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COOKS RIVER/CASTLEREAGH IRONBARK FOREST IN THE SYDNEY BASIN
BIOREGION: DRAFT DESCRIPTION
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1. DESCRIPTION OF THE ECOLOGICAL COMMUNITY
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The Cooks River/Castlereagh Ironbark Forest in the Sydney Basin Bioregion is a dry
sclerophyll open-forest to low woodland which occurs predominantly in the Cumberland
Subregion between Castlereagh and Holsworthy, as well as around the headwaters of the Cooks
River.
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1.1
Name of the ecological community
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The name of the ecological community is Cooks River/Castlereagh Ironbark Forest in the
Sydney Basin Bioregion. This reflects its structure and location and is the same name as it is
listed under the Threatened Species Conservation Act 1995 in New South Wales. Information
regarding the NSW ecological community can be found at:
http://www.environment.nsw.gov.au/determinations/CooksRiverCastlereaghIronbarkForestSyd
neyEndComListing.htm
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1.2
Location and physical environment
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Cooks River/Castlereagh Ironbark Forest in the Sydney Basin ecological community is
endemic to NSW, within the Cumberland subregion of the Sydney Basin Bioregion as defined
by version 7 of the Interim Biogeographic Regionalisation of Australia (IBRA v 7).
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The majority of the community is found on the Cumberland Subregion north and west of
Botany Bay towards Richmond. The largest patches occur in the Castlereagh and Holsworthy
areas. Smaller remnants occur in the Kemps Creek area and in the eastern section of the
Cumberland Subregion (e.g. upper Cooks River Valley).
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Geology
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The community occurs on clay-rich soils derived from predominantly Tertiary alluvium and on
Wianamatta Shale derived soils found next to Tertiary alluvium (NSW NPWS 2002; Tozer,
2003; NSW Scientific Committee, 2011). Tertiary Alluvium deposits produce less fertile
gravelly clay loam soils than the surrounding shales (Tozer et al., 2010). To a lesser extent, the
ecological community also occurs on Holocene Alluvium (NSW NPWS, 2002). The ecological
community grades into other communities where clay soils are very poorly drained, and where
the clay soils transition to more sandy or shale influenced soils (Tozer et al., 2010).
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Climate
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Cooks River/Castlereagh Ironbark Forest occurs below 100 m above sea level with mean
annual rainfall of 800-1000 mm (Tozer et al., 2010). The average January maximum
temperature for the relevant areas of the Cumberland Plain1 is 29.3°C and the average July
minimum temperature for those areas is 4.5°C.
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1.3
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Cooks River/Castlereagh Ironbark Forest is an open-forest to low woodland, dominated by
Eucalyptus fibrosa (Broad-leaved Ironbark) and Melaleuca decora (Paperbark) (NSW NPWS
2002; Tozer; 2003; Tozer et al., 2010; NSW Scientific Committee, 2011). E. longifolia
1
Vegetation
Mean average maximum (January) and minimum (July) temperatures from Bankstown, Holsworthy, Badgerys
Creek AWS, Badgerys Creek McMasters, Penrith Lakes and Richmond RAAF.
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(Woolybutt) is also often present (NSW NPWS, 2002; Tozer, 2003; NSW Scientific
Committee, 2011). The shrub stratum is relatively dense, and is dominated by M. nodosa
(Prickly-leaved Paperbark) and Lissanthe strigosa (Peach Heath), and to a lesser extent M.
decora (NSW NPWS, 2002). It also includes a range of ‘pea’ flower shrubs, including
Dillwynia tenuifolia, Pultenaea villosa (Hairy Bush-pea) and Daviesia ulicifolia (Gorse Bitter
Pea) (Tozer, 2003; NSW Scientific Committee, 2011). The ground layer is relatively sparse
and commonly includes Entolasia stricta (Wiry Panic), Lepidosperma laterale, Opercularia
diphylla, Dianella revoluta subsp. revoluta (Blue Flax-Lily), Themeda australis (Kangaroo
Grass), Microlaena stipoides var. stipoides (Weeping Grass) and Pratia purpurascens
(Whiteroot) (NSW NPWS, 2002; Tozer, 2003).
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Table 1: Characteristic plant species (NSW Scientific Committee, 2011; Royal Botanic
Gardens and Domain Trust, 2014). This is a list of characteristic plant species rather than
comprehensive list of all plants present in the ecological community. A particular patch may
not include all species on the list or may include other species not listed.
