Category Archives: Western Australia

Seagrass rehabilitation and restoration, Cockburn Sound, WA

Key words. Coastal ecosystems, transplanting trials, compensatory restoration, Posidonia

Introduction. Seagrasses are flowering plants that form extensive underwater meadows, transforming bare sandy areas into complex 3-dimensional habitats for a diverse faunal community. They provide a wide range of ecosystem services including nutrient cycling, carbon sequestration, and coastal stabilization. Once impacted, seagrass meadows can take decades to recover.

The need for seagrass restoration is mainly driven by loss of seagrass due to human activities including ocean discharges and coastal developments, although changing ocean conditions (warming temperatures and increasing acidity) and sea-level rise now provide additional challenges.

 Posidonia australis, from planting unit to spreading and merging shoots.

Figure 1. Posidonia australis showing spreading and merging shoots from what were initially only single planting units (see inset).

Cockburn Sound project. In 2003, the Seagrass Research and Rehabilitation Plan (SRRP) was established to meet stringent environmental management conditions for two separate industrial development projects in Cockburn Sound, Western Australia. Both projects, Cockburn Cement Ltd and the state Department of Commerce, impacted upon seagrass ecosystems.

The SRRP was aimed at developing and implementing seagrass restoration procedures that are economically feasible and environmentally sustainable. The collaborative project team was coordinated by BMT Oceanica and included researchers from Murdoch University, The University of Western Australia, Edith Cowan University, the Botanic Gardens and Parks Authority, environmental consultants and a marine engineering firm.

Works and their results. Implementing the SRRP involved a range of experimental transplantings of the seagrass Posidonia australis (a slow-growing meadow-forming species).

The transplant trials resulted in good health and high survival rates of transplanted shoots. This showed that meadows can be restored and thus are likely to develop and return to the same ecological functions as natural meadows.

In this case, donor material was harvested from a site that was to be destroyed as part of the permitted development. In other cases, donor material has been harvested from meadows that have demonstrated varying levels of recovery, with a number of years required for recovery depending on the intensity of harvesting. The project resulted in site-specific solutions as well as generic technical guidelines for manual transplantation to restoration sites from donor sites.

Lessons and limitations. The main lessons for practice to date are:

  • While the results of this project are encouraging, the challenge of achieving biological diversity in seagrass meadows, particularly to the equivalence of a natural seagrass meadow, has not yet been demonstrated.
  • The scale of this particular project is still small (3.2 Ha) relative to the amount of restoration required. Focus needs to be on research into how such projects can be scaled-up. Seed-based restoration may be more appropriate for some species (including Posidonia).
  • Selection of a restoration site is a strong factor contributing to the success of transplanted material (i.e. the likelihood of success if higher where seagrass was present before).

Contact. Dr Jennifer Verduin, lecturer, Murdoch University , Tel: +61 8 93606412/0404489385; Email:

Also see:

EMR project summary – report on the seagrass transplanting trials:

Full EMR feature article


Project Eden: Fauna reintroductions, Francois Peron National Park, Western Australia

Per Christensen, Colleen Sims and Bruce G. Ward

Key words. Ecological restoration, pest fauna control, captive breeding, foxes, cats.

Figure 1. The Peron Peninsula divides the two major bays of the Shark Bay World Heritage Area, Western Australia.

Figure 1. The Peron Peninsula divides the two major bays of the Shark Bay World Heritage Area, Western Australia.

Introduction. In 1801, 23 species of native mammals were present in what is now Francois Peron National Park. By 1990 fewer than half that number remained (Fig 1.). Predation by introduced foxes and cats, habitat destruction by stock and rabbits had driven many native animals to local extinction.

Project Eden was a bold conservation project launched by the WA government’s Department of Conservation and Land Management (CALM -now Dept of Parks and Wildlife) that aimed to reverse extinction and ecological destruction in the Shark Bay World Heritage Area.

The site and program. Works commenced in Peron Peninsula – an approx. 80 km long and 20 km wide peninsula on the semi-arid mid-west coast of Western Australia (25° 50′S 113°33′E) (Fig 1). In the early 1990s, removal of pest animals commenced with the removal of sheep, cattle and goats and continued with the control of feral predators. A fence was erected across the 3km ‘bottleneck’ at the bottom of the peninsula where it joins the rest of Australia (Fig 2) to create an area where pest predators were reduced to very low numbers.

Figure 2. The feral proof fence was erected at the narrow point where Peron Peninsula joins the mainland.

Figure 2. The feral proof fence was erected at the narrow point where Peron Peninsula joins the mainland.

Once European Red Fox (Vulpes vulpes) (estimated at 2500 animals) was controlled and feral Cat (Felis catus) reduced to about 1 cat per 100 km of monitored track, sequential reintroductions of five locally extinct native animals were undertaken (Figs 3 and 4).  These included: Woylie (Bettongia penicillata – first introduced in 1997), Malleefowl (Leipoa ocellata – 1997), Bilby (Macrotis lagotis – 2000), Rufous Hare-wallaby (Lagorchestes hirsutus – 2001), Banded Hare-wallaby (Lagostrophus fasciatus -2001), Southern Brown Bandicoot (Isoodon obesulus – 2006) and Chuditch (Dasyurus geoffroi geoffroi -2011?)

Methods. Cat baiting involved Eradicat® cat baits, which were applied annually during March–April at a density of 10 to 50 baits/km2. Cat baiting continued for over 10 years, supplemented with a trapping program, carried out year round over a 8 -year period. Cat trapping involved rolling 10 day sessions of leghold trapping along all track systems within the area, using Victor Softcatch No. 3 traps and a variety of lures (predominantly olfactory and auditory).Tens of thousands of trap nights resulted in the trapping of up to 3456 animals. Fox baiting involved dispersal of dried meat baits containing 1080 poison by hand or dropped from aircraft across the whole peninsula. Baiting of the peninsula continues to occur annually, and removes any new foxes that may migrate into the protected area and is likely to regularly impact young inexperienced cats in the population, with occasional significant reductions in the mature cat population when environmental conditions are favourable.

