step B3.
Step B3. Determine evidence of catastrophic change to the site.
Has the site been adversely modified by works that have caused enduring or irreversible
changes to the hydrology, native vegetation or functionality of the site? [see list of catastrophic
changes, below]. Works that disrupt the soil structure and natural water drainage/retention
patterns at a site have implications for the long-term persistence of wetland flora and fauna.
- If yes, the site no longer retains its natural characteristics and is not part of the
- If no, then go to Step B4.
A catastrophic change to a natural wetland site is one that has or is likely to have a permanent
and irrecoverable adverse impact on the functionality of the wetland. The net impact is that the
site no longer functions as a seasonal wetland, resulting in a loss of native wetland species
diversity. Specific examples of catastrophic changes include (but are not limited to):
changed hydrology through major earthworks that cover more than half the former area of
changed hydrology through interception of overland water flows and reduction in run-off,
known or estimated to intercept more than half of the overland flow formerly destined for
conversion to cropland or improved pastures across the site;
conversion to tree plantations, on-site or nearby (within 100m), that exceeds half the size of
the wetland, and is likely to adversely impact on water table levels;
conversion to permanent developments, e.g. tip sites, infrastructure works, housing;
intensive grazing and associated impacts, e.g. pugging of soil; loss of palatable species,
weed invasion across most of the site;
inappropriate application of fertilisers, herbicides or pesticides;
inappropriate revegetation or salinity remediation activities, e.g. planting weedy species
such as tall wheat grass; and
inappropriate recreation activities, e.g. building bird-hides & associated “improvements” to
Step B4. Determine the nature of the vegetation surrounding the site.
Is the site surrounded by or adjoining a dryland native vegetation remnant3? For instance, the
site is next to natural temperate grassland, grassy woodland or other type of native vegetation
present in the region.
- If yes, the presence/persistence of adjacent native vegetation is evidence that the site is
unlikely to have been substantially disturbed and retains its natural values. The listed
ecological community is likely to be present. Go to Part C Minimum patch size and
landscape connectivity, below.
- If no, a natural wetland in good condition is unlikely to be present.
Part C) Minimum patch size, buffer zone and landscape connectivity
Minimum patch sizes are specified for certain ecological communities as a guide to help
determine national environmental significance, particularly where a community has become
fragmented into very small and often degraded remnants. Available patch size data for EVC
125 within all lowland plain bioregions in Victoria were used as a surrogate to investigate
likely patch size thresholds for the ecological community (Table 2). In terms of number of
patches, the ecological community exists as mostly small remnants under 0.5 ha in size.
However, most of the extent by area of the ecological community is captured by patches over
half a hectare in size. Note that the data in Table 1 may not represent all wetlands in EVC 125,
only those that could be detected by the mapping scale and survey methods used. The data are
likely to under-represent very small wetland patches.
Table 2. Patch size analysis based on data collated in 2007 for EVC 125 Plains Grassy
Wetland in the VVP, GleP, VRiv and MuF bioregions of Victoria.
category No patches % patches (ha) % area
0.01 - < 0.1
ha 2574 41.6 136.2 1.6
0.1 - < 0.5 ha 2126 34.4 471.0 5.6
0.5 - < 1.0 ha 473 7.6 332.7 3.9
1.0 - <10 ha 849 13.7 2732.4 32.4
10 + ha 163 2.7 4757.9 56.5
Total 6185 100 8430.2 100
A native vegetation remnant is a patch of vegetation that retains sufficient elements of its original
natural structure and native diversity after the broader landscape has been modified. For instance, it has
not been substantially or permanently replaced by exotic weed, pasture or crop species. A native
vegetation remnant in good condition would have the perennial vegetation cover of the ground layer
dominated by native species and a diversity of native species would be present.
