Category Archives: Queensland

East Trinity remediation and rehabilitation after Acid Sulfate Soil contamination, north Queensland

Hanabeth Luke

Key words. Mangroves, estuarine habitat, migratory waders, ecological conversion

Introduction. The East Trinity case study describes the remediation of a severely degraded coastal acid sulfate soil site adjacent to the Cairns township in Queensland, Australia (Fig 1). The project involved extensive collaborative research into geochemistry, soil properties, groundwater and tidal behaviour, terrain modelling and flood modelling by a range of institutions. An innovative strategy known as lime-assisted tidal exchange (LATE) was used to reverse the acidification of the wetland, leading to improved water quality and health of coastal and estuarine ecosystems.

Acid sulfate soils are formed through a natural process that occurred when coastal lowlands were flooded in periods of high sea-level, leading to a slow build-up of metal sulfides such as pyrite. When these soils, normally protected by natural wetlands, are drained for farming or other development and exposed to oxygen, rapid oxidation of the pyrite occurred. This leads to a build-up of acidity in the soil as oxidation processes produce sulfuric acid, releasing toxic metals and noxious gases creating hostile conditions for plant growth. The acid also affects the availability of nutrients in the soil, creating another challenge for plant life. Rainfall events cause the acid, metals and nutrients to drain into waterways, impacting on aquatic ecosystems, infrastructure, fisheries and potentially, human health.

Figure 1. Aerial photo of he location of the East Trinity coastal and acid sulfate soil rehabilitation site (Source: Landsat 1999).

Figure 1. Aerial photo of he location of the East Trinity coastal and acid sulfate soil rehabilitation site (Source: Landsat 1999).

Prior condition and the degradation phase. East Trinity is a 940 ha coastal wetland situated between important estuarine habitats and a World Heritage listed wet tropical rainforest. Prior to clearing for farming, it was a mixture of paperbark woodland, tidal mangrove and salt marsh and had high ecological value for both marine and terrestrial faunal species. The area formed part of the traditional territory of the local Indigenous Mandingalbay Yidinji people.

The site was developed for sugar cane farming in the 1970s, with a bund-wall built to halt tidal inundation of the site. This drainage led to the oxidation of soil materials and a build-up of sulfuric acid in the sediments. A range of CSIRO and other reports showed that this affected 720 ha of the 940ha site. Between 1976 and 2004, it was estimated that at least 72,000 tonnes of sulfuric acid was released from the site, as well as soluble aluminium, iron, heavy metals and arsenic. Water bodies on site were routinely found to have a pH of 3.5 or lower. Aluminium levels were of particular concern, exceeding ANZECC guideline levels by as much as 6,000 times.

The discharge of acid and heavy metals led to death and dieback of vegetation (Figs 2 and 3) and had severe implications for aquatic life. These impacts were of particular concern due to the proximity of the site to the Great Barrier Reef Marine Park, with substantial evidence that acid sulfate soil runoff was discharging into reef receiving waters.

Figure 2a: Aerial view of Firewood Creek area from the 1980s showing extensive grasslands and Melaleuca leucadendra woodlands to the left of the bund wall roadway

Figure 2a: Aerial view of Firewood Creek area from the 1980s showing extensive grasslands and Melaleuca leucadendra woodlands to the left of the bund wall roadway.

Figure 2b: Aerial view of Firewood Creek area in 2013 with extensive flooded areas, Melaleuca woodland die-back and mangrove development.

Figure 2b: Aerial view of Firewood Creek area in 2013 with extensive flooded areas, Melaleuca woodland die-back and mangrove development.

Fig 3. Iron accumulation in oxidised sediments at the East Trinity site.

Fig 3. Iron accumulation in oxidised sediments at the East Trinity site.

Remediation, rehabilitation and restoration phase. The land was purchased by the QLD government in the year 2000, with the ‘Acid Sulfate Soil Remediation Action Plan’ commencing shortly thereafter. This involved a range of engineering solutions to achieved the desired hydrology and apply the lime-assisted tidal exchange remediation strategy, at first on a trial basis. Positive results during the trial period led to the long-term adoption of lime assisted tidal exchange (LATE) at East Trinity.

The LATE remediation strategy. Management strategies for acid sulfate soils are based on the principles of dilution, containment or neutralisation, with each bringing different benefits and challenges. Containment can lead to substantial acid build up and inhibit the movement of aquatic life, whilst the addition of agricultural lime can be costly. The LATE strategy (Fig. 4) was designed to support natural processes by reintroducing tidal flows, encouraging natural systems to restore the wetlands, hence greatly reducing the costs of lime and infrastructure, as well as hands-on management requirements. Flooding the soil stimulated reducing geochemical conditions whilst diluting the acidity. The bicarbonate in seawater provided a large source of alkalinity, whilst the organic matter present provided energy for microbial reactions to take place in the soil, thereby stimulating the in-situ production of alkalinity. Agricultural lime was added to the incoming tide to support the process, and also added to the out-going exit waters to prevent acid-flush into estuarine waters.

Fig 4. The image above shows some of the key parameters improved by the LATE bioremediation strategy.

Fig 4. The image above shows some of the key parameters improved by the LATE bioremediation strategy.

Results of the remediation project. The East Trinity site now has sediments at a spectrum of stages of remediation, with large areas fully remediated. Tidal inundation has ultimately led to a binding-up of heavy metals in the sediments and the neutralisation of acidity to a pH of 6.5, a typical pH for a subtropical estuarine environment. Following six years of gradually increasing tidal inundation, it was found that in-situ microbial and tidal exchange processes accounted for 99% of the change, whilst the addition of agricultural lime contributed less than 1%.

This greatly reduced the release of heavy metals to the estuarine environment and allowed for the re-establishment of mangrove and intertidal ecosystems (Fig. 2b).

Vegetation. Some ecological communities associated with the incursion of seawater and expansion of the tidal zones within the site have reduced while others have expanded. Mangrove communities have expanded and Acrostichum aureum (mangrove fern) fernlands have particularly increased, although some previous fernland transitioned to mangrove. Pasture areas have been largely replaced by Paperbark (Melaleuca leucadendra) shrublands and low woodlands and by the native grass Phragmites (Phragmites karka). The dieback of open forests of Paperbark impacted by the tidal areas continues, with some stands that were healthy in 2008 now in decline. Decline of low Clerodendrum inerme closed vinelands also continues in proximity to the tidal zone, though in other areas this community appears to be recovering.

Birds. A total of 136 species of birds have been observed at East Trinity since the rehabilitation began. Reports suggest that the expansion of mangrove and other higher elevation wetlands associated with the rehabilitation are likely to have benefited a number of bird species, including some internationally important shorebird species listed in agreements with China (CAMBA), Japan (JAMBA) and the Republic of Korea (ROKAMBA). Recently a new wader roosting site has emerged in mangroves on the northern boundary of the East Trinity area and it seems this may be significant in the regional context.

Future directions. The remediation of the East Trinity site has led to the area now having sufficiently high ecological function to be transferred back to Indigneous ownership and management.

