This Conservation Advice was approved by the Minister / Delegate of the Minister on: 3/07/2008. Approved Conservation Advice (s266B of the Environment Protection and Biodiversity Conservation Act 1999) Approved Conservation Advice for Acacia araneosa (Spidery Wattle)
This Conservation Advice has been developed based on the best available information at the time this conservation advice was approved.
Description Acacia araneosa, Family Mimosaceae, also known as Spidery Wattle and Balcanoona Wattle, is a small, erect, wispy tree, 3–8 m high with minute, yellow, globular flower heads (Whibley & Symon, 1992). Flowers are borne irregularly throughout the year (Leigh et al., 1984; Whibley & Dashorst, 1985; Jessop & Toelken, 1986; Whibley & Symon, 1992). Fruiting occurs in October and November (Whibley, 1976). Conservation Status Spidery Wattle is listed as vulnerable. This species is eligible for listing as vulnerable under the Environment Protection and Biodiversity Conservation Act 1999 (Cwlth) (EPBC Act) as, prior to the commencement of the EPBC Act, it was listed as vulnerable under Schedule 1 of the Endangered Species Protection Act 1992 (Cwlth). The species is also listed as endangered under the National Parks and Wildlife Act 1972 (South Australia). Distribution and Habitat Spidery Wattle is restricted to a small area of northern Flinders Ranges in South Australia. It is confined to Vulkathunha–Gammon Ranges National Park and adjacent Arkaroola Sanctuary, with an 8 km2 area of occurrence and a population of approximately 1000 individuals (Davies, 1995). This species occurs within the South Australian Arid Lands Natural Resource Management Region. This species grows on calcareous soil on hillsides and ridges. It often occurs in dense stands within dry open woodland of Curly Mallee (Eucalyptus gillii) and Triodia irritans (Whibley, 1976; Whibley & Dashorst, 1985; Orchard & Wilson, 2001). The soil is a crusty alkaline neutral red duplex. The annual rainfall averages about 200 mm (Whibley & Symon, 1992). The distribution of this species is not known to overlap with any EPBC Act-listed threatened ecological community. Threats The main identified threats to Spidery Wattle are habitat degradation and browsing by feral rabbits (Oryctolagus cuniculus) and feral goats (Capra hircus) (Leigh et al., 1984; Davies, 1995), and introduced plant species (DEH SA, 2006). Browsing by goats is particularly severe in the south of Vulkathunha–Gammon Ranges National Park, near Munyallina Creek (Davies, 1995). Browsing by goats in Arkaroola Pastoral Lease was also noted (Davies, 1995). The main potential threats to Spidery Wattle include mining, as a mining exploration licence exists for the entire range of the species (Davies, 1995). Research Priorities Research priorities that would inform future regional and local priority actions include: • Design and implement a monitoring program that includes continued monitoring of permanent plant sites in Vulkathunha–Gammon Ranges National Park (Baulderstone et al., 1999). • More precisely assess population size, distribution, ecological requirements and the relative impacts of threatening processes. Acacia araneosa Conservation Advice - Page 1 of 3 This Conservation Advice was approved by the Minister / Delegate of the Minister on: 3/07/2008. • Undertake survey work in suitable habitat and potential habitat to locate any additional populations/occurrences/remnants. • Undertake seed germination and/or vegetative propagation trials to determine the requirements for successful establishment. Regional and Local Priority Actions The following priority recovery and threat abatement actions can be done to support the recovery of Spidery Wattle. Habitat Loss, Disturbance and Modification • Monitor known populations to identify key threats. • Monitor the progress of recovery, including the effectiveness of management actions and the need to adapt them if necessary. • Identify populations of high conservation priority. • Ensure maintenance or development activities in areas where Spidery Wattle occurs do not adversely impact on known populations. • Control access routes to suitably constrain public access to known sites on public land. • Suitably control and manage access on private land. • Manage any changes to hydrology that may result in changes to the water table levels, increased run-off, sedimentation or pollution. • Manage any disruptions to water flows. • Investigate formal conservation arrangements such as the use of covenants, conservation agreements or inclusion in reserve tenure. Invasive Weeds • Identify and remove weeds in the local area, which could become a threat to Spidery Wattle, using appropriate methods. • Manage sites to prevent introduction of invasive weeds, which could become a threat to Spidery Wattle, using appropriate methods. Trampling, Browsing or Grazing • Implement the management plans for the control and eradication of feral goats and rabbits in the local region. • Prevent grazing pressure at known sites on leased crown land through exclusion fencing or other barriers. Conservation Information • Raise awareness of Spidery Wattle within the local community and among relevant mining interests. Enable Recovery of Additional Sites and/or Populations • Undertake appropriate seed collection and storage. • Investigate options for linking, enhancing or establishing additional populations. • Implement national translocation protocols (Vallee et al., 2004) if establishing additional populations is considered necessary and feasible.
This list does not necessarily encompass all actions that may be of benefit to Spidery Wattle, but highlights those that are considered to be of highest priority at the time of preparing the conservation advice.
Existing Plans/Management Prescriptions that are Relevant to the Species • Threat Abatement Plan for Competition and Land Degradation by Feral Goats (EA, 1999a),
Acacia araneosa Conservation Advice - Page 2 of 3 This Conservation Advice was approved by the Minister / Delegate of the Minister on: 3/07/2008. • Threat Abatement Plan for Competition and Land Degradation by Feral Rabbits (EA, 1999b), and • Vulkathunha–Gammon Ranges National Park Management Plan (DEH SA, 2006). These prescriptions were current at the time of publishing; please refer to the relevant agency’s website for any updated versions.
Information Sources: Baulderstone, CS, Owens, H, Possingham, ML & Possingham, HP 1999, Gammon Ranges National Park: Flora and Fauna Survey, and Vegetation Monitoring, 1993-1995, Nature Conservation Society of South Australia Inc, Adelaide. Briggs, JD & Leigh JH 1996, Rare or Threatened Australian Plants, CSIRO Publishing, Collingwood. Davies, RJP 1995, Threatened Plant Species Management in National Parks and Wildlife Act Reserves in South Australia, Botanic Gardens of Adelaide, Athelstone. Department for Environment and Heritage (DEH) SA 2006, Vulkathunha-Gammon Ranges National Park Management Plan, viewed 30 March 2008,
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