Patch = Wetland Patch
Wetland patch or complex
B. Fine-scale complex of wetlands, e.g. in
gilgai terrain. The patch is the collective C. Wetland connected to or part
A. Isolated wetland in area of the complex and the minimum size of a native vegetation remnant.
landscape. Minimum patch is 0.5 ha. Note individual wetlands may be The minimum size of the
size is 0.5 ha. smaller than 0.5 ha. remnant+wetland is 1.0 ha.
Figure 1. Application of the term „patch‟3 to the wetland ecological community. Note that no
minimum patch size applies to sites identified as being of exceptional quality.
A. Single large wetland retained within a landscape of mostly cropland and other agricultural land uses (as per
B. Fine-scale complex of wetlands within a landscape of intervening natural temperate grassland subject to
sustainable production (as per Figs. 1B and 1C).
Figure 2. Application of the term „patch‟4 to the wetland ecological community – photographic views.
The following patch4 size considerations apply to this ecological community
C1. For exceptional to high quality patches that retain sufficient indicator species to meet
Step A1: no minimum size applies due to their rarity.
C2. For patches that retain sufficient ground-layer cover of native wetland vegetation to meet
the criteria for Step A2:
i) If the wetland occurs as a single isolated patch, the patch must be 0.5 ha or larger in
size (Figures 1A and 2A).
A patch is defined as a discrete and continuous area of the ecological community. However, a patch may include
small-scale disturbances, such as tracks, or small-scale variations in vegetation that do not significantly alter its
overall functionality. Depending on the nature of the landscape, this wetland ecological community may occur as
isolated natural wetlands or a complex of finer-scale natural wetlands (e.g. on gilgai landscapes) separated within
metres or tens of metres by non-wetland vegetation (native or non-native). In the former case, the patch size is the
area of the individual wetland. In the latter case, the patch is taken to be the collective area of the wetland complex
and a relevant measure of size is the total area of the wetlands proper plus the intervening non-wetland vegetation.
The close proximity of the wetlands means that they effectively act as a unit and the intervening non-wetland
vegetation is regarded as fine scale variation within a patch. See Figures 1 & 2.
ii) If the wetland occurs as a complex of many small wetlands in reasonably close
proximity, e.g. as happens in gilgai terrain, then the complex effectively functions as
a patch. The complex/patch must be 0.5 ha or larger in size (Figures 1B and 2B).
C3. Individual wetlands or wetland complexes smaller than 0.5 ha may also be included if
they are connected to, or part of, a larger native vegetation remnant and the wetland
otherwise meets the criteria for Steps A2 or B4. This applies where the wetland proper is
0.1 ha or more in size and the area of the native remnant plus wetland is 1 ha or more.
Note that the other vegetation types that make up a remnant are not considered to be
formally part of the listed wetland ecological community, although they may form part of
other listed national ecological communities (e.g. a listed natural temperate grassland or
grassy woodland system). However, they are important in providing landscape level
protection to the ecological community e.g. as buffers against further damage and to
promote movement of individual organisms and their genes
Outside of the situations described above, wetland is too small or degraded for consideration
as a matter of national environmental significance.
Buffer zone for the ecological community
To ensure the persistence of a patch of the ecological community a buffer zone of 50 metres
beyond the edge of the patch must also be protected. The definition of „patch‟ is given in
footnote 4, above.
A buffer zone is a contiguous area around the patch of the ecological community that is
important for protecting the integrity of the wetland. In areas where the ecological community
grades into an adjacent vegetation type, it may be difficult to determine the “edge” of the
ecological community. In such cases, the best judgement should be used to determine where
the ecological community ceases and an adjacent ecological community begins and establish
the buffer zone from there. The buffer zone should follow the shape of the wetland or wetland
The purpose of the buffer zone is to help protect and manage remnants of the national
ecological community. The edges of a patch are considered particularly susceptible to
disturbance and the presence of a buffer zone is intended to act as a barrier to further direct
disturbance. For instance, a buffer zone may help to protect the ecological community from
spraydrift (fertiliser, pesticide or herbicide sprayed in adjacent land), pollution, altered water
flows and other threats. Its purpose is not to extend the patch through regeneration. Changes in
land-use to the land that falls within the buffer zone must not have a significant detrimental
impact on the ecological community.