Plant form
Species name
Common name
Acacia binervia
Coast myall, Coastal myall, Coastal
wattle, Kai'arrewan (D'harawal)
Tree or shrub
Erect or spreading tree/ shrub
Tree to 15 m high
Tree to 30 m high
Tussocky perennial,
inflorescence to 1.2m high
Erect tufted or rhizomatous
perennial, inflorescence to 0.8
m high
Mat-forming shrub with
branches ascending to 15 cm
high with a spread of up to
1m
Erect, densely caespitose
perennials to c. 70 cm tall
Acacia falcata
Angophora bakeri
Angophora floribunda
Aristida ramosa
Narrow-leaved Apple
Apple, Rough-barked Apple
Purple Wiregrass
Aristida vagans
Threeawn Speargrass
Astroloma humifusum
Native Cranberry
Rytidosperma
setaceum Syn.
Austrodanthonia setacea Smallflower Wallaby Grass
Rytidosperma tenuius
Erect, caespitose perennial to
1.2 m high
Caespitose perennial, basal
foliage tussocky,
inflorescence to 1.5m high
Caespitose perennial, basal
foliage tussocky,
inflorescence to 1.2m high
Twining perennial herb or
slender vine to 3m high in
groundcover and midstorey
Shrub, 0.08–0.6 m high
Shrub or small to medium
tree, typically to 3m, rarely to
10 m high
Perennial, erect or prostrate
herb to 60 cm high
Syn. Austrodanthonia
tenuior
Austrostipa pubescens
Downy wattle
Austrostipa rudis
Billardiera scandens
Boronia polygalifolia
Bursaria spinosa
Hairy Apple Berry
Dwarf Boronia
Blackthorn, Boxthorn, Sweet Bursaria,
Kurwan (D'harawal)
Calotis cuneifolia
Purple Burr-daisy
2
Plant form
Species name
Common name
Shrub to 2 m high
Glabrous twiner with stems
c. 0.5 mm thick
Ground covering, creeping
fern with erect fronds to 30cm
Perennial herb, basal foliage
in a clump, inflorescence to 1
m high
Tufted perennial grass,
inflorescence to 1.2 m high
Spreading to erect shrub 0.3–
1 m high
Erect shrub 0.5–2.5 m high
Cassinia arcuata
Cassytha glabella forma
glabella
Cheilanthes sieberi
subsp. sieberi
Sifton Bush, Chinese Shrub
Erect shrub to 1m
Perennial plant, persistent
rootstock with prostrate or
twining herbaceous or softlywoody stems
Perennial plant, persistent
rootstock with prostrate or
twining herbaceous or softlywoody stems
Straggling or somewhat
shrubby, wiry, rhizomatous
perennial grass usually to 0.8
m high
Tufted perennial grass, basal
foliage with inflorescence to
c. 0.6 m high
Tree to 20 m high
Tree to 35 m high
Tree to 35 m high
Tree to 25 m high
Tree to 45 m high
Leafless shrub or small tree to
8 m high
Twiner, perennial with stems
non-stoloniferous
Erect or ascending perennial
herb 15–30 cm high
Erect herbs to 60 cm high
Groundcover or decumbent
herb to 10cm high
Short-lived herb to 50 cm
high
Spreading bushy shrub 1–3
m high
Decumbent to spreading
Poison rock fern, mulga fern
Dianella revoluta
Blueberry Lily, Blue Flax-Lily
Dichelachne micrantha
Shorthair Plumegrass
Dillwynia parvifolia
Dillwynia sieberi
Dillwynia tenuifolia
Einadia nutans
Climbing Saltbush
Einadia trigonos
Fishweed
Entolasia stricta
Wiry Panic
Eragrostis brownii
Eucalyptus capitellata
Eucalyptus fibrosa
Eucalyptus longifolia
Eucalyptus moluccana
Eucalyptus resinifera
Exocarpos
cupressiformis
Glycine clandestina
Brown's Lovegrass
Brown Stringybark
Red Ironbark
Woollybutt
Grey Box, Terriyergro (D'harawal)
Red mahogany
Cherry Ballart, Native Cherry
Slender Glycine
Gonocarpus tetragynus
Goodenia bellidifolia
Goodenia hederacea
subsp. hederacea
Ivy Goodenia, Forest Goodenia
Goodenia paniculata
Branched Goodenia
Hakea sericea
Needlebush
Hibbertia empetrifolia
3
Plant form
shrub to 30 cm high and 60100cm across
Decumbent or prostrate shrub
with branches to 30 cm long
Shrub to 3.5 m high
Erect branching herb to c. 40
cm high
Tufted perennial with erect,
leaf-like culms to 1m
Shrub or small tree, 2–5 m
high
Erect, densely branched
shrub to 1 m high
Shrub, 15–70 cm high
Tufted, sometimes robust,
perennial herb.