The LATE remediation strategy’s regular tidal inundation will remain in place to ensure the acid sulfate soils remain protected from further oxidation; and monitoring and further research will continue into geochemical pathways to avoid degradation re-occurring.

Acknowledgements. The remediation of the East Trinity site and subsequent research has occurred due to the long-term efforts and collaborations between the Queensland Department of Science, Information Technology and Innovation (DSITI), CSIRO, the CRC for Contamination Assessment and Remediation of the Environment (CRC CARE) and Southern Cross University. Figures and data cited in this summary are derived from reports from these organisations available on request.

Contact. Prof Richard Bush, University of Newcastle (University Drive, Callaghan NSW 2308, Australia Tel: +61 (0)2 49215000; Email: .  Hanabeth Luke is an Associate Lecturer, Southern Cross University (Lismore, NSW 2480, Australia. Tel: +61 (0) 430092071; Email:

Stewartdale Nature Refuge koala habitat restoration in South Ripley, south east Queensland

Key Words: reconstruction, assisted regeneration, planning, koalas, conservation

Introduction: The Stewartdale Nature Refuge is located in South Ripley, south east Queensland on private land owned by the Sporting Shooters Association of Australia (SSAA). The 969 ha block contains live shooting ranges, large open areas dominated by pasture grasses, a substantial lagoon frequented by many bird species and extensive natural areas. The area being restored is 211 ha of dry sclerophyll vegetation, containing a number of Regional Ecosystems (REs) being restored through large scale planting (reconstruction) and assisted regeneration approaches. Its conservation value is heightened by the fact that it connects to the Karawatha Flinders Corridor, the largest remaining stretch of open eucalypt forest in south-east Queensland.

Condition ranges from large degraded areas (i.e. pasture) to native vegetation that contains both regrowth and remnant dry sclerophyll. All areas were impacted by varying levels of weed infestation due to previous clearing and ongoing disturbance from cattle grazing. Natural disturbances such as regular fire and periodic floods have also contributed to disturbance at the site. More than 30 weed species impact the project area at varying levels and the species and impacts vary with the condition of the land. Open areas were dominated by pasture grass such as Setaria (Setaria sphacelata) and Rhodes grass (Chloris gayana) in addition to fast growing annuals, although infestations of Leucaena (Leucaena leucocephala), Prickly Pear (Opuntia stricta) and large clumping Bamboo (Bambusa sp.) also required significant control efforts. In more forested areas (and underneath isolated remnant trees) weed species included Lantana (Lantana camara), Creeping Lantana (Lantana montevidensis), Corky Passionfruit (Passiflora suberosa), Easter Cassia (Senna pendula var. glabrata), Siratro (Macroptilium atropurpureum) and exotic grasses, annuals and groundcovers.

The aim of the project is to restore, native plant communities present within the Stewartdale project site to support local koala populations. Our goals are to:

  • Repair native vegetation including the structure, integrity and diversity to support koala populations
  • Strengthen the resilience and regenerative capacity of native vegetation
  • Restore and expand native regrowth vegetation by controlling weeds
  • Maintain the project site so weeds do not negatively impact the development and recovery of native vegetation
  • Protect drainage lines, gullies and slopes from erosion
  • Protect and enhance the water quality of Bundamba Lagoon
  • Construct fauna friendly fencing across the site with the aim of protecting planted trees from herbivory
  • Reduce the risk of fire moving through the site and impacting restoration works by conducting strategic slashing activities to reduce fuel loads.

Planning. A restoration plan was developed after detailed site assessments and negotiations with the landholder, land manager and state government were finalised integrating Nature Refuge conditions and current land use and future management requirements. The site was divided into zones and sub-zones to assist directing works including applying a range of restoration approaches – i.e. assisted regeneration and reconstruction (‘revegetation’) and several planting models and species mosaics to different parts of the site. Detailed maps were produced for each zone and included information such as the location of all tracks, fences, assisted regeneration zones, wildlife corridors, planting areas according to each RE and numbers of species and plants to be installed per zone. The plan also included detailed information on restoration approaches; weed control at all stages of the project; seed collection and propagation; site preparation including the specifications and location of all fencing, tracks, rip lines and areas of concern (i.e. identified hazards across the site); how to carry out all works in each zone; site maintenance requirements for 5-7 years; and monitoring requirements.

PP2b after site preparation.JPG

Fig 2. Preparation for planting  at Stewartdale Nature Refuge.

PP2b after planting Mar 2016

Fig 2. After planting to support local Koala population, Mar 2016.

Works to date. Site preparation commenced with the collection of seed from on and around the wider property and surrounds ensuring that all species to be planted were collected from a minimum of 10 widely spaced parent trees. Primary weed control started with the control of weeds in the 65 ha of assisted regeneration zones and the control of other woody weeds across reconstruction areas in preparation for slashing and other activities. More than 18 km of fauna friendly fencing (i.e. no barbed wire) was installed to protect planted stock from browsing by large herds of macropods and cows. Two large corridors were retained for fauna to reach Bundamba lagoon from different parts of the regional corridor as it is an important resource for many local and migratory fauna. Slashing across open areas was commenced and followed by the installation of rip lines to alleviate soil compaction and assist efficient planting activities. Weeds and pasture grasses were then sprayed out along all rip lines. 114 000 koala food and shelter trees were planted according to the RE for each section and according to the local conditions (i.e. whether it was low lying, on a ridge or near infrastructure). Some additional frost resistant and local Acacia species were also added to particularly frost prone areas to assist the development of a canopy and the protection of developing vegetation.

The 114 000 tubestock were installed over a 7 week period with the last stems being planted in April 2015. All trees were fertilised and watered at the time of planting and where possible, slashed grass spread across the rip lines to assist retaining moisture and slowing weed regrowth. (Follow-up watering was applied to all planted stock between September and October 2015) Nearly 2000 (1 m high) tree mesh guards were installed to protect planted stock in fauna corridors.

Series shot 1.1

Careful spot spraying to reduce weed while protecting natives

Series Shot 1.2

Growth of saplings is improved without competition.

Results to date. As of March 2016, weeds have been significantly reduced across the 65 ha of assisted regeneration areas. Unfortunately a wildfire fire went through approx. a third of the project area after primary and follow up weed control works had been completed. Fortunately the event was prior to planting though the fire did reduce the number of trees regenerating in assisted regeneration patches as many were too young to withstand the fire. New germinations are however occurring and the level of native grasses, groundcovers and other native species have increased due to ongoing weed control efforts.

Despite heavy frosts in winter 2015, a flood event in May 2015 (150 mm of rain fell in 1.5 hours) and now an extended dry period, the planting is developing well with the average height of trees at over a metre tall and mortality under 5%. Weed control is continuing across the project site with efforts currently concentrating on the control of many annual weeds such as Cobbler’s Peg (Bidens pilosa), Balloon Cotton (Gomphocarpus physocarpus) and Stinking Roger (Tagetes minuta) and many exotic grasses such as Setaria (Setaria sphacelata) and Rhodes grass (Chloris gayana) to reduce competition to planted stock. Assisted regeneration areas are being joined up to planting zones wherever possible to further assist the development of the site.

