Conservation Advice for Eastern Suburbs Banksia Scrub of the Sydney Region (S266b of the Environment Protection and Biodiversity Conservation Act 1999)
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This ecological community was listed under the EPBC Act on 16 July 2000. This Conservation Advice was approved by the Delegate of the Minister on 01 October 2015. Conservation Advice for Eastern Suburbs Banksia Scrub of the Sydney Region (s266B of the Environment Protection and Biodiversity Conservation Act 1999) This Conservation Advice has been developed based on the best available information at the time this Conservation Advice was approved; this includes existing plans, records or management prescriptions for this ecological community. 1 CONSERVATION OBJECTIVE To mitigate the risk of extinction of the Eastern Suburbs Banksia Scrub of the Sydney Region, and help recover its biodiversity and function, through the protections provided under the Environment Protection and Biodiversity Conservation Act 1999 and through the implementation of the priority conservation actions outlined in Section 6. 2 DESCRIPTION OF THE ECOLOGICAL COMMUNITY The Eastern Suburbs Banksia Scrub of the Sydney Region ecological community is a predominantly sclerophyllous heath or scrub community, although, depending on site topography and hydrology, some remnants contain small patches of woodland, low forest or limited wetter areas. The ecological community is listed as endangered under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). It occurs in Sydney’s eastern and south-eastern suburbs, where it grows on perched, nutrient-poor, aeolian and highly podsolised sands associated with dunes and sand sheets of Quaternary and Pleistocene age. Clearing, fragmentation, changed fire regimes, weeds, feral animals, and other threats have reduced the ecological community’s historical floristic variability (Benson & Howell, 1990b; NSW Scientific Committee, 2002). Most of the ecological community has been destroyed by urbanisation and associated infrastructure, and it has also been heavily cleared for military purposes at North Head. Losses were also likely to have occurred due to sand mining (OEH, 2013b). The ecological community was originally described from the work of Benson & Howell (1990a). It was listed as endangered under the New South Wales Threatened Species Conservation Act 1995 (NSW TSC Act) in 1997 and under the EPBC Act on 16 July 2000. In 2002 the NSW TSC Act listing determination was updated. More recently, it has been studied and mapped in much greater detail by the NSW Office of Environment and Heritage, OEH (2013a, b), which identifies two vegetation map units: ‘Coastal Sand Mantle Heath’ (S_HL03) and ‘Coastal Sandplain Heath’ (S_HL04). Coastal Sand Mantle Heath covers much of the vegetation originally understood to be the ecological community within Sydney’s ‘eastern suburbs’, but also occurs elsewhere in the Sydney Basin to a relatively minor extent. Coastal Sandplain Heath has a wider distribution in the Sydney region between Port Stephens and the Illawarra, although a small portion coexists with Coastal Sand Mantle Heath in the area originally known to support the ecological community (OEH, 2013a). The EPBC Act-listed Eastern Suburbs Banksia Scrub ecological community occurs in the coastal areas of Sydney, primarily in the eastern suburbs, and at North Head. The OEH vegetation map unit Coastal Sand Mantle Heath (S_HL03) best aligns with the listed ecological community. However, vegetation that fits the EPBC Act definition of the Eastern Suburbs Banksia Scrub of the Sydney Region Conservation Advice – Page 1 of 10 This ecological community was listed under the EPBC Act on 16 July 2000. This Conservation Advice was approved by the Delegate of the Minister on 01 October 2015. ecological community outside the area of map unit S_HL03 is also accepted to be that ecological community for the purposes of the EPBC Act. The floristic description of the legally defined ecological community is broadly consistent with the work of OEH (2013a, b) in relation to S_HL03 Coastal Sand Mantle Heath vegetation map unit. The typical indigenous species of the ecological community are now best understood through the definition of that vegetation map unit. Coastal Sand Mantle Heath Shrubs include Leptospermum laevigatum, Banksia aemula, Lambertia formosa, Woollsia pungens, Acacia suaveolens, Banksia ericifolia subsp. ericifolia, Monotoca elliptica, Allocasuarina distyla, Bossiaea heterophylla, Dillwynia retorta, Philotheca buxifolia, Persoonia lanceolata, Acacia longifolia, Bossiaea scolopendria, Leucopogon ericoides, Melaleuca nodosa, Ricinocarpos pinifolius, Styphelia viridis and Philotheca salsolifolia. Small trees include Angophora costata and Corymbia gummifera. Groundcovers include Xanthorrhoea resinosa, Dampiera stricta, Haemadorum