Tufted perennial herb,
slender to robust
Tall shrub or tree to 10 m
high
Shrub usually 1–4 m high
Slender, often tufted
perennial grass with rambling
stems and inflorescences to
0.7 m high
Slender to rarely robust
tuberous terrestrial herb,
usually 15–50 cm high
Species name
Common name
Hibbertia serpyllifolia
Kunzea ambigua
Laxmannia gracilis
Slender wire lily
Lepidosperma laterale
Leptospermum
trinervium
Leucopogon juniperinus
Lissanthe strigosa
Lomandra longifolia
Flaky-barked Tea-tree, Slender
Tea-tree
Prickly Beard-heath
Peach Heath
Spiny-headed mat-rush, honey reed
Lomandra multiflora
subsp. multiflora
Many-flowered Mat-rush
Melaleuca decora
Melaleuca nodosa
Microlaena stipoides
Prickly-leaved Paperbark
Weeping grass
Microtis parviflora
Notelaea longifolia
Shrub or tree to c. 9 m high
Small weak or procumbent
herb
Rigid erect, tuberous
ephemeral herb, 20–60 cm
high
Much-branched, erect shrub
to 5 m high
Tufted to tussocky perennial
grass with inflorescences to
0.7 m high
Tufted perennial grass with
inflorescences to 0.7 m high
Erect to spreading shrub up to
2m tall but usually less.
Erect shrub to 3 m high
Erect to spreading herb or
subshrub to 40 cm high
Decumbent to ± erect,
slender, annual herb, 8–15 cm
Hairy Guinea flower
Tick bush
Slender Onion Orchid
Large Mock-olive, Large-leaved
Olive
Opercularia diphylla
Orthoceras strictum
Ozothamnus
diosmifolius
Panicum simile
Bird's-mouth Orchid
Rice flower, white dogwood, pill
flower, sago bush
Two-colour Panic
Paspalidium distans
Persoonia nutans
Nodding geebung
Podolobium ilicifolium
Pomax umbellata
Poranthera microphylla
4
Prickly Shaggy Pea
Plant form
high
Glabrous, decumbent herb
Prostrate to erect shrub
Dwarf shrub or woody herb,
rarely more than 20cm tall
Perennial herb,
inflorescences to 70 cm high
Tall tree
Terrestrial, tuberous,
ephemeral herb with a
solitary leaf
Densely caespitose, leafy
perennials
Annual to perennial 0.2–1 m
high
Perennial tufted herb, 5–80
cm high
Tufted, arborescent herb
Species name
Common name
Pratia purpurascens
Pultenaea villosa
Rhytidosporum
procumbens
Stackhousia viminea
Whiteroot
Hairy Bush-pea
Syncarpia glomulifera
Thelymitra pauciflora
Themeda australis
Vernonia cinerea var.
cinerea
Wahlenbergia gracilis
Xanthorrhoea media
Slender Stackhousia
Turpentine
Slender Sun Orchid
Kangaroo grass, Durawi
(D'harawal)
Sprawling Bluebell, Australian
Bluebell
Grass Tree, Gulgadya (Cadigal)
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Persoonia nutans (nodding geebung) is listed as Endangered under the New South Wales
Threatened Species Conservation Act and the EPBC Act. Dillwynia tenuifolia is listed as
vulnerable under the NSW TSC Act.