It should also be noted that Birds Australia have recorded 69 bird species on site.

Ongoing works: Regular maintenance continues on the site with the control of weeds particularly along rip lines where weed germination and growth is rapid. Slashing is also regularly done between the rip lines and along tracks and fence lines to assist access around the site and the management of fuel loads and therefore wildfire across the site. It is expected that the time it takes to complete each maintenance rotation will begin to reduce as plants become more established and start to develop a canopy.

Weed control will also continue in all assisted regeneration zones and is also expected to reduce with the development of native vegetation structure and diversity together with the reduction of the weed seed bank. Ongoing slashing, fence maintenance and monitoring will continue for another 3-5 years though the exact time period will be determined by the State government.

Monitoring including soil moisture readings, transects to assist determining survival rates across the site and photographic monitoring is regular and further supports 6 monthly reporting requirements.

Stakeholders and funding bodies: Department of Environment, Heritage and Protection, Queensland State Government; Sporting Shooters Association of Australia (SSAA). Photos: Ecosure.

Contact Information: Jen Ford (Principal Restoration Ecologist, Ecosure TEl: +61 (0)7  3606 1038.


Restoration at Numinbah Conservation Area, City of the Gold Coast, Queensland

Key Words: assisted regeneration, restoration planning, conservation

Introduction: Numinbah Conservation Area, located in the hinterland of the Gold Coast in south-east Queensland, is one of many natural areas managed by City of Gold Coast’s Natural Areas Management Unit (NAMU). The 598 ha property contains 12 Regional Ecosystems (REs) ranging from sub-tropical and dry rainforest to dry and wet sclerophyll types; and include riparian zones, steep areas, gullies and rocky outcrops. Its conservation value is heightened by the fact that it connects to other reserves including the World Heritage areas of Springbrook.

Condition ranges from large degraded areas (i.e. pasture) to native vegetation that contains both regrowth and remnant areas. All areas were impacted by weeds due to previous disturbance from logging and subsequent cattle grazing. More than 35 weed species impact the site at varying levels with the most notable species across the site being Lantana (Lantana camara). Edges are impacted by exotic vines such as Glycine (Neonotonia wightii), the understorey by many herbaceous weeds such as Mistflower (Ageratina riparia) and rainforest zones by persistent weeds such as Coral Berry (Rivina humilis) and Passion Vines (Passiflora spp.) to name a few. Approximately 60 hectares of open area are dominated by pasture grasses and other weeds.

The aim of the project is to restore, to the extent possible, the structure, function, dynamics and integrity of the pre-existing vegetation and the sustaining habitat that is provided. Our goals are to:

  • Improve the health of vegetation and habitat types across the site
  • Improve connectivity for flora and fauna
  • Reduce fuel levels in fire prone ecosystems and the risk of hot fires sweeping through the site and wider landscape
  • Increase the resilience of the site
  • Improve water quality
  • Increase the health, populations and distribution of threatened species – flora and fauna
  • Reduce the need for weed control maintenance over time i.e. to a level of minimal maintenance
  • Provide nature based recreational opportunities and environmental education along this section of the Gold Coast Hinterland Great Walk

Planning. An ecological restoration plan was developed after detailed site assessments and the site was divided into precincts, zones and sub-zones to assist directing works. Information in the plan included species lists, weed control information, maps and detail on how to restore each area and progressively link zones. A detailed fire management plan was also developed for the site that took into account wildfire mitigation, restoration zones, the location of threatened species, site objectives, REs including their recommended fire regimes, and the capacity of areas to regenerate.

Works to date. Works over the last 9 years have covered more than 190 ha. The main approach to restoration has been via assisted regeneration consisting mainly of large scale weed control and the fencing of areas to reduce the impact of cattle. Further works have involved planting a section of creek to assist stability and connectivity across a section of the site; and the propagation and translocation of four threatened flora species (details not disclosed for security reasons).

Where low intensity fuel reduction burns were conducted in dry sclerophyll vegetation, timely follow up weed control was applied to ensure re-shooting Lantana, Molasses Grass (Melinis minutiflora) and other weeds did not fill gaps and to support the colonisation and growth of native vegetation. In remnant and regrowth vegetation, systematic weed control using a range of techniques has been applied. E.g. large areas of Lantana were controlled using three techniques: cut, scrape and paint where it was in close proximity to native plants; over-spraying after isolating infestations; and, spot-spraying when it germinated or was re-shooting. Weed species were continually suppressed to ensure native species germinated and grew to a point where most gaps have been filled with native vegetation. As each area developed and maintenance reduced, efforts were put into continually expanding the work fronts.

A propagation and translocation project was also implemented in partnership with Seqwater. More than 1150 individuals (four species) have been propagated, planted into their particular niche and have been monitored and reported on annually. This will continue until all species are considered to be self-sustaining i.e. flowering, fruiting and reproducing.



(c) NCA8n_20090716




Figure 1, (a-f) represents an annual sequence of recovery after control of Lantana and subsequent weed at one photopoint from 2008 to 2011, with the last photo taken in 2015. The results reflect accurate and timely weed control to support the recovery of native vegetation. (Photos: City of Gold Coast)

Results to date. As of July 2015, weeds have been significantly reduced across the 190 ha treated area to a point where maintenance is being applied, with some areas requiring little to no maintenance. In a number of areas this reduction of weed has also significantly reduced fuel levels.

Increased abundance and diversity of native vegetation has occurred across a range of ecosystem and habitat types within the reserve. Open areas once dominated by dense Lantana have taken approx. 3 years to naturally regenerate with a range of pioneer, early secondary and later stage rainforest species (Figs 1-3). Many of those areas now include continuing recovery of later stage species and contain a large diversity of seedlings, groundcovers and ferns. More diverse communities have recovered with a large range of species (depending on the ecosystem / ecotone) and support a diversity of fauna species. Works in four of the larger precincts have now joined up and weed control works are continuing to expand all regenerating areas.

More than 7000 plants installed along the open riparian stretch are establishing with native species regenerating amongst the planting. After approx. 7 years the average height of the planted canopy is approx. 5-7m tall.

Ongoing works: All current work zones are being continuously extended ensuring progress made is maintained. The open area (e.g. paddock) is being reduced over time as vegetation is encouraged to expand (i.e. by continuing to control weeds to past the drip lines of all native vegetation). Fences that currently contain cattle (i.e. to assist managing open areas for access, fire management and to ensure funds are spent in more resilient areas) are being moved to continue to reduce the size of highly degraded areas. Fire management, large scale weed control and the monitoring and evaluation of threatened species, together with fauna surveys, is continuing.

Stakeholders and funding bodies: Natural Areas Management Unit (NAMU), City of Gold Coast and Seqwater. Contact Information Paul Cockbain, Team Leader Restorations +61 7 5581 1510


Donaghy’s Corridor – Restoring tropical forest connectivity

Key words: tropical forest restoration, habitat connectivity, small mammal recolonisation, ecological processes, community partnerships.