4. National context
The national ecological community primarily occurs on the lowland plains of Victoria, south-
eastern South Australia and south-western New South Wales (NSW). In particular, it largely
occurs within the lowland IBRA bioregions and subregions identified in Table 2 though some
outliers may extend into adjacent subregions.
Equivalent wetland units
Corrick and Norman (1980) Wetland classification scheme
This classification system was developed within Victoria largely to characterise habitats for
waterbirds, rather than to describe wetlands by vegetation or hydrological features. It has been
widely applied within Victoria and has the advantage of being supported by considerable
wetland inventory data. The national ecological community mostly falls within the Freshwater
meadows and Shallow freshwater marsh categories that are dominated by herbaceous
vegetation though may also include elements of Deep freshwater marshes under certain
circumstances, for instance during very wet seasons or where the landscape allows deeper
ponds to form in association with shallower wetlands (Table 3).
Directory of Important Wetlands
The directory collates information about nationally and internationally (Ramsar) important
wetlands in Australia. It uses a classification system slightly modified from the Ramsar
Convention to classify Australian wetlands into 42 types. The national ecological community
falls primarily into wetland type B10: Inland wetlands - Seasonal/intermittent freshwater ponds
and marshes on inorganic soils; includes sloughs, potholes, seasonally flooded meadows, sedge
marshes, claypan complexes, seasonally flooded canegrass/grass swamps. Some larger sites of
the national ecological community may be classified as wetland type B6: Inland wetlands -
Seasonal/intermittent freshwater lakes (>8 ha); floodplain lakes, billabongs, claypans.
Table 3. Likely distribution of the wetland ecological community by IBRA bioregion and subregion.
Note the ecological community may not extend across an entire bioregion or subregion but is limited by
the presence of landscape characteristics, e.g. the presence of appropriate depressions or gilgais, the
400-800 mm/year annual rainfall zone, and elevations below 500 m ASL.
IBRA bioregion IBRA Subregion (by State)
Victoria* NSW SA
Victorian Volcanic Plain Victorian Volcanic Plain Mt Gambier
South East Coastal Plain Gippsland Plain
Victorian Midlands Dundas Tablelands
Central Victorian Uplands
Naracoorte Coastal Plain Glenelg Plain Glenelg Plain
Murray Darling Depression Wimmera Wimmera
Riverina Victorian Riverina
Murray Fans Murray Fans
NSW South-western Slopes Northern Inland Slopes Northern Inland Slopes
* IBRA subregions are broadly equivalent to the Victorian bioregions.
Table 3. Wetland classification system after Corrick and Norman (1980; 1982). Parts of the
subcategories highlighted in bold are most likely to correspond with the national wetland ecological
community. Other subcategories are excluded on the basis of their strong salinity, dominance by woody
vegetation and association with riverine/floodplain sites, all of which fall outside the description of the
national ecological community.
Category (after Corrick & Norman (1980)) Sub-category Depth Duration of
Flooded river flats <2
These include many areas of agricultural land
that become temporarily inundated after
heavy rains or floods. Water may be retained
in local depressions for just a few days or for
Freshwater meadow 1 Herb-dominated < 0.3 < 4 months/
These include shallow (up to 0.3 m) and 2 Sedge-dominated year
temporary (less than four months duration) 3 Red gum-dominated
surface water, although soils are generally 4 Lignum dominated
waterlogged throughout winter.
Shallow freshwater marsh 1 Herb-dominated < 0.5 < 8 months/
Wetlands that are usually dry by mid-summer 2 Sedge-dominated year
and fill again with the onset of winter rains. 3 Cane grass dominated
Soils are waterlogged throughout the year 4 Lignum dominated
and surface water up to 0.5 m deep may be 5 Red gum-dominated
present for as long as eight months.