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1.4
Fauna
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The diversity and abundance of fauna species across the Cumberland Subregion (where the
ecological community occurs) has declined. Prior to European settlement, the Cooks
River/Castlereagh Ironbark Forest ecological community likely supported a range of animal
species, including small mammals (particularly micro-bats), insectivorous and seed-foraging
birds, birds of prey, skinks, snakes, frogs and a large range of invertebrates. The vegetation
structure and species composition of the ecological community provides shelter, food and
nesting material for these animals, which in turn play important roles in the ongoing function of
the ecosystem. Many fauna species present (e.g. woodland birds) may not necessarily be
restricted to this ecological community but may also occur in adjacent vegetation communities
in the Cumberland Subregion. These species are likely to rely on the presence of other native
vegetation adjacent to patches of the ecological community for their continued persistence.
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No studies have specifically examined the fauna across the entire range of the ecological
community. However, a number of sources provide useful information on the fauna that have been
observed at certain sites and in the Cumberland Subregion more generally, including the Atlas of
NSW Wildlife.
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Reptiles and amphibians observed in the ecological community includes: Limnodynastes
dumerilii (Banjo Frog); Crinia signifera (Common Eastern Froglet); Ramphotyphlops
nigrescens (Blackish Blind Snake); Tiliqua scincoides (Eastern Blue-tongue); Diplodactylus
vittatus (Eastern stone gecko) (OEH Atlas of NSW Wildlife in Department of the Environment,
2014b).
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Bird species observed in the ecological community include: Gerygone mouki (Brown
Gerygone); G. olivacea (White Throated Gerygone); Myiagra rubecula (Leaden Flycatcher);
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Myzomela sanguinolenta (Scarlet Honeyeater); Neochmia temporalis (Red-browed Finch);
Lichenostomus leucotis (White-eared Honeyeater); Oriolus sagittatus (Olive-backed Oriole);
Pachycephala rufiventris (Rufous Whistler); Pachycephala pectoralis (Golden Whistler);
Pardalotus striatus (Striated Pardalote); Pardalotus punctatus (Spotted Pardalote); Aegotheles
cristatus (Australian Owlet-nightjar); Podargus strigoides (Tawny Frogmouth); Todiramphus
sanctus (Sacred Kingfisher); Dacelo novaeguineae (Laughing Kookaburra); and Daphoenositta
chrysoptera (Varied Sittella) (OEH Atlas of NSW Wildlife and BirdLife Australia Birdata in
Department of the Environment, 2014b).
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Micro-bat species observed in the ecological community include: Nyctophilus geoffroyi (Lesser
long-eared bat); Chalinolobus morio (Chocolate Wattled Bat); Vespadelus vulturnus (Little
Forest Bat); Tadarida australis (White-striped Freetail-bat) (OEH Atlas of NSW Wildlife in
Department of the Environment, 2014b).
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Marsupial species observed in the ecological community include: Wallabia bicolor (Swamp
Wallaby); Petaurus australis (Yellow-bellied Glider); Petaurus breviceps (Sugar Glider) (OEH
Atlas of NSW Wildlife in Department of the Environment, 2014b).
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Meridolum corneovirens (Cumberland Plain Land Snail), listed as endangered in NSW, has
been observed in the ecological community (OEH Atlas of NSW Wildlife in Department of the
Environment, 2014) and Litoria aurea (Green and Golden Bell Frog), listed as nationally
vulnerable and endangered in NSW, is known to occur in the ecological community (NSW
NPWS, 2004).
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Table 2: Nationally listed threatened fauna species that either may occur, are known to occur,
or have been observed in the area occupied by the ecological community (Department of the
Environment, 2014a; OEH Atlas of NSW Wildlife in Department of the Environment, 2014b)
Species name
Common name
EPBC Act status
Anthochaera Phrygia
Regent Honeyeater
Endangered
Botaurus poiciloptilus
Australasian Bittern
Endangered
Lathamus discolor
Swift Parrot
Endangered
Rostratula australis
Australian Painted Snipe
Endangered
Turnix varius
Painted Button-quail
Vulnerable
Falcunculus frontatus
Crested Shrike-tit
Vulnerable
Heleioporus australiacus
Giant burrowing frog
Vulnerable
Chalinolobus dwyeri
Large-eared Pied Bat, Large
Pied Bat
Vulnerable
Pteropus poliocephalus
Grey-headed Flying-fox
Vulnerable
Dasyurus maculatus
maculatus
Spot-tailed Quoll, Spotted-tail
Quoll, Tiger Quoll
(southeastern mainland
population)
Endangered
Phascolarctos cinereus
Koala (combined populations
of Queensland, New
South Wales and the
Australian Capital Territory)
Vulnerable
Potorous tridactylus
tridactylus
Long-nosed Potoroo (SE
mainland)
Vulnerable
Pseudomys novaehollandiae
New Holland Mouse, Pookila
Vulnerable
Hoplocephalus bungaroides
Broad-headed Snake
Vulnerable
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1.5
Key Diagnostic Characteristics and Condition Thresholds
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National listing focuses legal protection on remaining 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 assist in identifying a patch
of the threatened ecological community, determine when the EPBC Act is likely to apply to the
ecological community and to distinguish between patches of different quality.