Introduction. Closed forest species are considered especially susceptible to the effects of forest fragmentation and habitat isolation. The Wet Tropics of north Queensland contains many forest fragments between 1ha and 500ha, mostly surrounded by dairy and beef pastures, and crops such as maize, sugar cane and bananas. Larger blocks are often internally fragmented by roads and powerlines. The Lake Barrine section of Crater Lakes National Park is a 498ha fragment that is 1.2km distant from the 80,000ha Wooroonooran N.P, and ecologically isolated since the 1940s with detectable effects on genetic diversity of rainforest mammals.

In 1995 the Qld Parks and Wildlife Service, along with landholders and the local ecological restoration group TREAT Inc., began riparian forest restoration along Toohey Creek to re-connect the Barrine fragment to Wooroonooran and to document colonisation by small mammals and native plants typically associated with rain forest environments (Fig 1).


Fig 1. Donahy’s Corridor, Atherton Tablelands, linking Crater Lakes NP and Wooroonooran NP, Qld (Photo TREAT).

Connectivity Works. Prior to works commencement, small mammal communities (e.g. Rattus spp. and Melomys spp.) along and adjacent to Toohey Creek were sampled, along with a full vegetation survey, to determine base-line community composition and structure. Permanent stock exclusion fencing was erected and off-stream stock watering points established.

A 100m wide corridor of vegetation was established over a four year period using local provenances of 104 native species comprising around 25% pioneer species, 10% Ficus spp., and the remainder from selected primary and secondary species. In total, 20,000 trees, shrubs and vines were planted along the creek, and a three-row shelterbelt was planted adjacent to the corridor to reduce edge effects. Species were selected on a trait basis, including suitability as food plants for targeted local fauna e.g. Cassowary (Casuarius casuarius johnsonii).

Ecological furniture (e.g., rocks, logs) was placed prior to planting. On completion, the 16ha Donaghy’s Corridor Nature Refuge was declared over the area, recognising the Donaghy family’s significant land donation and the corridor’s protection by legislation. A three year monitoring program, conducted quarterly, commenced on completion of planting.


Fig. 2. Developing rainforest in Donahys Corridor (Photo Campbell Clarke)

Monitoring. Flora monitoring was conducted along transects bisecting the four annual plantings (1995/96/97/98), and small mammal colonisation in 11, 20m x 20m plots located in the plantings, adjacent open paddocks, and in forests at either end. Small mammal sampling included mark-recapture and DNA studies, to determine colonisation and movement patterns and genetic effects.

Results. Three years after establishment, over 4000 native plants were recorded – representing 119 species from 48 families. This included 35 species naturally dispersed from the adjacent forest (Figs 2 and 3). Small mammal sampling showed 16 long-distance movements by Rattus species and the appearance of an FI hybrid Bush Rat (Rattus fuscipes) in the central section of the corridor in the third year of the study. The rainforest rodent Fawn-footed Melomys (Melomys cervinipes) had established territories in the second year of the study. A study of wood-boring beetles (Coleoptera)in ecological furniture showed 18 morpho-species in a three year period. Many other orders/families were also recorded.

Water quality in Toohey Creek was not studied but has continued to increase since the replacement exotic grasses with woody vegetation, and the exclusion of cattle from accessing the stream. There is increased shade available for stock and less pressure on the limited number of existing paddock shade trees.


 Fig. 3. Indicators of rainforest structure (species and layering) and functions (habitat providion, nutrient cycling, recruitment) are now highly evident. (Photo Campbell Clarke).

What we learned.

  • Plant colonisation was rapid, dominated by fleshy-fruited species (10-30mm diameter), of which a proportion are long-lived climax species
  • Plant colonisation was initially highest in the interior, close to the creek margin, but has become more even over time
  • Vegetation structural complexity and life form diversity have continued to increase since establishment
  • Small mammal communities changed in response to habitat structure, grassland species dominate until weeds are shaded out when they are replaced by closed forest species
  • Many long distance mammal movements occurred that were only detected by genetic analysis
  • Monitoring showed small mammals used the new habitat to traverse from end to end until resources were worth defending: at that time long distance movements declined and re-capture of residents increased
  • Partnerships between government, research bodies, community groups, and landholders are essential if practical solutions to fragmentation are to be developed and applied

Acknowledgements: Trees for the Evelyn and Atherton Tableland acknowledges and appreciates the support of all the volunteers involved in this project, staff from the Qld Parks and Wildlife Service-Restoration Services, , James Cook University, University of Qld, Griffith University and UCLA Berkely. In particular we would like to acknowledge the Donaghy family.

Contact: TREAT Inc. PO Box 1119, Atherton. 4883 QLD Australia.


Global Restoration Network Top 25 report:

Watch the video on RegenTV – presented by Nigel Tucker









Thiaki biodiversity-ecosystem functioning and restoration experiment


Fig 1. Research students measuring planted Queensland Maples for modelling studies

Noel Preece

Key words rainforest reforestation, carbon sequestration, cost-effectiveness, old fields, weeds

Introduction. Restoring agricultural landscapes to forest is time-consuming, expensive and often hit-and-miss. Trees take years to show survival and growth rates and effects of planting methods and maintenance. World-wide, there are few large-scale reforestation experiments designed to test the effectiveness of and functional responses to reforestation, especially in the tropical regions for biodiversity and carbon benefits.

In the wet tropics of Australia, far north Queensland, the Thiaki Restoration Research project was established to examine aspects of reforestation (Figs 1-3). The reference model for the project is ‘Simple to complex notophyll vine forest of cloudy wet highlands on basalt, Regional Ecosystem 7.8.4’. Three fully-replicated experiments were established in 2010, 2011 and 2013 to examine different approaches to reforestation. The experimental plots are all replicated, with control plots, to examine different aspects of reforestation. Plot size varies from 25 m square up to 50 m square, and we now manage 90 experimental plots over more than 30 hectares of planted land.

Experimental design. The first experiment is examining the effect of different planting methods; the second is researching three combinations of native rainforest species and two treatments (high and low planting densities); and the third is examining the effects of two different herbicide treatments (blanket spraying and strip spraying). One of the major emphases of the experiments is to analyse planting practices for their cost-effectiveness for the carbon sequestration industry. Reducing establishment and maintenance costs for carbon sink forests is essential, as published and anecdotal costs of establishing forests in the region and elsewhere has been so high as to make the carbon economy unreachable for environmental planting practitioners to ‘make a buck’ from carbon farming. We will publish these findings in the near future, as most of the plantings have reached an (almost) self-maintaining height and size.

Current work, which will be published from the experiments, includes:

  • examination of field-based measurements compared with national modelling tools;
  • effects of herbicide spraying and grass suppression practices; rates and patterns of natural recruitment;
  • functional responses of trees to soil nutrients and characteristics (such as compaction, moisture and organic content); functional responses of dung beetles and mammals to restoration;
  • responses of ants to restoration and remnant patches and proximity to remnant forests; and
  • the functioning of barriers to recruitment by rainforest fauna.

