1.3.2.1 Description


1.3.2.1.1 Introduction to assets by subgroup, class and data source

The total number of ecological water-dependent assets in the PAE of the Pedirka subregion is 992 (from a total of 1239 ecological assets in the asset list). Of the water-dependent assets, 772 assets are vegetation features, 205 assets are surface water features and 15 assets are groundwater features (Table 7). Most of the vegetation features are groundwater-dependent ecosystems (GDEs) and most of the surface water features are wetlands, wetland complexes or swamps. Of the ecological assets, 938 assets were assessed as dependent on surface water and 646 assets were assessed as dependent on groundwater. Of these assets, 346 assets were assessed as dependent or possibly dependent on surface water alone, 54 assets were assessed as dependent or possibly dependent on groundwater alone, and 592 assets were assessed as dependent or possibly dependent on both surface water and groundwater.

Table 8 summarises the ecological assets and their water dependence according to database source. Maps of the distributions of the key data sources are shown in Figure 12, Figure 13, Figure 14, Figure 15, Figure 16 and Figure 17. Total assets cover a large proportion of the 219,000 km2 area of the PAE, giving confidence that the asset register is a thorough basis for the assessment of potential impacts of coal resource developments during later stages of the BA. In some datasets, at least some large assets intersect with only a small part of the Pedirka PAE and extend far beyond the boundaries of the PAE. This is most strongly the case for the National atlas of groundwater dependent ecosystems (GDE Atlas) (subsurface) and the Water Asset Information Tool (WAIT) database, in which Great Artesian Basin (GAB) groundwater aquifers, recharge beds and dependent ecosystems extend far to the north, east and south of the Pedirka PAE.

Table 7 Summary of ecological assets within the preliminary assessment extent (PAE) of the Pedirka subregion, according to asset subgroup and class


Subgroup

Class

Number of water-dependent assets

Number of assets dependent on surface water

Number of assets dependent on groundwater

Groundwater feature

Aquifer, geological feature, alluvium or stratum

15

6

14

Surface water feature

Floodplain

13

13

0

Lake, reservoir, lagoon or estuary

20

20

0

Marsh, sedgeland, bog, spring or soak

66

26

65

River or stream reach, tributary, anabranch or bend

51

51

0

Waterhole, pool, rockpool or billabong

7

7

7

Wetland, wetland complex or swamp

48

43

10

Vegetation

Groundwater-dependent ecosystem

747

747

535

Habitat (potential species distribution)

25

25

15

Total

992

938

646

Data: Bioregional Assessment Programme (Dataset 1)

Table 8 Summary of ecological assets in the preliminary assessment extent (PAE) of the Pedirka subregion, according to asset data source


Dataset

Number of water-dependent assets

Number of assets dependent on surface water

Number of assets dependent on groundwater

Australian Hydrological Geospatial Fabric

37

37

5

Collaborative Australian Protected Areas Database (CAPAD)

10

10

7

A directory of important wetlands in Australia (DIWA)

6

6

5

Great Artesian Basin Groundwater Recharge

4

4

4

National atlas of groundwater dependent ecosystems (subsurface)

26

26

19

National atlas of groundwater dependent ecosystems (surface)

558

558

353

National Groundwater Information System

1

0

1

Birds Australia Important Bird Areas (IBA)

3

3

3

Northern Territory – Lake Eyre Basin – Wetlands Mapping

26

26

0

Queensland Lake Eyre Basin Rockholes and Waterholes in Queensland – Indigenous

1

1

1

Queensland Wetland Data Streams

10

10

0

SA Lake Eyre Basin Aquatic Ecosystems Mapping and Classification

34

34

0

SA Wetland Groundwater Dependent Ecosystem Classification

163

163

163

Threatened species listed under the Commonwealth’s Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act)

8

8

3

Threatened species listed under Queensland’s Nature Conservation Act 1992, excluding EPBC Act-listed species

3

3

1

Threatened ecological communities listed under the EPBC Act

1

1

1

WAIT Desert Channels

8

4

5

WAIT SA Arid Lands

93

44

75

Total

992

938

646

Data: Bioregional Assessment Programme (Dataset 1)

Figure 12

Figure 12 Collaborative Australian Protected Areas Database (CAPAD) assets in the Pedirka preliminary assessment extent (PAE)

Data: Bioregional Assessment Programme (Dataset 1)

Figure 13

Figure 13 A directory of important wetlands in Australia (DIWA) assets in the Pedirka preliminary assessment extent (PAE)

Data: Bioregional Assessment Programme (Dataset 1)

Figure 14

Figure 14 Great Artesian Basin Groundwater Recharge assets in the Pedirka preliminary assessment extent (PAE)

Data: Bioregional Assessment Programme (Dataset 1)

Figure 15

Figure 15 Map of Birds Australia Important Bird Areas (IBA) assets in the Pedirka preliminary assessment extent (PAE)

Data: Bioregional Assessment Programme (Dataset 1)

Figure 16

Figure 16 Threatened ecological communities listed under the Commonwealth's Environment Protection and Biodiversity Conservation Act 1999 in the Pedirka preliminary assessment extent (PAE)

Data: Bioregional Assessment Programme (Dataset 1)

Figure 17

Figure 17 Water Asset Information Tool (WAIT) database assets for Queensland and South Australia, and equivalent Geofabric database assets for the Northern Territory, in the Pedirka preliminary assessment extent (PAE)

Data: Bioregional Assessment Programme (Dataset 1)

1.3.2.1.2 Threatened ecological communities

Only one ecological community listed under the EPBC Act occurs in the Pedirka PAE. Management plans indicate that ‘The community of native species dependent on natural discharge of groundwater from the Great Artesian Basin threatened ecological community’ depends eponymously on groundwater. Assessment data based on all satellite imagery data layers provide independent corroboration that this ecological community is water dependent. Most of these discharge springs occur to the west of Kati Thanda – Lake Eyre, with the Dalhousie Springs group lying further north, between Oodnadatta and Finke (Figure 16).