Malleefowl were raised at the Peron Captive Breeding Centre from eggs collected from active mounds in the midwest of Western Australia. Woylies were reintroduced from animals caught in the wild from sites in the southwest of Western Australia, with Bilbies sourced from the Peron Captive Breeding Centre, established by CALM in 1996 to provide sufficient animals for the reintroductions. The centre has since bred more than 300 animals from five species

Monitoring for native mammals involved radio-tracking of Bilbies, Woylies, Banded Hare Wallabies, Rufous Hare-Wallabies, Southern Brown Bandicoots, Chuditch and Malleefowl at release, cage trapping with medium Sheffield cage traps and medium Eliots, as well as pitfall trapping of small mammals. The survey method for cats utilized a passive track count survey technique along an 80 km transect through the long axis of the peninsula. The gut contents of all trapped cats were examined.

Fig. 3. Woylies were first introduced in 1997 from animals caught in the wild at sites in southwest Western Australia.

Figure 3. Once foxes were controlled and cats reduced to about 1 cat per 100 km of monitored track, sequential reintroductions of five locally extinct native animals were undertaken. Woylies were first introduced in 1997 from animals caught in the wild at sites in southwest Western Australia.

Once European Red Fox (Vulpes vulpes) (estimated at 2500 animals) was controlled and feral Cat (Felis catus) reduced to about 1 cat per 100 km of monitored track, sequential reintroductions of five locally extinct native animals were undertaken.

Figure 4. Tail tag being fitted to a Bilby. (Bilbies were re-introduced to the Peron Peninsula in 2000, from animals bred in the Peron Captive Breeding Centre.)

Results. Monitoring has shown that two of the reintroduced species – the Malleefowl and Bilby – have now been successfully established. These species are still quite rare but they have been breeding on the peninsula for several years The Woylie population may still be present in very low numbers, but despite initial success and recruitment for six or seven years, has gradually declined due to prolonged drought and low level predation on a small population. Although the released Rufous Hare-wallabies and the Banded Hare-wallabies survived for 10 months and were surviving and breeding well, they disappeared because of a high susceptibility to cat predation and other natural predators like wedge-tailed eagles. Although some predation of Southern Brown Bandicoot has occurred and the reintroduction is still in the early stages, this species has been breeding and persisting and it is hoped that they will establish themselves in the thicker scrub of the peninsula.

Lessons learned. We found that the susceptibility to predation by cats and foxes varies considerably between species. Malleefowl are very susceptible to fox predation because the foxes will find their mound nests, dig up their eggs up and eat them – consequently wiping them out over a period of time. As cats can’t dig, Malleefowl can actually exist with a fairly high level of cats. Bilbies live in their burrows and are very alert so they can persist despite a certain level of cats. But the Rufous Hare-wallaby and the Banded Hare-wallaby are very susceptible to cat predation and fox predation due to their size and habits.

Examination of the period of time when species disappeared from the Australian mainland showed that there was a sequence of extirpations, reflecting the degree to which the species were vulnerable to pest predators. The ones that survived longest are those that are less vulnerable. This suggests that if complete control of predators is not possible (considering cat control is extremely difficult), it is preferable to focus on those animals that are least vulnerable. While it could be argued that reintroductions should be delayed until such time as all the cats and foxes have been removed, such a delay (which might take us 10, 20 or even 100 years) is likely to exceed the period of time many of these species will survive without some sort of assistance. It is likely to be preferable to proceed with reintroductions although we might be losing some animals.

Future directions. As with the majority of mainland reintroduction projects, level of predator control is the key to successful establishment of reintroduced fauna. The Project is currently under a maintenance strategy and future releases, which included the Western Barred Bandicoot (Perameles bougainville), Shark Bay Mouse (Pseudomys fieldi), geoffroi), Greater Stick-nest Rat (Leporillus conditor) and Red-tailed Phascogale (Phascogale calura) are on hold until improved cat control techniques are available. Despite the uncertain future for reintroductions of these smaller species, ongoing feral animal control activities and previous reintroductions have resulted in improved conditions and recovery for remnant small native vertebrates (including thick billed grass wrens, woma pythons and native mice), and new populations of several of the area’s threatened species which are once again flourishing in their original habitats.

Acknowledgements: the program was carried out by Western Australia’s Department of Parks and Wildlife and we thank the many Departmental employees, including District and Regional officers for their assistance over the years, and the many, many other people that have volunteered their time and been a part of the Project over the years, for which we are very grateful.

Contact: Colleen Sims, Research Scientist, Department of Parks and Wildlife (Science and Conservation Division, Wildlife Research, Wildlife Place, Woodvale, WA 6026, Australia, Tel: +61 8 94055100; Email: Also visit:

Further detail and other work in WA:

Per E. S. Christensen, Bruce G. Ward and Colleen Sims (2013) Predicting bait uptake by feral cats, Felis catus, in semi-arid environments. Ecological Management & Restoration 14:1, 47-53.

Per Christensen and Tein McDonald (2013) Reintroductions and controlling feral predators: Interview with Per Christensen. Ecological Management & Restoration, 14:2 93–100.


Peniup Ecological Restoration Project

Justin Jonson

Key words: reconstruction, planning, direct seeding, monitoring, innovation

Introduction. The Peniup Restoration Project was initiated in 2007, when Greening Australia and Bush Heritage Australia jointly purchased a 2,406 hectare property as a contribution to the conservation and restoration objectives of Gondwana Link. The property has an average annual rainfall of approximately 450mm per year and had previously been farmed in a traditional broad acre sheep and cropping rotation system. The site is located within a highly diverse mosaic of varying soils and associated vegetation associations across Mallee, Mallee Shrubland, and Woodland type plant communities.

Planning and 2008 Operational Implementation. In 2008, Greening Australia’s Restoration Manager Justin Jonson developed a detailed ecological restoration plan for 950 hectares of cleared land on the northern section of the property. Information and procedures applied for that work are detailed in the EMR Journal article Ecological restoration of cleared agricultural land in Gondwana Link: lifting the bar at ‘Peniup’ (Jonson 2010). Further information is also available for the specific vegetation associations established via the Peniup Restoration Plan, with species lists according to height stratum, including seedlings planted by hand which were nitrogen fixing or from the Proteaceous genera. Funding for the initial 250 hectares of restoration were raised and the project implemented in 2008 (Fig.1).

Figure 1. Map showing the 2008 operational areas at Peniup with replanted communities replanted by direct seeding, and GPS locations of permanent monitoring plots (n=42), patches of hand planted seedlings (n=31) and seed (n=61), pre-planning soil sampling sites (n=115) and contour oriented tree belts to ensure establishment across the site (direct seeded understory consistently here).