Deep freshwater marsh 1 Shrub-dominated <2 permanent
Wetlands that generally remain inundated to 2 Reed-dominated
a depth of 1 – 2 m throughout the year. 3 Sedge-dominated
5 Open water
6 Cane grass dominated
8 Red gum-dominated
Permanent open freshwater 1 Shallow <2 permanent
Wetlands that are usually more than 1 m 2 Deep >2
deep. They can be natural or artificial. 3 Impoundment
Wetlands are described to be permanent if
they retain water for longer than 12 months,
however they can have periods of drying.
Semi-permanent saline 1 Salt pan <2 < 8 months/
These wetlands may be inundated to a depth 2 Salt meadow year
of 2 m for as long as eight months each year. 3 Salt flat
Saline wetlands are those in which salinity 4 Sea rush-dominated
exceeds 3000 mg/L throughout the whole 5 Hypersaline lake
Permanent saline 1 Shallow <2 permanent
These wetlands include coastal wetlands and 2 Deep >2
part of intertidal zones. Saline wetlands are 3 Intertidal flats
those in which salinity exceeds 3000 mg/L
throughout the whole year.
Sewage oxidation basin
These include artificial wetlands used for
Salt evaporation basin
These include artificial wetlands used for salt
Equivalent State vegetation units
Victoria - Ecological Vegetation Classes (EVCs)
Victoria classifies its vegetation using a system of Ecological Vegetation Classes (EVCs)
(Department of Sustainability and Environment (DSE), 2007). An EVC may be further
subdivided into Floristic Communities. The EVC system also includes complexes, mosaic and
aggregate units for situations where specific EVCs cannot be identified at a site or at the spatial
scale used for vegetation mapping. EVC mosaics and complexes are included in the national
ecological community where they conform with the description of the national ecological
Victoria also has established benchmarks for each EVC (DSE, 2011). The primary intent of the
EVC benchmarks is to allow condition assessments to be made with respect to a reference
stand of a particular vegetation type. They are not a comprehensive description of an EVC but
do provide an accessible summary of its main features and ecology. In the case of wetland
communities, separate EVC benchmarks are available for vegetation quality assessment and
for the Index of Wetland Condition (DSE 2009). This assessment emphasises the IWC
benchmarks as these have been developed more recently and provide specific detail on wetland
A typology and field guide for wetland EVCs have been developed (DSE, 2009) along with
look-up tables that cross-reference the EVC system with the Corrick and Norman classification
(Table 4). The list of EVCs in Table 4 indicates those EVCs most likely to include patches of
the national ecological community in Victoria. The Victorian vegetation classification system
is complex and comprises a large number of wetland EVCs. It is possible that there are patches
of wetland that could be classified as other EVCs not listed in Table 4 but that may conform
with the national ecological community.
Table 4. Wetland Ecological Vegetation Classes (EVCs) most likely to correspond with parts of the
national ecological community.
EVC number & name Notes
125 Plains Grassy Wetland + complexes
- 755 Plains Grassy Wetland/Aquatic Herbland Complex Where grassy wetland grades into semi-permanent
- 767 Plains Grassy Wetland/Brackish Herbland Complex Where grassy wetlands grades into mildly saline sites
characterised by the appearance of halophytes.
- 959 Plains Grassy Wetland/Sedge-rich Wetland Complex
- 960 Plains Grassy Wetland/Spike-sedge Wetland Complex
306 Aquatic Grassy Wetland
647 Plains Sedgy Wetland + complexes
- 1010 Plains Sedgy Wetland/Sedge Wetland Complex
678 Ephemeral Drainage-line Grassy Wetland In gilgai systems along poorly defined drainage lines
within natural temperate grassland.
819 Spike-sedge Wetland
920 Sweet Grass Wetland
Elements of gilgai wetlands may also correspond with the national ecological community.
