Given that South East Coastal Plain Grassland is only known to occur on few sites, which are relatively small in area, it is unlikely that any animal species would be restricted to the ecological community. The grassy and damp nature of the ecological community, however, could provide an extension of habitat for native fauna that inhabit adjacent grassy woodlands, scrub or wetland sites. The nationally endangered Isoodon obesulus obesulus (southern brown bandicoot (eastern subspecies)) has been recorded in plains grassland habitat along the Clyde–Tooradin rail line (DSE, 2004a). Macropus giganteus (eastern grey kangaroo) occurs in some of the larger patches more distant from human settlement. Some of the fauna noted to occur in other nationally threatened ecological communities in Gippsland, notably the Gippsland Red Gum (Eucalyptus tereticornis subsp. mediana) Grassy Woodland and Associated Native Grassland (listed as critically endangered) and Seasonal Herbaceous Wetlands (Freshwater) of the Temperate Lowland Plains (also listed as critically endangered), may also extend into South East Coastal Plain Grassland. For instance, the nationally vulnerable Litoria raniformis (growling grass frog), which occurs in Seasonal Herbaceous Wetlands, can disperse widely into adjacent non-wetland habitats, especially when occupying more ephemeral wetlands (TSSC, 2012). It has also been listed as occurring in Gippsland Red Gum Grassy Woodland and Associated Native Grassland (TSSC, 2008), so it is likely that it would occur in the wetter South East Coastal Plain Grassland as well.
Fauna surveys have not been undertaken for most sites of the South East Coastal Plain Grassland. Information about fauna from available surveys and publications has been summarised at Appendix A.
1.6Key diagnostic characteristics and condition thresholds
The key diagnostic characteristics presented here summarise the main features of the South East Coastal Plain Grassland ecological community. These are intended to aid the identification of the ecological community, noting that a broader description is provided above.
National listing focuses legal protection on those patches of the ecological community that are most functional, relatively natural (as described by the ‘Description’) and in relatively good condition. Key diagnostic characteristics and condition thresholds (where these apply) assist in identifying a patch of the threatened ecological community, determining when the EPBC Act is likely to apply to the ecological community and distinguishing between patches of different quality. They provide guidance as to when a patch of a threatened ecological community retains sufficient conservation values to be considered as a Matter of National Environmental Significance, as defined under the EPBC Act. Patches that do not meet the minimum condition thresholds are excluded from full national protection. This means that the referral, assessment and compliance provisions of the EPBC Act are focussed on the most valuable elements of the ecological community.
The South East Coastal Plain Grassland has a number of local variants and may exhibit various degrees of disturbance and degradation. Natural variation and degree of degradation has been taken into account in developing the key diagnostic characteristics and condition thresholds.
Much of the South East Coastal Plain Grassland ecological community occurs in areas that have been intensively modified for various purposes: agriculture, urban development and infrastructure such as power stations and transport. Although very degraded/modified patches are not protected as the ecological community listed under the EPBC Act, it is recognised that patches that do not meet the condition thresholds may still retain important natural values and support the protection of those patches that meet minimum thresholds. They may also be protected through State and local laws or schemes. Therefore, these patches should not be excluded from recovery and other management actions. Suitable recovery and management actions may improve these patches to the point that they may be regarded as part of the ecological community fully protected under the EPBC Act. Management actions should, where feasible, also aim to restore patches to meet the high quality condition thresholds outlined below.
For EPBC Act referral, assessment and compliance purposes, the national ecological community is limited to patches that meet the following key diagnostic characteristics and condition thresholds.
1.6.1Step 1 Key diagnostic characteristics
A patch must include the following key diagnostic characteristics to be considered the ecological community:
2) The vegetation structure is a tussock grassland in which:
trees and larger shrubs (>1 metre tall) are sparse to absent, such that their projective foliage cover is 5% or less across the grassland patch; and
the dominant feature is a ground layer primarily comprised of herbaceous species.
3) The ground layer of the patch must contain3 four or more ground layer species from the indicative list at Table 2, including at least one of the key grass species Themeda triandra (kangaroo grass) and/or Poa labillardierei (common tussock grass).
The presence of the following species or features indicates that a patch is not the South East Coastal Plain Grassland.
Eucalyptus tereticornis (Gippsland red gum). This tree is characteristic of the Central Gippsland Plain and is associated with grassy communities that are drier in nature, notably the Gippsland Red Gum (Eucalyptus tereticornis subsp. mediana) Grassy Woodland and Associated Native Grassland.
A substantial presence of halophytic species, e.g. Distichlis distichophylla (Australian salt-grass). These are associated with samphires, estuarine flats or other saline or brackish sites and are classified as different EVCs, e.g. EVC 914 Estuarine Flats Grassland.
Grasslands derived from cleared woodland or heathland, for instance EVC 55 Plains Grassy Woodland, EVC 175 Grassy Woodland, or EVC 793 Damp Heathy Woodland where the canopy has been removed but the understorey remains intact.