Figure 1. The 2008 operational areas at Peniup showing communities replanted by direct seeding, and GPS locations of permanent monitoring plots (n=42), patches of hand planted seedlings (n=31) and seed (n=61), pre-planning soil sampling sites (n=115) and contour oriented tree belts to ensure establishment across the site.

Figure 2: Map showing GPS locations of permanent monitoring plots established at Peniup.

Figure 2. Location of 42 Permanent Monitoring Plots established in 2008 Peniup Ecological Restoration Project. Recruits from the direct seeding were measured 5 months after implementation, and then annually to assess persistence and long term development

Monitoring. A total of 42 monitoring plots were laid out across seven of the nine plant communities established (Fig.2). Details of the methodology, results and ongoing evaluation have been published (Jonson 2010; Hallet et al. 2014; Perring et al. 2015).

Results to date.  Monitoring indicates approximately 3.8 million plants were re-established by the direct seeding across the 250 hectare project area.  The numbers established in each plant community are shown in Fig.3 and represent the majority of plant species in each reference model. After 8 years it is clear that the project’s objectives are on track to being achieved, considering: a) absence of agricultural weeds; b) nutrient cycling through build up and decomposition of litter and other detritus;  seed-rain by short-lived nitrogen-fixing Acacia shrubs, c) diverse structural development of re-establishing species; and,  d) presence of many target animals using the site. Peniup’s progress in terms of recovery of the National Restoration Standards’s 6 ecosystem attributes is depicted and tablulated in Appendix 1.

Figure 3: Chart showing per hectare estimates of plant establishment counts by restoration plant community.

Figure 3. Per hectare estimates of Peniup plant establishment counts by restoration plant community.

Figure 4. Photo of riparian/drainage Tall Yate open woodland community with mid and understory shrubs and mid-story trees.

Figure 4. Riparian/drainage Tall Yate open woodland community at Peniup – with mid and understory shrubs and mid-story trees.

Innovation. As an adaptive management approach, small, discrete patches of seedlings of the proteaceous family were hand planted to make best use of small quantities of seed. Planting of these 5,800 seedlings in small patches, termed ‘Nodes’, provided further resource heterogeneity within relatively uniform seed mixes (by soil type). The impetus for this approach was to create concentrated food sources for nectarivorous fauna, while increasing pollination and long-term plant species viability (Jonson 2010).

Figure 5. Map showing distribution of Proteaceous Nodes.

Figure 5. Distribution of Proteaceous Nodes.

Lessons learned. Continuity of operational management is a critical component to achieving best practice ecological restoration. Project managers must be involved to some degree in all aspects of works, because flow on consequences of decisions can have high impact on outcomes. Detailed planning is also needed with large scale projects; otherwise the likelihood of capturing a large percent of site specific information is low. Finally, the use of GIS software for information management and site design is an absolute necessity.

Figure 6. Photo showing Banksia media and Hakea corymbosa plants with seed set.

Figure 6. Banksia media and Hakea corymbosa plants with seed set after 5 years.

Figure 7. hoto showing bird nest built within re-establishing Yate tree at Peniup within 5 years.

Figure 7. Bird nest within 5-year old Yate tree at Peniup.

Figure 8. Photo showing ecological processes in development including, a) absence of agricultural weeds, b) nutrient cycling and seed-rain deposition by short-lived nitrogen-fixing Acacia shrubs, c) diverse structural development of re-establishing species, and d) development of leaf litter and associated detritus for additional nutrient cycling.

Figure 8.  Five-year-old vegetation is contributing to a visible build up of organic matter and decomposition is indicating cycling of nutrients.

Stakeholders and Funding bodies. Funding for this Greening Australia restoration project was provided by The Nature Conservancy, a carbon offset investment by Mirrabella light bulb company, and other government and private contributions.

Contact information. Justin Jonson, Managing Director, Threshold Environmental, PO Box 1124, Albany WA 6330 Australia, Tel:  +61 427 190 465;

See also EMR summary Monjebup

Watch video: Justin Jonson 2014 AABR presentation on Peniup

Appendix 1. Self-evaluation of recovery level at Peniup in 2016, using templates from the 5-star system (National Standards for the Practice of Ecological Restoration in Australia)

Fig 9. Peniup recovery wheel template

Evaluation table2

Defining reference communities for ecological restoration of Monjebup North Reserve in Gondwana Link

Justin Jonson

Key words: reconstruction; reference ecosystem; planning; ecosystem assemblage; monitoring

Introduction. Bush Heritage Australia’s (BHA) Monjebup North Reserve is a property that directly contributes to the conservation, restoration and connectivity objectives of Gondwana Link – one of Australia’s leading landscape scale restoration initiatives. Building on a solid history of revegetation projects implemented by collaborators from Greening Australia and individual practioners, the BHA management team initiated and funded a $40K Ecological Restoration Planning Project for 400 hectares of marginal farmland in need of restoration.

The specific aim of the Monjebup North Ecological Restoration Project was to 1) plan and 2) implement a ‘five star’ ecological restoration project as defined by the Gondwana Link Restoration Standards. Overarching goals included the re-establishment of vegetation assemblages consistent with the surrounding mosaic of plant communities, with a specific focus on local fauna and the restoration of habitat conditions to support their populations.

Figure 1: Map showing GPS locations of soil auger sampling locations.

Figure 1: Map showing GPS locations of soil auger sampling locations.

Planning and identification of reference communities for restoration of cleared land. The Monjebup North Ecological Restoration Project began with a third party consultancy contract to develop the Monjebup North Ecological Restoration Plan. This work began with the collection of detailed field data, including 120 soil survey pits collected to define the extent and boundaries between different soil-landform units occurring on the site (Fig.1). In the absence of previously defined and/or published information on local plant communities, an additional vegetation survey and report, The Vegetation of Monjebup North, was developed, which included 36 vegetation survey sites widely distributed across the surrounding vegetation (Fig.2). A total of 10 primary vegetation associations were defined within remnant vegetation on and around the site from this work (Fig.3). Additional soil survey pits were established within these defined plant communities to develop relationships between observed vegetation associations and soil-landform units. Cross referencing this information to the 400 hectare area of cleared land resulted in the delineation of seven core reference communities to guide the restoration project. These restoration communities ranged from Banksia media and Eucalyptus pluricaulis Mallee Scrub associations on spongelitic clay soils, to Eucalyptus occidentalis (Yate) Swamp Woodland associations located in low-lying areas where perched ephemeral swamps exist.

Figure 2: Map showing GPS locations of flora survey sampling sites.