Weeds also present a significant research component, and examination of the effects and faculty of weeds to restoration is being conducted. We are also examining the effects of different planters on survival rates, which is of vital interest to restorationists.


Fig. 2. Sampling soils and roots to study functional responses of tree families.

Results to date. The experiments have resulted in important findings which affect reforestation success, and publications which have contributed some of the first replicated experimental results on: planting methods; allometrics for young trees; functional responses of several taxa to restoration; young tree root:shoot ratios; improved wood density data on young trees; and cost-effectiveness of planting methods. Some of the related research has contributed to better Australian models of carbon sequestration in the tropics.

Lessons learned and future directions. Top priority lessons include the preparation and planting stage, as all else follows and mistakes made at this point ramify later. Vital considerations are: site preparation, especially early weed control; selecting species which will survive the harsh exposed conditions; nurturing and sun-hardening seedlings; ensuring that the soil is very wet and that seedlings are soaked immediately before planting; and, ensuring that planters plant in ways that don’t damage the seedlings.

Collaborators. Charles Darwin, James Cook, Adelaide, Lancaster (UK), and Queensland Universities. Funding: Australian Research Council Linkage project LP0989161, Biome5 Pty Ltd, Terrain NRM, Greening Australia, Stanwell Corporation, Biodiversity Fund.

Contact. Dr Noel Preece, Director, Biome5 Pty Ltd, PO Box 1200, Atherton Qld 4883, +61407996953; email: Website

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Conserving and restoring biodiversity of the Great Barrier Reef through the Representative Areas Program (RAP)

Key words: Coral reef, no take zones,

The Great Barrier Reef is the world’s largest coral reef ecosystem (344,400 square km) and a World Heritage Area on the north-east coast of Australia. It contains a high diversity of endemic plants, animals and habitats. It is a multiple-use area with different zones in which a wide range of activities and uses are allowed, including tourism, fishing, recreation, traditional use, research, defence, shipping and ports. Components of the ecosystem have been progressively showing symptoms of decline.


Coral Trout is one of more than 1625 fish found on the Great Barrier Reef

Existing ecosystems. Coral reefs are like the building blocks of the Great Barrier Reef, and comprise about seven per cent of the ecosystem. The balance is an extraordinary variety of other marine habitats and communities ranging from shallow inshore areas to deep oceanic areas over 250 kilometres offshore and deeper than 1000 metres, along with their associated ecological processes. The abundant biodiversity in the Great Barrier Reef includes:

  • Some 3000 coral reefs built from more than 400 species of hard coral
  • Over one-third of all the world’s soft coral and sea pen species (150 species)
  • Six of the world’s seven species of marine turtle
  • The largest aggregation of nesting green turtles in the world
  • A globally significant population of dugongs
  • An estimated 35,000 square kilometres of seagrass meadows
  • A breeding area for humpback whales and other whale species
  • More than 130 species of sharks and rays
  • More than 2500 species of sponges
  • 3000 species of molluscs
  • 630 species of echinoderms
  • More than 1625 species of fish
  • Spectacular seascapes and landscapes such as Hinchinbrook Island and the Whitsundays
  • 215 species of bird
Crown-of-thorns single injection (C) GBRMPA cropped

Diver injecting Crown of Thorns Starfish

Impacts on the ecosystem. The main threats to the Great Barrier Reef ecosystem are:

  • Climate change leading to ocean acidification, sea temperature rise and sea level rise
  • Catchment run-off of nutrients, pesticides and excessive sediments
  • Coastal development and associated activities such as clearing or modifying wetlands, mangroves and other coastal habitats
  • Overfishing of some predators, incidental catch of species of conservation concern, effects on other discarded species, fishing of unprotected spawning aggregations, and illegal fishing.
4. GBRMPA staff - public consultation(2)

GBRMPA staff meeting to plan and discuss Representative Areas Program (RAP) at Townsville offices

Restoration goals and planning. A primary aim of the Great Barrier Reef Marine Park Authority (GBRMPA) is to increase biodiversity protection, with the added intent of enabling the recovery of areas where impacts had occurred. A strong foundation for this has been achieved through the Representative Areas Program, by developing a representative and comprehensive network of highly protected no-take areas, ensuring they included representative examples of all different habitat types.

The rezoning also provided an opportunity to revise all the zone types to more effectively protect the range of biodiversity.

A further aim was to maximise the benefits and minimise the negative impacts of rezoning on the existing Marine Park users.

These aims were achieved through a comprehensive program of scientific input, community involvement and innovation.

More information on the extensive consultation process is available at

6. green and yellow zone examples

An example of Green Zones (marine national park) and Yellow Zones  (conservation park)

Monitoring. An independent scientific steering committee with expertise in Great Barrier Reef ecosystems and biophysical processes was convened to define operational principles to guide the development of a comprehensive, adequate and representative network of no-take areas in the Marine Park (Fernandes et al 2005). Science (both biophysical and social science) provided the best available information as a fundamental underpinning for the Representatives Areas Program.

There are currently over 90 monitoring programs operating in the Great Barrier Reef World Heritage Area and adjacent catchment. These programs have largely been designed to address and report on specific issues, location or management.

Reef management. GBRMPA’s 25-year management plan outlines a mix of on-ground work, policies, strategies and engagement. The actions include:

  • increasing compliance focus to ensure zoning rules are followed
  • controlling Crown-of-thorns Starfish (Acanthaster planci) outbreaks
  • ensuring cumulative impacts are considered when assessing development proposals
  • setting clear targets for action and measuring our success
  • monitoring the health of the ecosystem on a Reef-wide scale
  • implementing a Reef Recovery program to restore sites of high environmental value in regional areas — regional action recognises the variability of the Reef over such a large area and the variability of the issues and interests of communities and industries in each area.

Benefits of zoning to date. The benefits reef ecosystem health are already occurring including:

  • More and bigger fish: Larger fish are important to population recovery as they contribute more larvae than smaller fish. James Cook University research shows the network of no-take marine reserves benefits species of coral reef fish targeted by fishers (especially Coral Trout), with not only more fish, but bigger fish in reserves — some zones have around twice as much fish biomass compared to zones open to fishing.
  • Improved fish recruitment: Research in the Keppel Islands suggests increased reproduction by the more abundant, bigger fish in reserves. This not only benefits populations within those reserves, it also produces a ‘spill over’ when larvae are carried by currents to other reefs, including areas open to fishing.
  • Improved resilience: The spillover effects also mean the connectivity between reserve reefs is intact. Spatial analysis shows most reserve reefs are within the dispersal range of other reserve reefs, so they are able to function as a network.
  • Sharks, dugongs and turtles: These species are harder to protect because they are slow growing and slow breeding. They are also highly mobile, moving in and out of protected zones. Despite this, available evidence shows zoning is benefiting these species.
  • Reduced crown-of-thorns starfish outbreaks: Outbreaks of crown-of-thorns starfish appear to be less frequent on reserve reefs than fished reefs. This is particularly important as Crown-of-thorns Starfish have been the greatest cause of coral mortality on the Reef in recent decades.
  • Zoning benefits for seabed habitats: Zoning has improved protection of seabed habitats, with at least 20 per cent of all non-reefal habitat types protected from trawling.