They include EVCs 778 Gilgai Wetland, 951 Ephemeral Gilgai Wetland and 956 Herb-rich
Gilgai Wetland and mosaics with dryland grassy woodland and grassland EVCs. Gilgai
wetland EVCs have not been incorporated within the Index of Wetland Condition or the
wetland EVC field guide to date and, consequently benchmarks and descriptions are not
readily available. They comprise very small depressions in the landscape where wetlands form
amongst the dryland grassy communities and may be considered too fine-scale for
consideration as a wetland proper. However, gilgai complexes that are spread over a larger area
>0.5 ha and occur in more open sites may correspond with the national ecological community.
NSW - Vegetation Classification and Assessment Database (NSW VCA)
A comprehensive vegetation classification system for all of NSW is only available at a broad scale,
to vegetation class (Keith, 2004). The national ecological community falls within the vegetation
class: Inland Floodplain Swamps. Despite the name of this vegetation class, it seems to cover a
range of wetland types, including ephemeral wetlands on lowland plains that may not depend on
connections to a riverine system for their water supply.
A finer-scale vegetation classification system, the NSW Vegetation Classification and
Assessment database (Benson et al., 2006; 2008), is in progress but presently does not cover all
of NSW, with the coastal and southern highland/alpine areas yet to be incorporated. The
database does have a complete coverage of the NSW Riverina where wetlands similar to those
in the Victorian Riverina are likely to occur. Two vegetation communities show similarity to
the national ecological community:
ID 47 Swamp grassland wetland of the Riverine Plain. The NSW VCA notes ID47 is
similar to the Victorian EVC 125.
ID 360 Gilgai wetland mosaic in the southern NSW South-western Slopes Bioregion. The
NSW VCA cross-refers ID360 with EVCs 235 Plains Woodland/Herb-rich Gilgai Wetland
Mosaic and 258 Alluvial Terraces Herb-rich Woodland/Plains woodland/Gilgai Wetland
Mosaic. This community appears to be a fine-scale intergrade between dryland Box-Gum
and Grey Box Grassy Woodlands and wetlands that form in small gilgai depressions. It is
limited to the far south of NSW between Lockhart and Albury, extending into north-east
Victoria, on the eastern edge of the NSW South-western Slopes Bioregions. Only those
elements where the tree canopy is more open to absent and at elevations less than 500 m
Other wetland communities occur in the southern Riverina but differ with respect to their
vegetation characteristics or hydrology. Many are associated more with floodplains and
riverine systems rather than isolated depressions fed by seasonal rainfall.
Seasonal inland wetlands may extend into the lower south-east of South Australia. The South
Australian Department of Environment and Natural Resources (SA DENR) is presently
revising its wetland classification from the existing broad wetland typology. Under its interim
wetland typology, the national ecological community would generally be classified as
freshwater meadows. Some occurrences, however, may be classified as grass sedge wetlands.
Both types include temperate palustrine systems that occur on flat landforms and both were
common in the south-east region though many remnants now exist in poor condition. SA
DENR provides the following information to describe their freshwater meadows and grass
Freshwater wetlands. Typically fresh, shallow (<50 cm deep) and filled with water for up
to 4 months in average years, but can be dry for over a year during drought. Often, but
not always, fringed with River Red Gums, with a ground layer that includes Baumea
arthrophylla, Eleocharis sphacelata, Myriophyllum spp., Villarsia reniformis, Triglochin
striata, and other wetland herbs. Underlain by sandy or clay soils and filled by local
runoff, supplemented with groundwater. Groundwater levels were historically close to the
surface in low lying areas but are now significantly lower in many areas due to water
extraction and extensive plantations.
Grass sedge wetlands. A broader wetland type that may be groundwater or surface water
driven. Tend to be wet for longer (at least 6-8 months, sometimes permanently) and are
often, but not always, large. They support a similar range of species to freshwater
meadows and the two types commonly occur in association, for instance a freshwater
meadow fringing a grass sedge wetland.
The biological surveys and biodiversity plan for the south east of South Australia (Croft et al.