Figure 2: Map showing GPS locations of flora survey sampling sites.

Figure 3: Output map of dominant vegetation associations at Monjebup North Reserve.

Figure 3: Output map of dominant vegetation associations at Monjebup North Reserve.

Figure 4: Mosaic of plant communities replanted at Monjebup North in 2012 using direct seeding and hand planted seedlings. A tractor fitted with GPS unit enables real time seeding passes, as shown on the map.

Figure 4: Mosaic of plant communities replanted at Monjebup North in 2012 using direct seeding and hand planted seedlings. A tractor fitted with GPS unit enables real time seeding passes, as shown on the map.

Figure 5: Mosaic of plant communities replanted at Monjebup North in 2013 using direct seeding and hand planted seedlings. A tractor fitted with GPS unit enables real time seeding passes, as shown on the map.

Figure 5: Mosaic of plant communities replanted at Monjebup North in 2013 using direct seeding and hand planted seedlings. A tractor fitted with GPS unit enables real time seeding passes, as shown on the map.

Seed sourcing. Seed from approximately 119 species were collected on and around the site for the restoration works. Seed collections for some species were collected from a number of geographically separate sub-populations, however these were never located further than 10 kilometers from site. Collections were made from at least 20 individuals for each species, and preference was made in collecting from populations which had 200+ individuals.

The primary on-ground works were initiated across four years from 2012 to 2015, starting with a 100 ha project area in 2012 (Fig.4), and a 140 ha area in the following year (Fig.5), both by Threshold Environmental Pty Ltd. A combination of direct seeding and hand planted seedlings treatments were employed, where seed mixes were developed to achieve the bulk of plant recruitment across each of the soil-land form units, and nursery grown seedlings were planted by hand for species found to be difficult to establish from direct seeding or for which stocking densities were to be more closely controlled. This work involved 13 communities and 148 species.

A number of innovative operational treatments were employed. These included grading 5 kilometers of contour banks and spreading chipped vegetation and seed pods, and 180 in situ burning patches where branch and seed material from fire-responsive serotinous species were piled and burned (Fig.6 before, Fig.7 after). Seedlings for rare, high nectar producing plant species were also planted in 203 discrete ‘node’ configurations. Habitat debris piles made of on-site stone and large branch materials were also constructed at 16 locations across the 2012 project areas.

Fig.6 In situ burning of serotinous branch and seed material

Figure 7: Photo of Dryandra nervosa juvenile plants establishing from one of the in situ burn pile locations. Other species used for this technique included Dryandra cirsioides, Dryandra drummondii, Hakea pandanicarpa, Isopogon buxifolius, and Hakea corymbosa.

Figure 7: Photo of Dryandra nervosa juvenile plants establishing from one of the in situ burn pile locations. Other species used for this technique included Dryandra cirsioides, Dryandra drummondii, Hakea pandanicarpa, Isopogon buxifolius, and Hakea corymbosa.

Monitoring. Monitoring plots were established to evaluate the direct seeded revegetation, as presented in the Project Planting and Monitoring Report 2012-2013. Fauna monitoring has also been undertaken by BHA using pit fall traps, LFA soil records, and bird minute surveys.

Results to date. Monitoring collected from post establishment plots in from the 2012 and 2013 areas (2 years after seeding) showed initial establishment of 2.4 million trees and shrubs from the direct seeding (Fig.8 and Fig.9). Results of faunal monitoring are yet to be reported, but monitoring at the site for vegetation and faunal is ongoing.

Figure 8: Graphic representation of monitoring results from 2012 and 2013 operational programs showing scaled up plant counts across the plant community systems targeted for reconstruction.

Figure 8: Graphic representation of monitoring results from 2012 and 2013 operational programs showing scaled up plant counts across the plant community systems targeted for reconstruction.

Figure 9: Photo showing 3 year old establishment and growth of a Banksia media/Eucalyptus falcata Mallee shrub plant community with granitic soil influence from the 2012 Monjebup North restoration project.

Figure 9: Photo showing 3 year old establishment and growth of a Banksia media/Eucalyptus falcata Mallee shrub plant community with granitic soil influence from the 2012 Monjebup North restoration project.

Lessons learned and future directions. The decision to develop a restoration plan in advance of undertaking any on-ground works was a key component contributing to the success of the project to date. Sufficient lead time for contracted restoration practioners to prepare (>12 months) was also a key contributor to the success of the delivery. Direct collaboration with seed collectors with extensive local knowledge also greatly benefited project inputs and outcomes.

Stakeholders and Funding bodies. Major funding for the project was provided by Southcoast Natural Resource Management Inc., via the Federal Government’s National Landcare Program and the Biodiversity Fund. Of note is also Bush Heritage Australia’s significant investment in the initial purchase of the property, without which the project would not have been possible.

Contact information. Justin Jonson, Managing Director, Threshold Environmental, PO BOX 1124, ALBANY WA 6330 +61 427 190 465;

See also EMR summary Peniup

 Watch video: Justin Jonson 2014 AABR presentation

Nowanup: Healing country, healing people

Keith Bradby, Eugene Eades, Justin Jonson, Barry Heydenrych.

Key words: Noongar, Gondwana Link, cultural restoration, ecological restoration, design

Introduction. Greening Australia’s 754 ha Nowanup property was one of the first purchased with donor funds to help achieve the Gondwana Link programme’s goal of reconnecting native habitats across south-western Australia (Fig 1). The ecological work of Gondwana Link is underpinned by the involvement of people living within the region’s landscapes.

Nowanup (Fig 2) is a visually compelling place, with rising breakaway mesas, broad sweeping plains, and views south down the Corackerup valley and south west to the Stirling Range. Its remaining native vegetation systems are dominated by mallee shrublands, mallet and moort woodlands and banksia heathlands. It contains large populations of the locally endemic eucalypts Corackerup Moort (Eucalyptus vesiculosa) and Corackerup Mallet (E. melanophitra) and it is expected that additional rare flora species will be found. It also supports populations of a range of threatened fauna species including Malleefowl (Leipoa ocellata), Western Whipbird (Psophodes nigrogularis), Shy Groundwren (Hylacola cauta whitlocki), Crested Bellbird (Oreoica gutturalis gutturalis) and Black-gloved wallaby (Macropus irma). The original native vegetation remains in the upper section of the property (Fig 3), though much of this area has been cleared and burnt for farming, but never farmed. The farmland areas are now largely replanted.