How the project has influenced other projects. In November 2004, the Queensland Government mirrored the new zoning in most of the adjoining waters under its control. As a result, there is complementary zoning in the Queensland and Australian Government managed waters within the Great Barrier Reef World Heritage Area.

The approach taken in the Representative Area Program is recognised as one of the most comprehensive and innovative global advances in the systematic protection and recovery of marine biodiversity and marine conservation in recent decades and has gained widespread national international, and local acknowledgement of the process and outcome as best practice, influencing many other marine conservation efforts.

Stakeholders. As a statutory authority within the Australian Government, the Great Barrier Reef Marine Park Authority is responsible for managing the Marine Park. However, as a World Heritage Area, management of the ecosystem is complex jurisdictionally.

Both the Australian and Queensland governments are involved in managing the waters and islands within the outer boundaries through a range of agencies. GBRMPA works collaboratively with the Queensland Parks and Wildlife Service through the joint Field Management Program to undertake day-to-day management of the Great Barrier Reef, including its 1050 islands, many of which are national parks. The program’s activities include surveying reefs and islands, dealing with environmental risks such as ghost nets and invasive pests, responding to incidents, maintaining visitor facilities, and upholding compliance with Marine Park legislation and the Zoning Plan.

A wide range of stakeholders have an interest in the Great Barrier Reef, including the community, Traditional Owners, a range of industries and government agencies, and researchers. The public, including the one million people who live in the adjacent catchment (around 20 per cent of Queensland’s population), benefit from economic activities. In recent years, the number of tourists carried by commercial operators to the Great Barrier Reef averaged around 1.6 to 2 million visitor days each year (GBRMPA data) with an estimate of an additional 4.9 million private visitors per annum.

Resourcing. The resourcing required for rezoning of the Great Barrier Reef over the five-year period of the RAP (1999–2003) was significant. It became a major activity for the agency for several years, requiring the re-allocation of resources particularly during the most intense periods of public participation. However, the costs of achieving greater protection for the Reef are readily justified when compared to the economic benefits that a healthy Great Barrier Reef generates every year (about AUD$5.6 billion per annum).

Further information:


All images courtesy Great Barrier Reef Marine Park Authority


Dewfish Demonstration Reach: Restoring native fish populations in the Condamine Catchment

Key words: native fish, riparian habitat, fish passage, aquatic habitat, Native Fish Strategy

The Dewfish Demonstration Reach is a 110 kilometre stretch of waterway in the Condamine catchment in southern Queensland consisting of sections of the Condamine River, Myall Creek and Oakey Creek near Dalby. The Reach was established in 2007 with the purpose of promoting the importance of a healthy river system for the native fish population and the greater river catchment and demonstrating how the restoration of riverine habitat and connectivity benefits native biodiversity and local communities. Landholders, community groups, local governments and residents have worked together to learn and apply new practices to improve and protect this part of the river system.

The purpose of the project is to demonstrate how the restoration of riverine habitat and connectivity benefits native biodiversity and promote the importance of a healthy river system for native fish and the greater river catchment. The goal is to restore native fish populations to 60% of pre-European settlement levels and improve aquatic health within the Reach.

Image 3 - Adding structural timber to Oakey Creek

Fig 1. Adding structural timber to Oakey Creek

Image 4 - Installing a fish hotel into Oakey Creek

Fig 2. Installing a fish hotel into Oakey Creek

Works undertaken. A range of activities to improve river health and native fish communities have been undertaken primarily at seven key intervention sites within the Dewfish Demonstration Reach. These include:

  • Re-introduction of large structural habitat at five sites, involving the installation of 168 habitat structures consisting of trees, fish hotels, breeding pipes and Lunkers (simulated undercut banks).
  • Improvement of fish passage (by more than 140 km) with the upgrade of the fishway on Loudoun Weir and the installation of two rock-ramp fishways on crossings in Oakey Creek.
  • Ongoing management of pest fish, involving carp angling competitions, carp specific traps, electrofishing and fyke nets.
  • Rehabilitation of the riparian vegetation over 77 km of the Reach using stock exclusion fencing, off-stream watering points, weed control and replanting of native vegetation. In Dalby, a 1 metre wide unmown buffer was established on the banks Myall Creek.

Twice-yearly monitoring using a MBARCI model (multiple-before-after-reference-control-intervention) was undertaken to detect the local and reach-wide impacts of the intervention activities. Surveys involved sampling of the fish assemblage at fixed sites and assessment of the instream and riparian habitat.

Image 5 - Wainui crossing before the fishway

Fig. 3 Wainui crossing before the fishway

Image 6 - Wainui crossing after installation of the rock-ramp fishway

Fig 4. Wainui crossing after the installation of the rock ramp fishway

Results. The surveys indicated many of the intervention activities had a positive impact. The fish assemblage and riparian habitat improved at all intervention sites in the Dewfish Demonstration Reach since rehabilitation activities commenced.

The fish assemblages at introduced habitat structures were very similar to those found on natural woody debris, suggesting the introduced habitat is functioning well as a surrogate.

There were significant increases in the abundance of larger fish species, including Golden Perch (Macquaria ambigua) (up to 5-fold), Murray Cod (Maccullochella peelii peelii) (from absent to captured every survey), Spangled Perch (Leiopotherapon unicolor) (up to 9-fold) and Bony Bream Nematolosa erebi (up to 11-fold) in intervention sites following re-snagging. Murray Cod and Golden Perch are now consistently being caught from introduced woody structures and local anglers are reporting that the fishing has improved greatly. Despite this increase there is still limited evidence of recruitment in the area. There have also been small increases in Eel-tailed Catfish (Tandanus tandanus) and Hyrtls Tandan (Neosilurus hyrtli) abundances and a limited amount of recruitment has been observed for these species.

The abundance of smaller native fish has improved significantly in response to the intervention activities undertaken, especially where bankside and instream vegetation was improved. In Oakey Creek Carp Gudgeon (Hypseleotris spp.) abundance increased 1200-fold, Murray-Darling Rainbowfish (Melanotaenia fluviatilis) increased 60-fold and the introduced species Mosquitofish (Gambusia holbrooki) increased 9-fold following intervention activities.

Establishment of a bankside unmown buffer on Myall Creek has enabled natural regeneration of vegetation and resulted in significant increases in aquatic vegetation and native trees. This has led to substantial increases in the smaller bodied native fish assemblage, including a 3-fold increase in Bony Bream, 237-fold increase in Carp Gudgeon, 60-fold increase in Murray-Darling Rainbowfish and a 35-fold in the introduced Mosquitofish.

The abundance of pest fish remains low, except for Mosquitofish which have increased in abundance with the improvements in the aquatic vegetation. There is little evidence of Carp recruitment (Cyprinus carpio), suggesting active management may continue to suppress the population and minimise this species impacts in the Reach.