1999; Foulkes and Heard 2003) provide a list of specific vegetation types, including
sedgelands and herblands in the region. The wetland vegetation communities that may be most
similar to national ecological community include:
SE0082 Cyperaceae sp., Gramineae sp. Mid Sedgeland;
SE0085 Juncus sp., Isolepis sp., Poa sp. Tall Sedgeland; and
Baumea juncea, Chorizandra enodis Sedgeland.
Equivalent state-listed communities
One ecological community listed under Victoria‟s Flora and Fauna Guarantee Act (1988)
overlaps with the national ecological community. This is the Herb-rich Plains Grassy Wetland
(West Gippsland) Community. This community has a swampy grassland/sedgeland ground
layer and ranges in structure from naturally treeless to a woodland or open forest with a tree
canopy of Eucalyptus camaldulensis (River Red Gum). Sites where the tree canopy is naturally
absent to sparse, would conform with the national ecological community as described above.
However, sites with a more developed tree canopy are not part of the national ecological
Victoria also lists another wetland community on lowland plains, the Red Gum Swamp
Community No. 1. This is a woodland to open forest with a tree canopy dominated by River
Red Gums over a ground layer dominated by wetland graminoids and forbs. Its description
(VSAC 1993) indicates that it is not part of the national ecological community because it has a
more developed tree canopy and its structure is, therefore, a woodland rather than open
grassland, sedgeland or forbland.
There are no provisions in the South Australian National Parks and Wildlife Act 1972 to list
ecological communities as threatened entities; however, a provisional list of threatened
ecosystems is maintained by SA DENR. It identifies two wetland communities that are
potentially threatened and may overlap with the national ecological community.
1. Baumea arthrophylla Sedgeland in drainage lines and depressions (identified as
vulnerable). This community is limited to the Naracoorte Coastal Plain bioregion.
Examples are found in Hacks Lagoon Conservation Park.
2. Freshwater wetlands including aquatic Herblands/Sedgelands (identified as endangered).
This appears to be a generic entry that acknowledges wetlands to be threatened across all
bioregions in SA, including the Naracoorte Coastal Plain in the south-east.
As at 1 November 2010, there were no similar seasonal wetland communities listed as
threatened on the Riverina plain under the NSW Threatened Species Conservation Act 1995.
Adjacent and/or intergrading vegetation types [to be completed]
Other wetland ecological communities may appear similar to the wetland ecological
community but are distinguished by certain features of floristic composition or landscape
Upland Wetlands of the New England Tablelands (New England Tableland Bioregion) and the
Monaro Tableland (South Eastern Highlands Bioregion). This ecological community is
nationally listed as Endangered. It occurs in depressions in the landscape that may be inundated
on a near permanent, intermittent (= seasonal), or ephemeral basis. The vegetation is treeless
and comprises grasslands and sedgelands dominated by species characteristic of wetter sites. A
number of species present in the Upland Wetlands ecological community also occur in the
Lowland Seasonal Wetlands (e.g. Amphibromus nervosus, Eleocharis acuta, Potamogeton
tricarinatus, Stellaria angustifolia). However, the Upland Wetlands are distinguished by their
presence outside of lowland plains. The occur on plateaux of mostly (but not limited to) basalt
substrates that lie above 700 m asl and have an annual rainfall of less than 1000 mm/year. The
Lowland Seasonal Wetlands occur on plains at lower elevations, typically <500 m asl with
drier mean annual rainfall.
The ecological community naturally occurred within a context of surrounding vegetation that
were mostly dryland grassy communities such as natural temperate grasslands and grassy open
woodlands These are distinct from the wetlands by the presence of a suite of dryland grass and
forb taxa, for instance Themeda, Austrostipa, Wahlenbergia and Chrysocephalum. In a number
of landscapes, these communities are listed as nationally threatened in their own right, notably
the Natural Temperate Grassland of the Victorian Volcanic Plain, Grassy Eucalypt Woodland
of the Victorian Volcanic Plain, and the Gippsland Red Gum Grassy Woodland and Associated
Native Grassland. All of these are recognised as a nationally critically endangered ecological
community. Clearing and other threats have removed the surrounding natural vegetation so
that, at many sites, the wetlands now occur within highly modified vegetation such as cropland
or improved pastures.
