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ENVIRONMENTAL IMPACT ASSESSMENT GUIDELINES Grevillea juniperina subsp. juniperina Plants are generally killed by fire and The following information is provided to regeneration is only from seed. The assist authors of species impact production and accumulation of seed in statements, development and activity the soil seed bank and seed germination, proponents, and determining and consent therefore, are likely to be critical parts of authorities, who are required to prepare the life cycle. or review assessments of likely impacts on threatened species pursuant to the Inappropriate fire regimes are a primary provisions of the Environmental threat to the life cycle of G. juniperina Planning and Assessment Act 1979. subsp. juniperina . Urban development in These guidelines should be read in which buildings are located close to conjunction with the NPWS Information populations may result in the absence of Circular No. 2: Threatened Species fire or low fire frequency resulting in Assessment under the EP&A Act: The ‘8 reduced seedling recruitment. The Part Test’ of Significance (November smaller the remnant the more significant 1996). this impact is likely to be. High fire frequency (e.g. control burns to protect Survey buildings) is also likely to impact on seedling recruitment if there is Grevillea juniperina subsp. juniperina is insufficient time intervals between a small to medium sized shrub which can successive fires to allow the be readily identified in the field at any accumulation of seed in the soil time of the year. It is unlikely to be seedbank. Developments without an confused with any other species of adequate buffer or fire protection zone Grevillea growing in the region. between the bushland and buildings are Distinctive features include the often not likely to be compatible, therefore, spreading or horizontal habit, short with the fire requirements of the species. lateral branches and prickly, narrow and often bright green leaves. Distinctive The growth and maturation of plants of “spider” flowers may occur at anytime of G. juniperina subsp. juniperina may be the year in a range of colours including affected by any development or activity red, pink, yellow, pale orange and green. which impacts adversely on its habitat. Urban development, including road Potential habitat comprises woodland construction, in close proximity to areas on Wianamatta Shale and Tertiary populations is likely to cause degradation alluvium (often close to the boundary of habitat by overshading, altered between the two geologies), and is hydrology, increased soil nutrients, usually associated with lateritic gravels. introduction of weedy species, and Populations are often found in relatively dumping of fill and waste. High levels of open and/or disturbed sites and wetter disturbance often results in dense areas. Key associated species include regrowth of aggressive native or exotic Eucalyptus tereticornis, E. fibrosa, species, reducing suitable open habitat Melaleuca decora, Bursaria spinosa, conditions for G. juniperina subsp. Dillwynia sieberi, Daviesia ulicifolia, juniperina. Rural subdivision may result Goodenia hederacea and Themeda in grazing of habitat by domestic australis. animals, introduction of fill and high nutrient levels. Although larger plants of Life cycle of the species G. juniperina subsp. juniperina are Little information is available on the life usually left by animals it is likely that cycle of G. juniperina subsp. juniperina. young plants are more palatable. Sites of May 2002 G. juniperina subsp. juniperina.which considered significant. Sites of particular are actively grazed appear to have a significance would include the dominance of larger, mature plants with following: limited seedling recruitment. • Areas of intact habitat away from high disturbance areas. Threatening processes • Areas of intact habitat greater than 2 Clearing of native vegetation is a key ha. threatening process listed on Schedule 3 • Population sizes of >50 plants and a of the TSCA and relevant to G. varied age structure with active juniperina subsp. juniperina. Impacts recruitment of seedlings. may include direct loss of habitat and local populations, reduced size of Isolation/fragmentation populations, physical and genetic In view of the restricted distribution of isolation of populations and reduced size G. juniperina subsp. juniperina and its and quality of habitat. The core occurrence within a range of plant distribution of G. juniperina subsp. communities, it is likely that populations juniperina coincides with major growth were once well connected, at least within areas. The gradual loss of small areas of the core habitat area. Relatively intact habitat has a marked cumulative effect. corridors can still be identified, Remaining patches of G. juniperina particularly in the Blacktown-Mt.Druitt subsp. juniperina are surrounded by area. Populations of G. juniperina subsp. urban development and subject to high juniperina, however, are becoming levels of disturbance including