Fig 1 Fitz-Stirling Corridor

Fig. 1. Nowanup is part of the broader Gondwana Link Program

Fig 2. Nowanup rock features

Fig. 2. Nowanup has visually compelling rock features and expansive landscapes.

Cultural significance. The groups involved in Gondwana Link support a range of social and cultural activities involving donors, farmers, government agencies, research bodies, industry groups and various landcare and natural resource management groups. Primary among these are the Aboriginal People, which for Nowanup is the local Noongar community.

Many Noongar elders knew the area well before it was cleared for farming, and speak of its cultural significance. Cultural mapping on the property has underlined that significance by locating a number of cultural sites and concentrations of artefacts. After purchase in 2004 the property was made available to the Noongar community, to support their aspirations, and Noongar leader Eugene Eades resides on Nowanup. Initially employed by Greening Australia as an Indigenous Engagement Officer, and now running camps and events at Nowanup as a Noongar led program, Eugene liaises with educational, corrections and welfare institutions and agencies to coordinate a range of educational and rehabilitation programmes. Eugene has also managed, with a team of young Noongar men, construction of a ‘Meeting Place’ that has assumed considerable significance for the local Noongar community (Fig 4).

Located in the heart of the Fitz-Stirling section of Gondwana Link, with its striking scenic qualities, a powerful sense of place, basic building infrastructure, cultural ‘Meeting Place’, and resident Noongar manager, Nowanup has become the focus for educational and cultural activities and programmes in the Fitz-Stirling, including an increasing level of Noongar involvement in the restoration plantings. These have included planting seedlings during community days and the expert planting of thousands of seedlings by four Noongar boys undertaking an eight week justice diversion program under Eugene Eades.

Fig 3 Nowanup aerial 2014. Courtesy Airpix

Fig. 3. The upper section of the property contains remnant or regrowth native vegetation, with the rest actively farmed prior to the revegetation

Approximately 340ha of the northern portion of the property is remnant bushland, with approximately 350 hectares of cleared land to the south, which has now been largely revegetated, including with trials of local species with commercial potential.

Some of the earlier plantings reflected a low-diversity revegetation approach, which was later improved across Gondwana Link plantings to better reflect the goal of ecological restoration modelled on local reference sites (see Monjebup summary). Nowanup’s early revegetation efforts were also impacted by difficulties in achieving good germination of a number of species on the sites difficult clay soils, with the result that many areas are dominated by a few species of eucalypts and acacias. These have been enriched recently by in-fill plantings which also demonstrate an improvement in the standard of work over 10 years. This has included improvements in the agronomy of direct seeding techniques (by Geoff Woodall), such as using direct drilling instead of scalping, that Greening Australia undertook in 2014, and which has subsequently been more widely used. In addition, integration of cultural and ecological aspects was advanced through a 2015 direct seeding project collaboratively designed by Eugene Eades and restoration practitioner Justin Jonson, which integrates indigenous cultural meaning and values into an ecological restoration project (Fig 4). The planting is only a year old, but the integration of cultural values and the sites biophysical conditions into one inclusive design is a powerful and innovative step forward. The site has been coined ‘Karta-Wongkin-Jini’ by Mr. Eades, which means ‘place where people come together’, and , with fantastic germination to date, is on track to serve as an important demonstration of culturally informed ecological restoration in practice.

Fig 4. Cultural EcoRestoration Systems 2015

Fig. 4. Eco-restoration design by Eugene Eades and Justin Jonson

Fig5. Cultural presentation Nowanup

Fig. 5. Schoolchildren enjoying a cultural presentation at the ‘Meeting Place’

Healing nature, healing people. Greening Australia was committed from the outset to engagement of the Noongar community in its operation in the Fitz-Stirling section of Gondwana Link. A cultural benefit of the project that was largely unforeseen but which developed rapidly has been the realization of the opportunities Nowanup presents for a range of programmes that support young Noongars at risk, as well as for rehabilitation and respite care. Eugene Eades has already supervised several Court arranged and respite care programmes on the property, and there is intense interest from a wide range of organisations in utilizing Eugene and Nowanup for running an extended range of programmes in the future (Fig 5). A project focused on the healing of country has great potential also for healing people.

The running of such programmes is out of scope for a conservation NGO whose mission is the transformation of landscape at scale. The programmes to date have made do with the very basic infrastructure that currently exists on Nowanup, with Greening plus supporters and donors subsidizing Eugene’s role in managing the programmes. Even while operating on this ad hoc basis, the programmes have proved Nowanup’s enormous potential for expanded cultural and social endeavours in the future. Greening Australia is keen to contribute to a transition that will allow for Nowanup’s full potential for such purposes to be realized.

Fig 6. Noongar planters by Ron D'Raine

Fig 6. Elder Aden Eades, Eugene Eades and Bill Woods lead a community planting day on Nowanup

Issues and Options. The framework plantings and larger scale direct seeding on Nowanup is now essentially complete, with the last significant works having been undertaken in 2015 – although infill plantings and seeding will occur as funding allows (Fig 6). From this point on, continuing conservation management of the property is required to ensure its contribution to ecological health in the Fitz-Stirling increases as the restoration work matures. With Greening Australia’s key focus on ecological restoration, there is no reason why properties that have been restored should not be subsequently divested to alternative ownership, so long as the necessary conservation covenants and management arrangements are in place. With Nowanup this would ideally be a body representative of local Noongar community interests. With both the original habitat areas and the revegetation and restoration areas already under protective covenant, the agreements and arrangements can be put in place to provide certainty for investment by corrections and/or welfare agencies into the infrastructure required to run properly-resourced programmes on the property. Nowanup will then be better placed to realize its full potential in healing country and people.

Funding: Revegetation costs were largely met through the Reconnections program, funded by Shell Australia, the Commonwealth Government’s Biodiversity Fund and 20 Million Trees Programme. Eugene Eades funds the cultural and social programs as a private business. Gondwana Link Ltd and Greening Australia provide support as needed.

Contact: Keith Bradby, Gondwana Link. PO Box 5276, Albany WA 6332. Phone: +61 (0)8 9842 0002. Email:

Read also EMR project summaries:


Post-sand extraction restoration of Banksia woodlands, Swan Coastal Plain, Western Australia.

Deanna Rokich

Key words: research-practice partnership, adaptive management, smoke technology, cryptic soil impedance, topsoil handling.

Figure 1. Examples of undisturbed Banksia woodland reference sites.