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1.5.1 Key diagnostic characteristics
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The presence of dry sclerophyll forests (which include the Cooks River/Castlereagh Ironbark
Forest) in the Cumberland Subregion is intimately linked to the presence of Tertiary alluvial
gravels, sands and clays within the broader shale lithology of the central Sydney Basin (Keith,
2004). Rainfall is also a key determining factor, which has a most noticeable impact on the tree
layer composition (Keith, 2004).
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Key diagnostic characteristics for the ecological community are:
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
confined to the Sydney Basin Bioregion;
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
primarily occurs in elevations below 100 m above sea level;
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
occurs in the Cumberland Subregion with clay soils derived from predominantly Tertiary
alluvium and on Wianamatta Shale derived soils found next to Tertiary alluvium;
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
is a dry sclerophyll open-forest to low woodland typically dominated by an overstorey of
Eucalyptus fibrosa, Melaleuca decora and occasionally Eucalyptus longifolia; and
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
usually includes a moderate to dense shrub stratum, commonly including Melaleuca nodosa
and Lissanthe strigosa, and to a lesser extent Melaleuca decora.
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
the ground layer is variable and generally sparse with a mix of grasses and graminoids,
forbs, and low shrubs;
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
patches typically contain many of the plant species presented at Table 1 and may contain
fauna species presented in Section 1.4.
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1.5.2 Condition thresholds
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Condition classes and 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. This means that the referral,
assessment and compliance provisions of the EPBC Act are focussed on the most valuable
elements of the ecological community. Very degraded patches that do not meet the condition
thresholds will be largely excluded from national protection.
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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 may 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.
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44
< Note: exact vegetative cover, patch size and tree diameter at breast height (dbh) figures are to
be finalised through further data analysis and consultation.>
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3
4
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For Cooks River/Castlereagh Ironbark Forest in the Sydney Basin Bioregion, categories A and
B are considered moderate quality condition and the minimum thresholds for a patch of the
ecological community to be subject to the referral, assessment and compliance provisions of the
EPBC Act. Categories C and D are considered the minimum thresholds for a patch of Cooks
River/Castlereagh Ironbark Forest in the Sydney Basin Bioregion to be regarded as an example
of high quality condition.
7
Category and Rationale
A. Moderate condition class
Represented by medium to large-size
patch as part of a larger native
vegetation remnant and/or with mature
trees
B. Moderate condition class
Represented by medium to large size
patch with high quality native
understorey
C. High condition class
Represented by medium to large size
patch with very high quality native
understorey
D. High condition class
Represented by large size patch with
high quality native understorey
Thresholds
Patch size >0.5ha
And
>30% of the perennial understorey vegetation cover is made up of
native species.
And
The patch is contiguous with a native vegetation remnant (any native
vegetation where cover in each layer present is dominated by native
species) >1ha in area.
Or
The patch has at least one tree with hollows or at least one large locally
indigenous tree (>80cm dbh).
Patch size >0.5ha
And
>50% of the perennial understorey vegetation cover is made up of
native species.
Patch size >0.5ha
And
>70% of the perennial understorey vegetation cover is made up of
native species.
Patch size >2ha
And
>50% of the perennial understorey vegetation cover is made up of
native species.
Perennial understorey vegetation cover includes vascular plant species of the ground and shrub layers with a
lifecycle of more than two growing seasons. Measurements of perennial understorey vegetation cover exclude
annuals, cryptogams, leaf litter or exposed soil.
Contiguous means the patch of the ecological community is continuous with, or in close proximity (within 100 m),
of another patch of vegetation that is dominated by native species in each vegetation layer present.
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1.6
Area critical to the survival of the ecological community
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Given reduced extent of the already limited distribution of the Cooks River/Castlereagh
Ironbark Forest, the areas currently occupied are considered to be areas critical to the survival
of the community.
