THREATENED SPECIES SCIENTIFIC COMMITTEE Established under the Environment Protection and Biodiversity Conservation Act 1999 The Minister’s delegate approved this Conservation Advice on 16/12/2016. Conservation Advice Gossia gonoclada angle-stemmed myrtle Conservation Status Gossia gonoclada (the angle-stemmed myrtle) is listed Endangered under the Environment Protection and Biodiversity Conservation Act 1999 (Cwlth) (EPBC Act) effective from the 16 July 2000 . The species was eligible for listing under the EPBC Act as on 16 July 2000 it was listed as Endangered under Schedule 1 of the preceding Act, the Endangered Species Protection Act 1992 (Cwlth). Species can also be listed as threatened under state and territory legislation. For information on the current listing status of this species under relevant state or territory legislation, see http://www.environment.gov.au/cgi-bin/sprat/public/sprat.pl . The main factors that are the cause of the species being eligible for listing in the Endangered category are its small population size and restricted distribution . Description The angle-stemmed myrtle is a tree growing to 18 m tall. The bark of the trunk is smooth to flaky, pale brown, reddish, orangish, or gray. Branchlets are distinctly four-angled to laterally compressed and leaves are slightly discolorous, matte or slightly glossy above and matte below. The winged branchlets, slightly retuse leaf apex and five merous flowers distinguish G. gonoclada from other species of the genus in south-east Queensland (Snow et al., 2003). Distribution The angle-stemmed myrtle is endemic to south-east Queensland along the lower reaches of the Brisbane and Logan rivers. The species formerly occurred around Moggill and New Farm in Brisbane but there have been no recent discoveries in these areas (McNeill 2001). There are currently eight known populations with 72 individual wild plants within these (Ecosure 2016). The species occurs or may occur in the following mapped Regional Ecosystems in south-east Queensland; 12.1.1, 12.1.3, 12.3.1, 12.3.7, 12.3.7a, 12.3.11, 12.3.11a, 12.5.13a, 12.11.10, 12.11.3 and 12.11.3a (Queensland Herbarium 2015). Relevant Biology/Ecology The angle-stemmed myrtle is naturally found on sloping metamorphic or flat alluvial terraces of (largely) permanent waterways, which experience some degree of tidal influence at an elevation of 5 to 70 m (McNeill 2001; ILM 2016; LCC 2015). The species appears to have a preference for well-drained clay soils derived from metamorphosed sediments and Cainozoic or alluvial deposits (ILM 2016). The species flowers in October through to December, fruiting in January through to early April. The fruits remain viable for only a short period (McNeill 2001). Despite its small population size, there are high levels of genetic diversity in the angle-stemmed myrtle relative to other species now assigned to Gossia (Shapcott & Playford 1996). The unspecialized flowers, similar to those of many species in the Myrtaceae, suggest that insects, most likely bees, beetles, thrips and flies are pollinators (Beardsell et al., 1993; Wallace & Peloso 2004). The species regenerates vegetatively from stem suckers following damage to the main stem. Seed recruitment levels are low and the germination period is 8 - 60 days from the time of sowing, with a success rate ranging from 0-95 percent (McNeill 2001). Gossia gonoclada (angle-stemmed myrtle) Conservation Advice Page 1 of 5 Threats The key threats impacting on the angle-stemmed myrtle include the spread of myrtle rust, unsympathetic land use activities and the spread of weeds (Table 1). Table 1 – The key threats impacting the angle-stemmed myrtle in approximate order of severity of current risk, based on available evidence. Threat factor Threat Evidence base type and status Disease Myrtle rust known The angle-stemmed myrtle is extremely susceptible to myrtle (Puccinia rust (Pegg et al., 2014). There is variation in the severity of psidii ) myrtle rust disease across its distribution, but in the region controlled by Logan City Council it has had a negative impact on the health of approximately 75% of the remaining population and has severely impacted upon the reproductive success of the species (T. Taylor, pers.comm., 2016).There also appears to be a significant interaction between myrtle rust disease and drought with 10 trees dying at one location within two months in 2016 (T. Taylor, pers.comm., 2016). Land use activities Habitat loss historical Habitat of the angle-stemmed myrtle has historically been lost and and through urban expansion (McNeill 2001; BCC 2005). degradation known Neighbouring development may impact the species through disturbance to drainage/soil water regimes and various potential consequences of recreation, and vandalism (LCC 2015). Land use adjacent to sites may increase nutrient loads from run off and livestock grazing can result in soil compaction degrading habitat (BCC 2005). Rubbish dumping and slashing has been a problem at some sites in the past (McNeill 2001). Weeds Habitat known Remnant riparian vine forest within the species distribution is degradation often infested on the edges with hiptage (Hiptage and benghalensis ), cats-claw creeper (Macfadyena unguis-cati ), competition balloon vine (Cardiospermum grandiflorum ) and climbing asparagus (Asparagus africanus) (McNeill 2001). Lantana (Lantana camara ), broad-leafed pepper tree (Schinus terebinthifolius ), broad-leaved privet (Ligustrum lucidum ) and camphor laurel (Cinnamomum camphora ) can also invade habitat and outcompete the angle- stemmed myrtle (RCC 2014). Additionally, morning glory ( Ipomoea cairica ), coral berry ( Rivina humilis ), Chinese celtis ( Celtis sinensis ), Brazilian nightshade ( Solanum seaforthianum ), ochna ( Ochna serrulata ), Guinea grass ( Megathyrsus maximus ), para grass (Brachiaria mutica ), broad leaf paspalum ( Paspalum spp. ), signal grass ( Urochloa decumbens ) and trad (previously wandering jew) ( Tradescantia fluminensis ) affect the survival, growth and reproduction of the species (LCC 2015). Conservation Actions The Logan City Council is playing a key role in the conservation of the angle-stemmed myrtle including the protection of all Gossia gonoclada trees and their habitat through the Primary Gossia gonoclada (angle-stemmed myrtle) Conservation Advice Page 2 of 5 Vegetation Management Area overlay of the Logan Planning Scheme 2015, new plantings and weed suppression activities at sites and ongoing monitoring and surveys resulting in the identification of new populations. Bushland care groups around Brisbane also undertake work at various sites to manage habitat for the angle-stemmed myrtle and are supported by the Brisbane City Council. Recovery criteria outlined for the angle-stemmed myrtle in its former recovery plan stated that the wild populations were to be increased to 500 individuals from 73 original trees (McNeill 2001). Since 2001 a total of 350 new plants have been planted as part of revegetation projects taking the total to 423 trees (T. Taylor, pers.comm., 2016). In Logan City Council, 198 trees were planted as part of re-vegetation projects. Currently the number of surviving trees is low (71 wild individuals and 158 planted specimens), not fulfilling the aims of the initial recovery program (T. Taylor and J. Napier, pers.comm., 2016; Ecosure 2016). Some plantings died soon after planting, some were killed in tree falls and some were killed in the floods of 2013. Others have died as a result of myrtle rust outbreaks and recent drought (T.Taylor, pers.comm., 2016). The Logan City Council is in the process of developing a recovery plan for the angle-stemmed myrtle in the Council area (L. Veage, pers.comm., 2016; Ecosure 2016). Conservation objectives Increase the number of angle-stemmed myrtle in the wild through activities in habitat that promote plant health and natural recruitment, supported by the propagation and replanting of specimens. Ensure appropriate ecological assessment, reporting and surveys are adopted for developments proposed within the range of this species to avoid direct and indirect impacts on angle-stemmed myrtle and its habitat. Conservation and Management priorities Disease o Reduce the spread of myrtle rust at known sites through avoiding or minimising vehicle use, cleaning equipment and clothing, implementing wash down procedures before entering sites, consideration of fungicide control and or removing and disposing of diseased plants at sites and monitoring populations (whilst being mindful of limiting visitation to sites). Land use activities o Protect angle-stemmed myrtle populations on privately-owned lands through available council acquisition and conservation partnerships. o Install fencing at sites where appropriate to constrain stock and public access and minimise spread of disease. Weeds o Conduct hand weeding and spraying at sites to control the spread and impact of invasive species. Stakeholder Engagement o Support the Logan and Brisbane City Council and bushland care groups in planning, collaborating on and implementing conservation actions for the angle-stemmed myrtle under their relevant conservation action statement and recovery plan (LCC 2015, BCC 2005). Gossia gonoclada (angle-stemmed myrtle) Conservation Advice Page 3 of 5 Survey and Monitoring priorities • Continue to undertake surveys in suitable and potential habitat to locate any additional populations. • Design and implement a monitoring program to monitor progress of recovery, including the effectiveness of management