planifolium, Lepidosperma laterale, Lomandra glauca, Hypolaena fastigiata and Xanthosia pilosa. Cassytha pubescens is the only characteristic vine or climber. This vegetation community ‘has a diverse range of larger shrubs with coast tea-tree (Leptospermum laevigatum), wallum banksia (Banksia aemula), scrub she-oak (Allocasuarina distyla) and heath-leaved banksia (Banksia ericifolia) commonly recorded, though no single species dominates at all sites. The composition of the heath, such as the prominence of the heath-leaved banksia, appears to reflect a transitional environment between the sandstone headland heaths nearby and the heaths found on deeper dunes’ (OEH, 2013b). The total flora species list for the ecological community is larger than those given above, with many species present only in one or two sites, or in very small quantity. Furthermore, not all of the above-listed assemblage is likely to be present in any particular site, nor at any one time. For example, some species may only be present as seeds in the soil seed bank with no above-ground individuals present. The species composition of a site will be influenced by the size of the site and by its recent disturbance history. For a number of years after a major disturbance, dominance by a few species (such as Kunzea ambigua or Leptospermum laevigatum) may occur, with gradual restoration of a more complex floristic composition and vegetation structure over time. The balance between species will vary with the fire regime, particularly the fire frequency, interval and intensity (NSW Scientific Committee, 2002). Coastal heaths along the eastern seaboard on soils derived either directly from sandstone or, if aeolian, of younger age than those of the Eastern Suburbs Banksia Scrub, are outside the scope of the endangered ecological community. ‘The soils on which the community occurs are components of ancient dune systems formed from deposits of wind-blown sand. As a result of their age, they have been exposed to long periods of weathering and soil leaching, producing highly podsolised soils. These shallower dunes support a wallum heath community that is unlike those found on Pleistocene dunes elsewhere in the greater Sydney region’ (OEH, 2013b). Most coastal heaths are much lower in form than the typical Eastern Suburbs Banksia Scrub remnant. Coastal heaths characteristically contain a maritime floristic component that may include Baeckea imbricata, Correa alba and Westringia fruticosa. These three species are normally contraindicative of Eastern Suburbs Banksia Scrub, though they may occur in ecotonal and disturbed sites, and may have been inappropriately planted in remnants during reconstructive works. The vegetation, in particular banksias, provides habitat and food for many native animal species, including high densities of invertebrates on which reptiles, birds and some mammals Eastern Suburbs Banksia Scrub of the Sydney Region Conservation Advice – Page 2 of 10 This ecological community was listed under the EPBC Act on 16 July 2000. This Conservation Advice was approved by the Delegate of the Minister on 01 October 2015. feed (Skelton et al., 2003a; DECC, 2009b). Characteristic fauna include bandicoots; ringtail possums; native rats; nectar and insect-eating birds such as honeyeaters, fantails and scrubwrens; and reptiles such as skinks and snakes. Two NSW-listed Endangered Populations occur in the North Head area: Perameles nasuta (long-nosed bandicoot) and Eudyptula minor (little penguin) (Skelton et al., 2003a). 3 CONSERVATION STATUS The Eastern Suburbs Banksia Scrub of the Sydney Region ecological community is listed as Endangered under the EPBC Act. The listing is based on data collected prior to the EPBC Act. This conservation advice was prepared to reflect recent data, in particular, from OEH (2013a, b). The national Recovery Plan for the ecological community (DEC, 2004) estimated the original (pre-European) area to be 5300 hectares. As of 2004, the area extant was calculated to be 146 hectares, of which 33 hectares were in formal reserves. Owing to actions arising from the listing and the Recovery Plan, some remnants or parts of remnants have been added to the conservation estate, including at Malabar Headland and Randwick Environmental Park (DSEWPaC, 2009), though other high priority remnants remain outside suitably secure and managed reserves. The Coastal Sand Mantle Heath vegetation map unit (S_HL03) covers the majority of accepted occurrences of the ecological community as originally understood plus some additional areas. This map unit is estimated to be more than 90% cleared, with <2% original area in formal conservation reserves. Outside of reserves, an estimated 250 hectares remains across the Sydney region. The pre-clearing extent of the vegetation map unit can only be estimated because of the extent to which its former