Image 1 - Myall Creek prior to restoration

Fig 5.  Myall Creek prior to restoration

Image 2 - Myall Creek after restoration

Fig 6. Myall Creek after restoration

Lessons learned and future directions. Improvements of the waterway health and ecosystems can lead to positive responses from native fish populations.

  • Targeting rehabilitation activities to specific classes of fish has been very effective.
  • Introducing habitat structures has been effective for larger fish, and
  • Re-establishing healthy bankside and aquatic vegetation has been vital in boosting the abundance of juveniles and smaller species.

Improvements in the extent of aquatic vegetation have unfortunately also resulted in increased numbers of the introduced pest, Mosquitofish. However, the overall benefits to native fish far outweigh impacts from the increase in the Mosquitofish population.

Stakeholders and Funding bodies. A large number of stakeholders have been involved in this project. The project’s success is largely due to the high number of engaged, involved and committed stakeholders. Without this broad network, costs to individual organizations would be higher and strong community support less likely.

Major funding has been provided by the Murray Darling Basin Authority, Condamine Alliance, Queensland Department of Agriculture and Fisheries and Arrow Energy.


Contact. Dr Andrew Norris, Senior Fisheries Biologist, Queensland Department of Agriculture and Fisheries, Bribie Island Research Centre, PO Box 2066, Woorim, QLD 4507; Tel (+61) 7 3400 2019; and Email:


Finbox demonstration reach toolbox:

Native Fish Strategy – first 10 years.

Demonstration reaches – Looking back, moving forward

Monitoring in demonstration reaches


Managing fire for nature conservation in subtropical woodlands

Emma Burgess, Murray Haseler and Martine Maron

Introduction. A study investigating the response of bird assemblages to mosaic burning is being conducted on 60,000 hectares private nature reserve in the Brigalow Belt bioregion of Queensland (Fig 1). The Brigalow Belt has recently experienced high rates of native vegetation clearing, motivating Bush Heritage Australia (BHA) to purchase and protect the property in 2001. The subsequent removal of cattle and horses from Carnarvon Station Reserve has increased grass and herb biomass. The seasonal surge in productivity the property now experiences however, increases the potential for more intense, frequent and extensive fires in hot, dry conditions. The risk of such wildfires needs to be managed, and a common approach to such management is prescribed burning. But how to ensure nature conservation objectives are still met?

Fig 1. Locality map of Carnarvon Station Reserve

Fig 1. Locality map of Carnarvon Station Reserve

In fire ecology, there is a common assumption that if we introduce a range of burn conditions to produce a mosaic of patches with different fire histories (pyrodiversity) – then the resulting diversity in fire histories and the greater representation of successional stages of vegetation is expected to accommodate more species in a given area (Fig. 2). Reducing the spatial scale at which fire history turns over- the “breaking up” of country- is also known as the patch mosaic burning approach.

Fig 2. Diagram of mosaic burning approach

Fig 2. Diagram of mosaic burning approach

Whilst we assume that pyrodiversity will give us increased habitat diversity, and therefore greater animal diversity, there is uncertainty as to the scale (alpha, beta or gamma diversity) at which pyrodiversity might influence biodiversity (Fig. 3). Alpha diversity is the total number of different species within a site or habitat; beta diversity is the difference in species composition between sites or habitats; and gamma diversity is the number of different species across all sites or habitats in the area of interest. At what spatial scale do we see the benefit for birds of mosaic burning (Fig. 3)?

Fig 4. Fire-sensitive semi-evergreen vine-thicket extending into Mountain Coolibah (Eucalyptus orgadophila) woodland, Carnarvon Station Reserve

Fig 4. Fire-sensitive semi-evergreen vine-thicket extending into Mountain Coolibah (Eucalyptus orgadophila) woodland, Carnarvon Station Reserve

Methods: We examine the relative influence of the diversity of fire histories, spatial configuration of these fire histories, spatial extent of particular fire histories and other measures of environmental heterogeneity on:

  1. Aggregated measures of bird species richness at both the landscape- (100 ha) and local-scale (1 ha); and
  2. Response of different bird foraging guilds to mosaic burning, at both the landscape- and local-scale.

 So what did we find? The diversity of fire regimes in the 100-ha landscape did not correlate with average site (alpha) or landscape- (gamma) diversity of birds. Rather, the total area of longer-unburnt vegetation was important for increasing bird richness at the landscape-scale, and sites in longer-unburnt vegetation had more species.

Although areas burnt in prescribed burns supported lower bird diversity compared to long-unburnt areas, prescribed burns are still necessary to reduce the risk of extensive wildfire. Such burns should focus on breaking up areas of high fuel at the beginning of the dry season (Fig. 4). The extent of long-unburnt vegetation that can be maintained with careful fire management is yet to be determined, but its importance as bird habitat is clear.

Acknowledgements: This work could not have been completed without funding and logistical support provided by AndyInc Foundation, Bush Heritage Australia and UQRS. Thanks to Peta Mather and Donna Oliver who assisted with field work. This study was carried out with approval from the Animal Ethics Committee at the University of Queensland (approval no. SGPEM/325/11/UQ).

Fig 4. Fire-sensitive semi-evergreen vine-thicket extending into Mountain Coolibah (Eucalyptus orgadophila) woodland, Carnarvon Station Reserve

Fig 4. Fire-sensitive semi-evergreen vine-thicket extending into Mountain Coolibah (Eucalyptus orgadophila) woodland, Carnarvon Station Reserve

Contact: Dr Emma Burgess University of Queensland, Email:

[This project summary is a precis of a talk presented to the Nature Conservation Council of NSW’s 10th Biennial Bushfire Conference, ‘Fire and Restoration: Working with Fire for Healthy Lands’ 26-27 May 2015. For full paper see:

Assessing the effectiveness of Integrated Pest Management in Queensland

Key words: Integrated Pest Management, pest fish control, Native Fish Strategy

Threats and Impacts: Carp (Cyprinus carpio) are believed to impact on native fish communities by increasing turbidity, up-rooting delicate shallow-rooted vegetation, competing with native fishes and other aquatic fauna for food and space, and indirectly promoting the development of toxic algal blooms.

All of the currently available methods for Carp control have limitations. Integrated Pest Management (IPM) involves the application of a range of technologies applied simultaneously, and focussing on achieving broader objectives (e.g. improved habitat) rather than simply reducing pest numbers.

Broad aim and specific objectives: The objectives of this project were to apply a range of Carp control techniques, as an integrated package, to:

  • intensively reduce Carp at a particular location, and measure the response;
  • achieve a significant reduction in damage caused by Carp using existing techniques; and,
  • demonstrate to the community the commitment to on-ground control.

The study was conducted at four lagoon sites, two in the Condamine River catchment, and two in the Macintyre river catchment.

Methods: One lagoon in each catchment was selected as an experimental site for intensive carp removal, and the other was used as a reference site which received no carp treatment.