Introduction. Banksia woodlands were once a common and widespread feature of the Swan Coastal Plain, Western Australia (Fig. 1); today less than 35% of the original Banksia woodlands remain in metropolitan Perth. When sand extraction activities were permitted over 25 years ago, Hanson Construction Materials opted to go well beyond the statutory minimum requirement of re-instating local native species. Instead, Hanson committed to meet the challenge to return post-sand extracted sites (Fig. 2) to an ecosystem closely resembling the pre-disturbance Banksia woodland. To achieve this high resemblance to the reference ecosystem, Hanson operations sought the assistance of the Science Directorate team within the Botanic Gardens and Parks Authority in 1995. BGPA developed and implemented a research and adaptive management program with Hanson, resulting in a collaboration involving graduate and post-graduate student research programs into key facets of Banksia woodland ecosystem restoration, application of outcomes into restoration operations, and finally, restoration sites that are beginning to mimic reference sites (Fig.3).

Prior to the partnership, species richness and plant abundance, and thus restoration success, was limited in the rehabilitation. Research and adaptive management subsequently focused on improvements in soil reconstruction; topsoil management; seed germination enhancement (including smoke technology); seed broadcasting technology and whole-of-site weed management.

Monitoring. BGPA scientists have been undertaking annual plant monitoring of Banksia woodland restoration activities within reference and restoration sites for ca 15 years. This has resulted in data-sets on seedling emergence and plant survival within a range of sites, culminating in the development of annual performance criteria and ultimately, the ability to measure restoration performance in the short (e.g. from seedling emergence) and long-term (e.g. from plant survival).


Figure 2. The greatly reduced Banksia woodland sand profile following sand extraction, with topsoil being spread onto the pit floor.

Results. Consolidation of ca 15 years of data from >50 sites (encompassing a range of topsoil quality and climatic conditions) has revealed that stem density and species richness fall into three levels of restoration:

  • good restoration quality (high topsoil quality and favourable climatic conditions).
  • medium restoration quality (poor topsoil quality or unfavourable climatic conditions).
  • poor restoration quality (poor topsoil quality and unfavourable climatic conditions).

The integration of key research areas has resulted in:

  • Identification of first year species re-instatement being the blueprint for long-term species re-instatement.
  • Observation of cryptic soil impedance and extremely high plant loss in the standard ‘topsoil over overburden’ profile during the 2nd summer following restoration, but higher plant re-instatement and better ecosystem dynamics in the long term.
  • Improvement in seedling re-instatement, illustrated by perennial species return increasing from less than 10% to more than 70% (i.e. >100 perennial species), and stem density return of >140 perennial plants per 5m2 in Year 1, primarily due to improved topsoil handling methods – i.e. good quality, fresh and dry topsoil.
  • A ten-fold increase in the stem density of seedlings derived from direct-seeding due to innovative seed coating technology, delivery to site technology and sowing time optimisation.
  • Trebling of seedling recruitment success due to application of smoke technology.
  • Minimised weed invasion through the use of good quality and fresh topsoil, burial of the weed seedbank and prompt active weed management.

Figure 3. Restoration sites after 8 years, illustrating the return of the Banksia trees.

Implications for other sites. The post-sand extraction sites have provided important lessons and information about the management and restoration needs of Banksia woodlands – e.g. a high level of intervention is necessary, whilst cross-application of general restoration principles are not always possible for Banksia woodlands – useful for all those involved with managing and restoring Banksia woodland fragments within the broader Perth region.

Current and future directions. Hanson is committed to ongoing improvement through research – continually testing and employing new research techniques, programs and equipment that are recommended from BGPA research programs.

Post-sand extraction restoration practices now involve:

  • re-instating the soil profile in its natural order of topsoil over overburden, in spite of the cryptic soil impedance witnessed in the overburden in the 2nd summer following restoration;
  • striving for highest seedling establishment in the first year of restoration, prior to onset of soil impedance;
  • stripping and spreading only good quality (free of weeds), fresh and dry topsoil;
  • conserving topsoil by a strip:spread ratio of 1:2 (i.e. stripping over 1ha and spreading over 2ha);
  • burying direct-sown seeds given that seed displacement from wind and invertebrate activity is prolific during the typical seed sowing season; and
  • ceasing the common practices of mulching sites and tree-guarding plants as they provide negative or no benefits.

The partners are considering re-doing sites rehabilitated during 1991-1994, prior to research, in order to improve species diversity.

Acknowlegments: Botanic Gardens and Parks Authority and Hanson Construction Materials are the key parties in this project; involving many individual managers, researchers and students.

Contact: Deanna Rokich –

Plant communities of seasonal clay-based wetlands of south-west Australia: weeds, fire and regeneration

Kate Brown and Grazyna Paczkowska

Key words: regeneration, fire, seasonal wetlands

 While the majority of seasonal wetlands in south-west Australia are connected to regional ground water, some found on clay substrates rely solely on rainwater to fill. These seasonal clay-based wetlands fill with winter rains and are characterised by temporally overlapping suites of annual and perennial herbs that flower and set seed as the wetlands dry through spring. Over summer the clay substrates dry to impervious pans. The seasonal clay-based wetlands of south-west Australia comprise a flora of over 600 species, of which at least 50% are annual or perennial herbs, 16 occur only on the clay-pans and many are rare or restricted.

These ecological communities are amongst the most threatened in Western Australia and have recently been listed under the Commonwealth Environmental Protection and Biodiversity Conservation Act as critically endangered. Over 90% have been cleared for agriculture and urban development and weed invasion is a major threat to those that remain. South African geophytes are serious weeds within these communities and Watsonia (Watsonia meriana var. bulbillifera) in particular can form dense monocultures and displace the herbaceous understorey.

Watsonia invading  a seasonal clay-based wetland

Watsonia invading a seasonal clay-based wetland

Regeneration following weed control and fire.  We investigated the capacity of the plant community of such a wetland to regenerate following removal of Watsonia, and the role of fire in the restoration process.

 Our study site, Meelon Nature Reserve, is a remnant clay-based wetland on the eastern side of the Swan Coastal Plain 200 km south of Perth. A series of transects were established in August 2005 and regeneration of plant community following Watsonia control and then unplanned fire was monitored until September 2011 (Table 1).