1.3.2.1.3 Habitats of threatened species

Of the 18 species listed as threatened under the EPBC Act, 8 species were assessed to rely upon water-dependent habitats, with 5 species dependent on surface water, and 3 species dependent on both surface water and groundwater (Table 9). Application of the precautionary principle means that any species that is ‘possibly’ dependent on water in excess of incident rainfall is determined to be water-dependent and its habitat is included in the register of water-dependent assets. None of the three EPBC Act-listed species that are dependent on groundwater is exclusively associated with ‘The community of native species dependent on natural discharge of groundwater from the GAB threatened ecological community’. Instead, evidence for dependence on groundwater or surface water is much less clear cut. The species occur across a wide range of community types that are more commonly ephemeral rivers, creeks, swamps and floodplains than permanent waterbodies. Groundwater may contribute to the water supply in some of these community types, through contributions to subsurface baseflow in rivers and creeks, or to soil water in swamps and floodplains. In all these community types, determination of absolute dependence on water in excess of rainfall (i.e. flows down drainage lines and across floodplains) cannot be made with complete confidence, and in all cases the precautionary principle has been applied to assess these species’ habitats.

Of the five species listed as threatened under the Nature Conservation Act, excluding those also listed under the EPBC Act, three species were assessed to rely upon water-dependent habitats, with two species likely or possibly dependent on surface water, and one species possibly dependent on both surface water and groundwater (Table 10). Evidence for dependence on surface water or groundwater is not clear cut for most of these species. As for some of the species listed under the EPBC Act, species listed under the Nature Conservation Act occur across a wide range of community types that are more commonly ephemeral than permanent waterbodies, and may involve some degree of input from groundwater sources. In such community types, determination of absolute dependence on water in excess of rainfall cannot be made with complete confidence, and again the precautionary principle has been applied to assess these species’ habitats.

Table 9 Water-dependent threatened species listed under the Commonwealth’s Environment Protection and Biodiversity Conservation Act 1999 and within the preliminary assessment extent (PAE) of the Pedirka subregion

Although examples of individual species are listed, bioregional assessments consider the potential impact to the habitat of species not individual species per se.


Scientific namea

Common name

Dependence upon surface water

Dependence upon groundwater

Comments

Acacia latzii

Latz's Wattle

Possible

No

Occurs on shallow gravelly soils in small watercourses, gullies and rocky slopes

Ardea alba

Great Egret

Yes

Possible

Occurs in a wide range of wetland habitats, including freshwater and saline, permanent and ephemeral, open and vegetated

Calidris acuminata

Sharp-tailed Sandpiper

Yes

Unlikely

Occurs in lagoons, swamps, lakes, dams, waterholes, soaks, bore drains and bore swamps, saltpans and hyper-saline salt lakes

Eleocharis papillosa

Dwarf Desert Spike-rush

Yes

Possible

All records are from ephemeral wetlands, predominantly freshwater and semi-saline swamps

Erythrura gouldiae

Gouldian Finch

Yes

Possible

Associated with beds of grass around shallow waterholes, watercourses, soaks and springs

Macrotis lagotis

Greater Bilby

Possible

No

Historically associated with drainage systems, salt lake systems and other alluvial areas

Notoryctes typhlops

Itjaritjari

Possible

No

Few data on the habitat preferences of the Itjaritjari; may occupy sandy river flats where aeolian dunes occur nearby. River flats may be rich in food resources for the Itjaritjari

Rostratula australis

Australian Painted Snipe

Yes

No

Occurs in shallow freshwater (occasionally brackish) wetlands, both ephemeral and permanent, such as lakes, swamps, claypans, inundated or waterlogged grassland, saltmarsh, dams, and bore drains

Data: Bioregional Assessment Programme (Dataset 2)

aTypology and punctuation are given as they are used in the legislation.

Table 10 Water-dependent threatened species listed under Queensland’s Nature Conservation Act 1992 (but not listed under the Commonwealth’s Environment Protection and Biodiversity Conservation Act 1999) and within the preliminary assessment extent (PAE) of the Pedirka subregion

Although examples of individual species are listed, bioregional assessments consider the potential impact to the habitat of species not individual species per se.


Scientific namea

Common name

Dependence upon surface water

Dependence upon groundwater

Comments

Austrobryonia argillicola

Tobermorey Melon

Yes

Possible

Most abundant in seasonal swamps, clay pans and run-on areas, and riparian woodlands dominated by River Red Gum (Eucalyptus camaldulensis)

Epthianura crocea crocea

Yellow Chat

Yes

Unlikely

Birds feed within low vegetation in or near channels and basins, and are seen on the ground at the bases of sedges and on bare mud

Sclerolaena walkeri

A small shrub

Maybe

No

Occurs on saline river flats and floodplains

Data: Bioregional Assessment Programme (Dataset 2)

aTypology and punctuation are given as they are used in the legislation.

Last updated:
9 January 2019