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1.7
Geographic extent
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Cooks River/Castlereagh Ironbark Forest has a naturally restricted distribution, and is often
found in small pockets within Castlereagh Scribbly Gum Woodland. Since European
settlement, the Cooks River/Castlereagh Ironbark Forest has undergone a significant reduction
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1
2
in extent (Table 3) having been cleared or substantially modified by urban and rural/residential
development or clay/shale extraction (NSW NPWS, 2004; Tozer, 2010).
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Table 3. Estimates of decline and extent of the Cooks River/Castlereagh Ironbark Forest based
on information in NSW NPWS (2002), excluding units recorded with tree cover only and no
understorey as condition thresholds would exclude these patches.
Pre 1750 ha (modelled)
Current ha
% remaining
12,185
1,011
8%
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9
Tozer et al. (2006, 2010) estimates the remaining extent to be 5-20 per cent of the pre-1750
extent.
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1.8
Surrounding environment and national context
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The Cooks River/Castlereagh Ironbark Forest ecological community is endemic to New South
Wales, being generally restricted to the Cumberland Subregion of the Sydney Basin Bioregion
(IBRA 7.1). The Sydney Basin Bioregion is on the central east coast of NSW and occupies
approximately 3,624,008 ha, or 4.5 per cent of NSW (NSW OEH, 2011). The Interim
Biogeographic Regionalisation of Australia (IBRA) divides the Australian continent into
bioregions and subregions. IBRA is endorsed by all levels of government as a key tool for
identifying land for conservation. More information regarding IBRA, including maps are
available at: http://www.environment.gov.au/topics/land/nrs/science-maps-and-data/australiasbioregions-ibra.
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Table 4: Equivalent map units in key references.
Tozer et
al., 2010
Tozer et al.,
2006
DSF P1
Castlereagh
Ironbark
Forest
DSF P1
Castlereagh
Ironbark
Forest
Tindall
et al.,
2004
Tozer, 2003
DSF 1
Map Unit 3
Castlereagh
Ironbark
Forest
NSW NPWS,
2002
Community
ID 3 Cooks
River/
Castlereagh
Ironbark
Forest
Benson 1992,
1994
NPWS, 1997
Shale/Gravel
Transition
Forest (9d)
Eastern Shale/
Sandstone
Transition
Forest
Castlereagh
Ironbark Forest
(9e)
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29
30
31
32
33
34
Cooks River/Castlereagh Ironbark Forest is included within the vegetation class: Cumberland
Dry Sclerophyll Forests (Keith, 2004).
Defining a patch
As noted above, Cooks River/Castlereagh Ironbark Forest generally occurs as small pockets
within Castlereagh Scribbly Gum Woodland (DSF p7). That community is present on freedraining, sandier soils. Where drainage is poor, the community transitions to Castlereagh
Swamp Woodland (DSF p4). While the community is present on shale-derived soils next to
Tertiary alluvium, as the depth of the alluvium decreases, Cooks River/Castlereagh Ironbark
Forest grades into Shale-Gravel Transition Forest (DSF p502) (Tozer et al., 2006).
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4
Using Tozer et al. (2006) SCIVI spatial model data2, excluding patches under 0.5 ha, the mean
patch size is 6.84 ha and the largest patch is 154.6 ha. Patches under 0.5 ha account for 73 per
cent of mapped patches and occupy 39.4 ha out of a total of 1052 ha (using Tozer et al. 2006
mapped extent).
5
Buffer zone
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A buffer zone is a contiguous area adjacent to an ecological community that is important for
protecting the integrity of the community. As the buffer zone lies to the outside, around the
community, it is not part of the national ecological community and is not formally protected as
a matter of national environmental significance. However, practical application of a buffer zone
is strongly recommended.
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The purpose of the buffer zone is to help protect and manage 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 weed invasion,
pollution and other threats.
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The recommended minimum buffer zone for the ecological community is 30 metres from the
edge of a patch. A larger buffer zone may be applied, where practical, to protect patches that
are of particularly high conservation value, or if patches are down slope of drainage lines or a
source of eutrophication.