5. Significant Impacts and Recovery Actions
Unacceptable actions likely to result in a significant impacts
Unacceptable actions (within the ecological community unless otherwise indicated) include:
Planting exotic, invasive or inappropriate species in or near the community, e.g. Tall Wheat
Grass, and including trees and plantations;
Soil compaction due to machinery and/or stock;
Any cropping, including raised-bed cropping;
Filling-in of wetlands or works that disrupt its hydrology;
Clearing of native vegetation (e.g. to build houses or infrastructure such as roads);
Rock crushing and/or removal;
Draining / damming / deepening (excavating) in or near the community;
Conversion for recreation or other purposes (e.g. building up the sides to deepen water
Dumping of soil or garden and other waste to fill in and contaminate sites;
Inappropriate grazing regime (including intensifying, stock type, unseasonal);
Point source pollution (run-on);
Water interception for agricultural purposes;
Application of fertilisers, herbicides, pesticides, insecticides within the community or its
buffer zone; and
Extraction of groundwater (including bores) in and around the wetland or within its buffer
Weeds are especially problematic if they are: consistently present through wet and dry cycles;
not readily manageable; of if the weeds present change the nature of the wetland even during
wet cycles, for instance invasive tea-trees that convert grassy systems towards a shrubby
system over time.
Priority recovery actions
Reinstate the natural drainage system5;
Permanently protect wetland sites through legal agreements and stewardships (e.g.
Improve condition of degraded patches, as appropriate (e.g. rehabilitate through plantings);
Develop and implement site conservation plans with landholders / land managers;
Control weeds (sensitivity in wetlands);
Resolve conflicting management advice by government agencies / agronomists (e.g. where
advised to plant detrimental species such as tall wheat grass, phalaris);
Improve grazing management to achieve conservation objectives;
Implement field hygiene protocols to reduce contamination of sites (e.g. spread of weeds,
Consider extension programme to educate farmers, land managers;
Implement translocation protocols;
Realign fences to recognise natural wetland boundaries, where possible; and
Acknowledge and maintain the protection of sites on public lands.
6. Data relevant to assessment against criteria
Information from available State vegetation databases and publications were examined for
available information on their estimated pre-European and current extent of the vegetation
units identified above.
Note that in some cases, wetlands may be maintained by an unnatural drainage system. These may be due to
works undertaken so long ago that the wetland has now become reliant on the unnatural state.
Criterion 1: Decline in geographic extent
Table 5. Estimated decline in extent of the national ecological community. Based on data
available as at 31 January 2011.
a) by identified map/vegetation units.
State Veg/Map Unit Bioregion Pre-European Current Decline
(ha) (ha) (%)
Victoria EVC 125 Plains Grassy Wetland VVP 40,685 5,905 85.49
Victoria EVC 125 Plains Grassy Wetland VRiv 6,903 2,134 69.09
Victoria EVC 125 Plains Grassy Wetland GipP 5,316 405 92.38
Victoria EVC 125 Plains Grassy Wetland DunT 2,561 861 66.37
Victoria EVC 125 Plains Grassy Wetland MuF 1,149 304 73.51
Victoria EVC 125 Plains Grassy Wetland CVU 237 67 71.70
Victoria EVC 125 Plains Grassy Wetland Wim 201 95 52.74
Victoria EVC 125 Plains Grassy Wetland GleP 69 44 36.23
Victoria EVC 125 Plains Grassy Wetland WaP 33 2 93.94
Victoria EVC 125 Plains Grassy Wetland OtP 31 1 96.77
Victoria EVC 125 Plains Grassy Wetland NIS 13 3 76.92
Victoria EVC 125 Plains Grassy Wetland Gold 9 2 72.43
Victoria EVC 647 Plains Sedgy Wetland VVP 28,941 6,832 76.39
Victoria EVC 647 Plains Sedgy Wetland DunT 2,512 1,050 58.21