 Table 1: Six years of monitoring regeneration of a seasonal wetland at Meelon Nature Reserve

August 2005 Thirty 1m x 1m  quadrats established along five 30m transects in the wetlands where Watsonia was estimated to average greater that 75% cover.
September 2005 Cover ( modified Braun Blaquet) recorded for all native and introduced taxa and then Watsonia treated with the herbicide 2-2DPA (10g/L) + the penentrant Pulse® (2.5 mL/L).
September 2006 Cover recorded for all native and introduced taxa and then Watsonia treatment reapplied.
February 2007 Unplanned wild fire burnt across the study site.
September 2007  each year until September 2011 Cover recorded for all native and introduced taxa and then any Watsonia treated.

Analysis of similarity (ANOSIM) was undertaken to determine if there was significant change in species cover and composition from before Watsonia control to six years following the initial treatment. A  SIMPER analysis was used to ascertain the contribution of each species to any changes between monitoring years (Clarke & Gorley 2006).

Results. In the first year of the control program, a 97% reduction in the cover of Watsonia was recorded, but was associated with no significant change in the diversity or abundance of native flora. In February 2007, 18 months after the initial control program, an unplanned summer wildfire burnt through the reserve. In September 2007 monitoring revealed a significant increase in cover and diversity of native species in the treatment areas. Some species such as the Dichopogon preissii had not been recorded before the fire, others, such as the native sedges, Cyathochaeta avenacea and Chorizandra enodis increased greatly in cover following the fire. At the same time there was no resprouting of Watsonia or recruitment from cormels or seed.

Six years after the initial treatment the native sedges and rushes continue to increase in cover, the dominant native shrub Viminaria juncea is increasing, Eucalyptus wandoo seedlings are recruiting into the site and native grasses and geophytes are increasing in cover. The indications are that plant communities of the seasonal clay-based wetlands of south-west Australia have the capacity to recover following major weed invasion and that fire can play a role in the restoration process.

Table 2. Species that contributed to 90% of the significant change in cover and composition of species between 2005 and 2011.





Average abundance (% cover)

Average abundance (% cover)

Cyathochaeta avenacea



Chorizandra enodis



Viminaria juncea



Caesia micrantha



Briza sp. Meelon



Eucalyptus wandoo



Austrodanthonia acerosa



Hypoxis occidentalis



Lepidosperma sp. WT2Q5 Meelon



Meeboldina sp. MU3 Meelon 2011



Dichopogon preissii



Drosera rosulata



Contact: Kate Brown, Ecologist, Swan Region. Department of Environment and Conservation, PO Box, 1167 Bentley Delivery Centre, WA, 6983. Email:

Chorizandra enodis

Chorizandra enodis

Dichopogon preissii

Dichopogon preissii

Hypoxis occidentalis

Hypoxis occidentalis

Restoration of Tuart (Eucalyptus gomphocephala) during prescribed burning in southwestern Australia

Katinka Ruthrof, Leonie Valentine and Kate Brown

Key words:  fire, regeneration, coarse woody debris, ashbed

Regeneration of Tuart (Eucalyptus gomphocephala), in many parts of its fragmented distribution in Western Australia, is nominal. Previous work has shown it has specific regeneration niche requirements, recruiting in ashbeds within canopy gaps. We conducted a field trial to determine whether regeneration could be facilitated by creating coarse woody debris (CWD) piles that would become ashbeds during a low-intensity, prescribed burn.

Regeneration experiment. Paganoni Swamp Bushland, a peri-urban Eucalyptus-Banksia woodland, was due for prescribed burning in 2011. Prior to the burn, twelve canopy gaps within the bushland were chosen to have CWD piles built up in the centre (5mx5m wide, 0.5m height). Six gaps were chosen to have no ashbeds, and so had any naturally occurring CDW removed. Adjacent to each plot (whether ashbed or no ashbed), an extra 5mx5m plot was marked out as a control.

The six gaps without ashbeds, and half of the 12 ashbeds, were broadcast with Tuart seed in plots of 5m x 5m following the prescribed burn.  Approximately 375 seeds/per 25m2 plot (after typical forestry seeding practice) were sown within one month of the prescribed burn.

The temperature of the control burn that moved through the area was measured in the gaps using pyrocrayons. These temperature-sensitive crayons were used to draw lines onto ceramic tiles. Five tiles were placed into each gap, either on the surface in the non-ashbed plots, or beneath the CWD piles, totaling 90 tiles.

Results. The majority of CDW piles burnt during the prescribed burning activities.  These piles burnt at high temperatures (~560Co) compared with the control plots (~70 Co). After six months, the ashbeds, especially those that were seeded, contained a significantly higher number of seedlings (0.7/m2 ± 0.3) than ashbeds without added seed (0.01/m2 ± 0.01) or control plots (0.0-0.05/m2 ± 0.0-0.05).

Lessons learned. Tuart regeneration can be facilitated at an operational scale as part of prescribed fire activities, through creation of CWD piles and broadcast seeding. However, higher rates of seeding could be used. Raking the seeds following broadcasting to reduce removal by seed predators may also increase seedling numbers.

Acknowledgements. Thanks go to the  State Centre of Excellence for Climate Change, Woodland and Forest Health, Murdoch University; Western Australian Department of Environment and Conservation; and to Friends of Paganoni Swamp.

Contact: Katinka Ruthrof, Research Associate, Murdoch University, South Street, Murdoch, 6150, Western Australia; Tel: (61-8) 9360 2605; Email:

A created coarse woody debris pile within a canopy gap, ready for the prescribed burn

A created coarse woody debris pile within a canopy gap, ready for the prescribed burn

A created ashbed following the prescribed burn

A created ashbed following the prescribed burn

Pyrocrayon markings on - a tile showing the temperature of the prescribed burn

Pyrocrayon markings on – a tile showing the temperature of the prescribed burn

Tuart seedlings recruiting following ashbed creation and broadcast seeding. Note that this is the same ashbed as in Figure 2.

Tuart seedlings recruiting following ashbed creation and broadcast seeding. Note that this is the same ashbed as in Figure 2.

Seagrass meadow restoration trial using transplants – Cockburn Sound, Western Australia

Jennifer Verduin and Elizabeth Sinclair

Keywords: marine restoration, seagrass, Posidonia australis, transplant, genetic diversity, microsatellite DNA, provenance

Cockburn Sound is a natural embayment approximately 16 km long and 7 km wide, to the west of the southern end of the Perth metropolitan area. Its seagrass meadows have been reduced in area by 77% since 1967, largely due to the effects of eutrophication, industrial development and sand mining. To answer a range of questions relevant to seagrass restoration, we (i) carried out a transplant trial, (ii) monitored the impact and recovery of the donor site, and (iii) retrospectively assessed genetic diversity in the transplant site.