Grasslands with higher (more than 10%) cover of small to medium shrubs, that may be considered heathland communities rather than grassland, e.g. EVC 710 Damp Heathland.
Grasslands associated with calcareous sands and loams (e.g. on the Yanakie Isthmus) or coastal grasslands on dune swales and coastal headlands.
General notes on the definition of South East Coastal Plain Grassland
The vegetation structure of the South East Coastal Plain Grassland ecological community is a tussock grassland, with the dominant tussock grasses being kangaroo grass and/or common tussock grass. Kangaroo grass usually is common at drier sites with common tussock grass becoming more prevalent at wetter sites. A range of other native grasses and forbs can be present and may be locally dominant in pockets within the grassland. The ecological community is associated with damp sites, primarily on Quaternary heavy fluvial sediments (active or ancient floodplains). It does not extend onto soils that are sandy or calcareous. The region across which it occurs has an elevation typically less than 100 metres above sea level and receives a mean annual rainfall usually greater than 550 mm/year.
1.6.2Step 2 Condition thresholds
Condition thresholds provide guidance for when a patch of a threatened ecological community retains sufficient conservation values to be considered as a Matter of National Environmental Significance, as defined under the EPBC Act. Patches that do not meet the minimum condition thresholds are excluded from full national protection. This means that relevant referral, assessment and compliance provisions of the EPBC Act are focussed on the most valuable elements of the ecological community. However, as noted above, such patches may still retain important natural values and should not be excluded from management actions, particularly where their inclusion would support the protection of patches that meet minimum thresholds.
The minimum condition thresholds specified below acknowledge that the South East Coastal Plain Grassland ecological community is limited to a relatively small number of known sites that are fragmented and small in size, as well as taking into account the seasonally variable and dynamic nature of this ecological community.
The minimum condition thresholds are:
30% or more of the perennial ground layer vegetation cover comprises native species; and
The minimum patch size for the ecological community is 0.04 hectares.
The following factors should be taken into consideration when evaluating the key diagnostic characteristics and condition thresholds. This information is provided to help environmental assessment officers, consultants and others with surveying the ecological community and assessing whether actions are likely to be significantly detrimental to the ecological community.
Patch. A patch is defined as a discrete and continuous area of the ecological community. However, patches can be spatially variable and are often characterised by one or more areas within a patch that meet the condition threshold criteria that are surrounded by areas of lower quality. Therefore a patch may include small-scale interruptions or disturbances, such as roads, tracks or breaks (including exposed soil, leaf and other plant litter, cryptogams), watercourses/drainage lines or localised variations in vegetation, e.g. small clumps of weeds in a drainage line, that do not significantly alter its overall functionality.
Buffer zone: A buffer zone is a contiguous area adjacent to a patch of the ecological community that is important for protecting the integrity of the ecological community. As the buffer zone lies to the outside, around the patch, it is not part of the national ecological community and is not formally protected as a matter of national environmental significance. Where the buffer on a particular property is subject to existing land uses, such as cropping, ploughing, grazing, spraying, etc., they can continue. However, practical application of a buffer zone is strongly recommended.
The purpose of the buffer zone is to help protect and manage the national ecological community. The edges of an ecological community 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 weed invasion, pollution (e.g. from fertiliser residues) and other threats.
The recommended minimum buffer zone for the South East Coastal Plain Grassland ecological community is 30 metres from the edge of a grassland patch. A larger buffer zone should be applied, where practical, to protect patches that are of very high conservation value, or if patches are down slope of drainage lines or a source of eutrophication.
Revegetated areas. Revegetated or replanted sites are not excluded from the listed ecological community so long as the patch meets the key diagnostic characteristics plus condition thresholds above. It is recognised that revegetation often requires longer-term effort and commitment and it may take some time for a degraded patch to reach a high quality condition.
Timing of surveys. The timing of surveys is important with respect to disturbance history because the ecological community can vary markedly in appearance, for instance many species may only be evident during the spring flowering season; also heavy seasonal rainfall may temporarily result in seasonal wetlands. Ideally, surveys should be repeated in more than one season and more than one year to ensure that the flora of a patch is fully and adequately sampled and that potential occurrences of the community are rigorously tested against the condition thresholds. It is important to note what kind of disturbance may have happened within a patch, and when that disturbance occurred, as far as possible.
Sampling protocols. Thorough and representative on-ground surveys are essential to accurately assess the extent and condition of the ecological community. Patches can vary markedly in their shape, size and features that appear within a given patch. As a general principle, sampling should address the following:
any significant variation in the vegetation, landscape qualities and management history (where possible) across the patch, for instance localised weed cover, drainage lines, grazed areas, saline zones; and
the appropriate size and number of plots or transects to provide a representative sample across the full extent of the patch.