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2. SUMMARY OF THREATS
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As noted above, Cooks River/Castlereagh Ironbark Forest is naturally restricted in distribution
(Tozer et al., 2006, 2010). In addition to this, the ecological community has been extensively
cleared (NSW NPWS, 2002; Tozer 2003; Tozer et al. 2006, 2010; Keith 2004). The Cooks
River/Castlereagh Ironbark Forest is also among the most affected communities from grazing
within the coastal rain shadow valleys of southeast New South Wales (Tozer et al., 2010).
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29
Rural-residential and industrial development continue to threaten the community (Tozer et al.,
2010) and it is expected that the growth of western Sydney will further impact the ecological
community (NSW DECCW, 2010).
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31
32
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Threatened ecological communities on the Cumberland Plain are more susceptible to
degradation due to increasingly isolated and small remnants that are more exposed to weed
invasion and problems created by high nutrient and sediment runoff from urban and industrial
areas (NSW DECCW, 2010).
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Rubbish dumping and high frequency fires due to arson also pose continuing threats to the
ecological community (Tozer et al., 2010).
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2
Note the majority of SCIVI is model data and ground truthing is variable across the landscape.
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Bibliography
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5
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Department of the Environment (2014a). Atlas of Living Australia. Records for LOT 101
Richmond Road, Windsor Downs NSW 2756, Australia. Accessed 21 May 2014.
http://biocache.ala.org.au/explore/your-area#33.646300743910764|150.79420038774413|14|ALL_SPECIES
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New South Wales National Parks and Wildlife Service (NSW NPWS) (2004) Cooks
River/Castlereagh Ironbark Forest. Information Guide. Accessed 14 May 2014.
http://www.environment.nsw.gov.au/resources/nature/EECinfoCooksRiverCastlereaghIronbark
Forest.pdf
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New South Wales Scientific Committee (2011). Cooks River/Castlereagh Ironbark Forest in the
Sydney Basin Bioregion - Determination to make a minor amendment to Part 3 of Schedule 1
of the Threatened Species Conservation Act. Accessed 11 May 2014.
http://www.environment.nsw.gov.au/determinations/cooksriver36a.htm
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Office of Environment and Heritage (NSW OEH) (2011). Sydney Basin Bioregion. Accessed
15 May 2014. http://www.environment.nsw.gov.au/bioregions/SydneyBasinBioregion.htm
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The Royal Botanic Gardens and Domain Trust (15 May 2014). PlantNET - The Plant
Information Network System of The Royal Botanic Gardens and Domain Trust, Sydney,
Australia (version 2.0). http://plantnet.rbgsyd.nsw.gov.au
36
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Tozer, Mark (2003). The native vegetation of the Cumberland Plain, western Sydney:
systematic classification and field identification of communities. Cunninghamia 8(1): 2003.
38
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Tozer, M. G., Turner, K., Simpson, C. C., Keith, D. A., Beukers, P., Mackenzie, B., Tindall, D.
& Pennay, C. (2006) Native Vegetation of Southeast NSW: A Revised Classification and Map
for the Coast and Eastern Tablelands. Version 1.0. Department of Environment & Conservation
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Tozer, M.G., Turner, K., Keith, D.A., Tindall, D, Pennay, C., Simpson, C., MacKenzie, B.,
Beukers, P., and Cox, S. (2010) Native vegetation of southeast NSW: a revised classification
and map for the coast and eastern tablelands. Cunninghamia (2010) 11(3): 359–406.
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Southeast NSW Native Vegetation Classification and Mapping - SCIVI VIS_ID 2230,
1:100,000, Tozer, et al., NSW DECC, 2006.
Department of the Environment (2014b). EPBC Act Protected Matters Search Tool. Report
created 21 May 2014.
New South Wales Department of Environment, Climate Change and Water (NSW DECCW).
(2010) Cumberland Plain Recovery Plan, Department of Environment, Climate Change and
Water (NSW), Sydney.
New South Wales Department of Environment and Conservation (DEC NSW). (2005).
Recovering Bushland on the Cumberland Plain: Best practice guidelines for the management
and restoration of bushland. Department of Environment and Conservation (NSW), Sydney.
New South Wales National Parks and Wildlife Service (NSW NPWS) (2002). Interpretation
Guidelines for the Native Vegetation Maps of the Cumberland Plain, Western Sydney, Final
Edition. NSW NPWS, Hurstville. Accessed 11May 2014.
http://www.environment.nsw.gov.au/resources/nature/cumbPlainMappingInterpguidelines.pdf
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