Methods. (i) The transplant trial was conducted between 2004 and 2008 in an area totalling 3.2 hectares of bare sand at 2.2–4.0 m depth on Southern Flats, Cockburn Sound. Donor material was sourced from a naturally occurring seagrass meadow on Parmelia Bank, north of Cockburn Sound, approximately 16 km away from the transplant site. Sprigs (15–20 cm length) of a dominant local seagrass, Posidonia australis Hook.f., were harvested from donor material and each sprig tied to a purpose-designed degradable wire staples (30 cm in length) and planted and secured into a bare sandy area at 50 cm shoot spacing by SCUBA divers (Figure 1). Sprig survival was periodically monitored in 10 m x 10 m representative sub-plots (15–20 plots per hectare).

(ii) For the meadow recovery study, several plug (a clump of seagrass excavated) extraction configurations were examined in P. australis meadows to monitor shoot growth into plug scars, with metal rings placed into the resulting bare area to monitor shoot growth into it at 3, 10, 13 and 24 months. Rings of 8.3 cm diameter were placed into adjacent undisturbed meadows to act as reference plots. (iii) Shoot material was collected from established plants for microsatellite DNA genotyping from the donor site in 2004, and from the 2007/2008 plantings in the restoration site in January 2012. Genetic sampling from the restoration site was done from mature shoots only, to ensure we were sampling original donor material. DNA was extracted from shoot meristem and genotyped using seven polymorphic microsatellite DNA markers (Sinclair et al. 2009).


Figure 1. Transplants in situ, prior to the pegs being covering with sediment (Photo Jennifer Verduin)

Results. (i) The transplants have grown well to fill in gaps and become a healthy, self-sustaining meadow, with first flowering in July 2010, three years after initial transplant in 2007. There has also been considerable natural recruitment in the area through regrowth from matte and new seedlings (Figure 2). (ii) No significant differences in shoot growth between extraction configurations were observed in the donor meadow, and there was an increase in shoot numbers over two years. Based on the number of growing shoots, the predicted recovery time of a meadow is estimated at three years. (iii) Genetic diversity was very high in the restored meadow (clonal diversity R = 0.96), nearly identical to the donor meadow.


Figure 2. Aerial view of the restoration site (within yellow markers), with natural recruitment occurring from vegetative regrowth and new seedling recruits (Photo Jennifer Verduin, 2010).

Important considerations for long-term success and monitoring. While several important questions have arisen from this trial, it demonstrated that (i) the transplants achieved a high level of establishment within a few years; (ii) the high genetic diversity in the donor site was captured and retained in the restored meadow; and (iii) surrounding sandy substrate is being colonised by P. australis through regrowth from the matte and natural recruitment from seeds dispersed within and/or from other meadows, (the latter potentially helping to ensure the long-term viability of restored seagrass meadows.)

Partners and Investors: This project was carried out as part of the Seagrass Research and Rehabilitation Program through Oceanica Consulting Pty Ltd, with Industry Partners Cockburn Cement, Department of Commerce (formerly Department of Industry and Resources), WA, Department of Environment and Conservation WA, The University of Western Australia, and the Botanic Gardens and Parks Authority, WA.

Contact: Jennifer Verduin, School of Environmental Science, Murdoch University, Murdoch, WA 6150 Australia Email:; Elizabeth Sinclair, School of Plant Biology, University of Western Australia, Crawley, WA 6907 Australia Email: If you are interested in becoming involved with seagrass rehabilitation through student projects please contact us.



Bat recolonisation of restored jarrah forest in south-western Australia

Joanna Burgar

Keywords: Eucalyptus marginata, dry sclerophyll forest, fauna, echolocation, roost sites

The jarrah (Eucalyptus marginata) forest is part of the internationally recognised biodiversity hotspot of south-western Australia. The northern jarrah forest, approximately 700 000 ha, is subject to multiple uses including timber production, bauxite mining, water supply, recreation and conservation. Alcoa of Australia (hereafter Alcoa) clears, mines and restores approximately 600 ha of forest annually. Alcoa aims to restore a self-sustaining jarrah forest ecosystem. Research suggests that the floristic composition of the jarrah forest tends to be restored, but it is unknown whether the restored forest is habitat for the nine species of insectivorous bats that inhabit the region. Bats are generally considered resilient to human-induced disturbances because of their mobility, ability to exploit anthropogenic structures for roosting and their broad diet. This research project aims to determine if jarrah forest restored after bauxite mining provides habitat for bats.

Works undertaken: Bat activity was surveyed at 64 sites, restored forest of increasing age and reference (mature, unmined) forest (Fig 1), using passive echolocation call detectors. Each site was surveyed for eight nights in spring and summer over two consecutive years. During the first year of the survey, invertebrates were also surveyed at a subset of the sites (n = 24) to determine if there was a difference in invertebrate biomass between restored and reference sites. During the second year of the survey two species of bat, Southern Forest Bat (Vespadelus regulus) and Gould’s Long-eared Bat (Nyctophilus gouldi), were radio-tracked to their diurnal roosts to determine roost site preferences.

Results to date: Bat activity was extremely variable both within sites across nights of sampling and by restoration age. Despite this variation, overall bat activity was significantly higher in reference forest than in restored forest in either year of the survey. In restored forest, overall bat activity was relatively similar regardless of forest age. There was no difference in overall invertebrate biomass between restored and reference sites. The two bat species that were radio-tracked were never found roosting in restored forest. Rather, all diurnal roosts were located within the reference forest, largely in mature jarrah trees.


Figure 1. Restored jarrah forest of increasing age and reference (unmined) forest: a) 0-4 years post restoration; b) 5-9 years; c) 10-14 years; d) >15 years; and e) reference forest.

Lessons learned: Restored jarrah forest provides some habitat for bats, although bat activity was lower in restored than reference forest. Restored forest may provide foraging opportunities, as invertebrate biomass is similar in restored and unmined forest. However, tree hollows take decades to form, so roosting habitat is limited in the restored forest.

 Acknowledgements: This research was possible thanks to ARC Linkage Project LP0882687 between Murdoch University and Alcoa of Australia Limited.

Contact: Joanna Burgar, PhD Candidate, Murdoch University. Tel: +61 (0)8 9360 6520