Victoria EVC 647 Plains Sedgy Wetland WaP 701 7 99.00
Victoria EVC 647 Plains Sedgy Wetland GleP 587 232 60.48
Victoria EVC 647 Plains Sedgy Wetland OtP 405 75 81.48
Victoria EVC 647 Plains Sedgy Wetland Wim 261 141 45.98
Victoria EVC 647 Plains Sedgy Wetland CVU 238 64 73.01
Victoria EVC 819 Spike-sedge Wetland MuF 635 595 6.20
Victoria EVC 819 Spike-sedge Wetland VRiv 5 4 16.67
Victoria EVCs 306, 678, 920 & Complexes No data yet
NSW VCA ID 47 RIV 35,000 17,500 50.00
NSW VCA ID 360 NSS 1,000 100 90.00
SA NCP No data yet
b) by IBRA Bioregion
Pre-European (ha) Current (ha) Decline (%)
VVP 69,626 12,737 81.71
RIV 43,692 20,537 53.00
SECP 6,486 490 92.44
VM 5,557 2,044 63.22
NSS 1,013 103 89.83
NCP 656 276 57.93
MDD 462 236 48.92
c) by State jurisdiction
Pre-European (ha) Current (ha) Decline (%)
Victoria 91,492 18,823 79.43
NSW 36,000 17,600 51.11
SA No data yet No data yet n/a
TOTAL 127,492 36,423 71.43
Indicative thresholds for Criterion 1.
Conservation status Threshold Indications from available data
Critically endangered >95% decline
Endangered >90% decline
Vulnerable > 70% decline Likely, based on available data. Estimated decline is
close to 70% (e.g. currently ~68%)
Not eligible <70%
Criterion 2: Small geographic distribution coupled with demonstrable threats
Threats were detailed in the nominations and noted at the workshop. They are ongoing and
likely to continue for the immediate to near future, at least.
Indicative thresholds for Criterion 2.
Conservation status Threshold Indications from available data
Critically endangered Extent of occurrence <10,000 ha
Area of occupancy <1,000 ha
Patch sizes generally <10 ha Likely, based on available data. Patch sizes
for EVC 125 are shown in Table 1.
Endangered Extent of occurrence <100,000 ha
Area of occupancy < 10,000 ha
Patch sizes generally <100 ha
Vulnerable Extent of occurrence <1 million ha
Area of occupancy <100,000 ha Based on available data, current AO is in
the order of 40,000 ha.
Not eligible Extent of occurrence >1 million ha Based on available data, EC extends from
Gippsland to SE SA to SW NSW.
Area of occupancy >100,000 ha
Specific questions to guide comments
1. Should the definition of this ecological community in the workshop report be altered to form
a broader or narrower national ecological community or to take account of regional variation?
- How would you amend the description and key diagnostic features of the national ecological
- Is the description of the ecological community provided in the workshop report sufficient to
identify it in the field and distinguish it from other ecological communities?
2. Can you provide further information about the national distribution of the ecological
3. Are the condition thresholds in the workshop report appropriate for this ecological
community? (Note that two sets of criteria are presented, one for „typical‟ wet seasons and one
for prolonged drought.)
- Can they be applied across its national extent? If not, how should they be modified?
- Are there any other characteristics which can be used to determine condition?
4. Do you consider that the ecological community meets the criteria for listing as threatened
under the EPBC Act? Please support your assessment with information relevant to the listing
criteria. (The criteria are described in the attached guidelines for nominating and assessing
ecological communities that can be downloaded here:
5. Can you provide further information about the nature and timeframe of threats operating
against the ecological community as identified in the workshop report and nominations?
6. Can you comment on the conservation actions that would abate the threats to, or assist the
recovery of, the ecological community?
7. Is there any recorded indigenous knowledge that relates to this ecological community? If so,
please provide references or contacts.
8. Are you able to provide further information about the faunal component of this ecological