rubbish increasingly isolated as bushland areas dumping, trampling, road works, changes are cleared or degraded. Isolation of in drainage, recreational activities, weed populations is likely to result in reduced invasion and inappropriate fire regimes. gene flow and low genetic diversity High fire frequency resulting in the which may affect long-term viability. disruption of life cycle processes and Due to limited natural seed dispersal loss of vegetation structure and (probably <-3 m) in G. juniperina subsp. composition is also listed on Schedule 3 juniperina, even minimal clearing may of the TSCA and should be considered in act as an effective barrier. The greater relation to G. juniperina subsp. the barrier the less potential for juniperina. High fire frequency is likely recolonisation of sites following local to result in the depletion of the soil seed extinctions. bank if intervals between fire events are Most developments will create barriers not sufficient for plants to grow to and include the construction of roads, maturity and produce seed. Frequent tracks, houses and factories. Activities fire may also promote the growth of such as mowing, frequent fires or the weedy species. Infrequent and/or low dumping of fill may also isolate intensity fires are also a threat to G. populations. Degradation of habitat is juniperina subsp. juniperina resulting in also likely to cause isolation of inadequate seed germination. populations in G. juniperina subsp. juniperina by creating barriers of dense Viable local population of the weed growth and reducing availability of species potential seedling establishment sites. The viable population size for G. juniperina subsp. juniperina is unknown. Regional distribution of the habitat. Until such information is available all G. juniperina subsp. juniperina is populations should be assumed to be restricted to the Sydney Basin Bioregion. viable. Limit of known distribution A significant area of habitat The northern limit of G. juniperina Until there is adequate protection of G. subsp. juniperina is at Pitt Town & the juniperina subsp. juniperina. all sites are western limit is around Londonderry. considered important and the habitat The southern and eastern limits are at May 2002 Kemps Creek and at Quakers Hill occur within three council reserves respectively. Old records extend further (Nurragingy, Dr Charles Mackay and east to the Prospect district, however, Durward Reserves) within the Blacktown these populations are now believed to be local government area, however, these extinct. are managed primarily as recreational reserves. Most other known sites of G. Adequacy of representation in juniperina subsp. juniperina occur on conservation reserves or other privately owned land or on similar protected areas Commonwealth land. G. juniperina subsp. juniperina is not considered to be One small population of G. juniperina adequately conserved. subsp. juniperina (11 plants) occurs at the edge of Castlereagh Nature Reserve Critical habitat in marginal habitat along the Northern Road. There is an unsubstantiated record Critical habitat cannot be declared for G. from Windsor Downs Nature Reserve juniperina subsp. juniperina as it is not (Haddin 1992) although if still present it listed on Schedule 1 of the TSC Act. appears to be uncommon. Populations For Further Information contact Threatened Species Unit Conservation Programs and Planning Division, Central Directorate NSW NPWS PO Box 1967, Hurstville NSW 2220 Phone 02 9585 6678. www.npws.nsw.gov.au References Benson, D & McDougall, L. (2000) Ecology of Sydney plant species Part 7b: Dicotyledon family Proteaceae to Rubiaceae. Cunninghamia 6(4):1058. Daniell, A. (1992). The garden of Dorian Gray – genetics and vegetation management. Urban Bushland Management – Into the melting pot (ponderings, processes and problems. Urban Bushland Management, Sydney. Makinson, R.O. (2000). Grevillea, Flora of Australia, 17A: (ABRS/CSIRO:Australia). McGillivray, D. (1993). Grevillea, a taxonomic revision. Melbourne University Press. Morris, E.C. (2000). Germination response of seven east Australian Grevillea species (Proteaceae) to smoke, heat exposure and scarification. Australian Journal of Botany. 48:179-189. Myerscough et. al. (2000). Ecology of Proteaceae with special reference to the Sydney region. Olde, P. & Marriot, N. (1995). The Grevillea Book. Kangaroo Press. Sinclair Knight Mertz (2000). Proposed Western Sydney Orbital Species Impact Statement. Prepared by Cumberland Flora & Fauna Interpretative Services and LesryK Environmental Consultants. IMPORTANT DISCLAIMER The NSW National Parks and Wildlife Service and the editor expressly disclaim all liability and responsibility to any person, whether a purchaser or reader of this document or not, in respect of anything done or omitted to be done by any person in reliance upon the contents of this document although every effort has been made to ensure that the information presented in this document is accurate and up to date. May 2002.

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