Each site was sampled on eight occasions for the following response variables: water quality (temperature, pH, conductivity, turbidity, dissolved oxygen, light penetration, available forms of nitrogen and phosphorus); phytoplankton biovolume and diversity; zooplankton biomass and diversity; benthic macroinvertebrate abundance and diversity; native fish abundance, biomass and diversity; carp abundance, biomass and size distribution; and abundance of piscivorous birds and turtles.

One sampling event was conducted before the carp reduction treatment and a further seven samples were performed after Carp reduction. Carp removal employed a variety of methods based on boat electrofishing, gill nets, fyke nets, angling, commercial-scale netting and traps, and screens to prevent re-entry of Carp.

Figure 1: electrofishing during carp removal at rainbow lagoon. (Photo courtesy Peter Gehrke)

Figure 1: electrofishing during carp removal at rainbow lagoon. (Photo courtesy Peter Gehrke)

Figure 2: Researcher Sarah St Pierre live picking macroinvertebrates (Photo courtesy of Nissa Murphy)

Figure 2: Researcher Sarah St Pierre live picking macroinvertebrates (Photo courtesy of Nissa Murphy)

Findings: In Rainbow Lagoon (one of the experimental sites), Carp removal achieved an estimated 51% reduction in abundance and 43% biomass reduction, compared with 41% abundance and 33% biomass reductions in Warra Lagoon (the other experimental site). Reduction of Carp biomass by approximately 30 kg per ha allowed a threefold increase of more than 90 kg per ha in native fish that are eaten by larger fish species and fish-eating birds.

The size and weight of Carp removed differed markedly between Warra Lagoon and Rainbow Lagoon. Rainbow Lagoon had large numbers of small Carp, while Warra Lagoon had relatively large numbers of big Carp, with relatively few small individuals. The differences in Carp populations between lagoons are likely to result in different ecosystem responses over time.

Boat electrofishing was the most effective method of Carp removal used; fyke nets were the second most effective method, while the number of Carp removed by angling was far lower than other methods.

A succession of ‘transient’ responses to Carp reduction was observed in treatment lagoons. Whilst the exact nature of succession differed between lagoons, the generalised pattern following Carp reduction was evidenced as (i) an increase in biomass of large zooplankton; (ii) an increase in abundance of benthic macroinvertebrates; and (iii) increased biomass of gudgeons (Hypseleotris spp.) and Bony Herring (Nematalosa erebi).

These results suggest that of the full set of potential ecosystem responses to Carp reduction, only a subset may be demonstrated in individual locations because of the influence of local drivers and constraints. Due to a range of factors, the environmental responses of several variables, including water quality, macrophytes, zooplankton and macroinvertebrates, could not be linked to Carp control.

Lessons learned and future directions:Modest reductions in Carp biomass can provide significant benefits for native fish and, if continued, may be expected to translate into longer-term increases in native fish populations.

  • Carp in turbid wetlands interact strongly with native fish through pelagic food web pathways involving zooplankton, as well as benthic macroinvertebrate pathways.
  • Carp reduction has the potential to contribute significantly to restoring populations of native fish by increasing food availability.
  • Environmental outcomes of Carp reduction include direct conservation benefits to native fish, potential increases in popular recreational species and improved aquatic ecosystem health.
  • Piscivorous fish (e.g. Murray cod, Maccullochella peelii) are likely to have increased prey availability as a result of Carp reduction.
  • Improving native fish populations in key wetlands by reducing Carp biomass may strengthen the value of permanent lagoons as drought refuges for native fish.

Stakeholders and Funding bodies: This project was funded through the Murray-Darling Basin Authority’s Native Fish Strategy.

Contact: Sarah St Pierre, SMEC. Tel: + 61 (07) 3029 6600.


From Rainforest to Oil Palms and back again: a Daintree Rainforest Rescue in far north Queensland

Robert Kooyman, Joe Reichl, Edie Beitzel, Grant Binns, Jennifer Croes, Erryn Stephens, and Madeleine Faught

The establishment of Oil Palm (Elaeis guineensis) plantations is responsible for massive rainforest clearing and destruction throughout the tropics of Southeast Asia and beyond, and has captured the attention of conservation organisations around the world. One such organisation is Rainforest Rescue (RR), a not for profit Australian based conservation NGO. Through local and international projects (including in the Daintree region of Australia and Sumatra in Indonesia) RR has undertaken conservation actions that include removal of Oil Palm plantations to re-establish rainforest close to National Park areas.

The rainforest of the Daintree region provides an active window into the evolution, biogeography, and ecology of the southern (Gondwanan) rainforests, and their interaction with Indo-Malesian floristic elements. It has many (ca. 120) federal- and state- listed Threatened, Vulnerable, Of Concern, and Rare plant and animal species and a range of rainforest types.

To achieve restoration of a small (27.6 ha) but important piece of the global distribution of lowland tropical rainforest, RR purchased Lot 46 Cape Tribulation Road in the Daintree area of far north Queensland, Australia in 2010 and, in 2012, secured funding to set the property on its long journey back to rainforest.

The property was partly cleared in the 1960s, first for cattle grazing and later for Oil Palm cultivation. It has a mix of cleared (ca. 11 ha) and early stage natural regeneration (ca. 10ha) areas, bounded on two sides by more intact and mature rainforest (ca. 7 ha). Soils are mostly free-draining sandy clay loams on flat terrain

The on-ground works.  The property was divided into five working Zones as part of the restoration planning process (Fig. 1). Because of a nearby large seed source forest a key objective of the project is to maximise and protect natural regeneration, as well as planting larger openings. Up to 30,000 trees representing 100 species are expected to be planted during the 2-year life of the project, with around 10 ha of natural regeneration interspersed.

Figure 1. Map showing property, work zones (ZONE 1-5), permanent photographic points (Photo point 1-9), location of planting trials (Zones 1 and 2), and primary weed control area (2013) in orange. (Courtesy Google Earth)

Figure 1. Map showing property, work zones (ZONE 1-5), permanent photographic points (Photo point 1-9), location of planting trials (Zones 1 and 2), and primary weed control area (2013) in orange. (Courtesy Google Earth)

Trial tree plantings were undertaken in early 2011 and 2012, and selective weed management (herbicide based grass and soft weed control) began at the same time to optimise natural regeneration prior to identifying and preparing suitable planting sites.

Plantings.  The planting trials were each one hectare in area and designed to test the efficacy of two different high diversity (60-90 species) planting designs. In Zone 1 tree spacing was 2.5m, and in Zone 2 the spacing was 1.5m. Seedlings for rainforest plantings were propagated and grown in the RR nursery in the Daintree lowlands. Seed collection was undertaken north of the Daintree River and included seed collected from the property. A low number of vines were included in the species mix for subsequent plantings.

A total of 90 species have been planted to date. The species mix included some early stage (pioneer type) tree species from genera such as Polyscias (Araliaceae), Alphitonia (Rhamnaceae), Macaranga (Euphorbiaceae) and Commersonia (Malvaceae); and tall fast growing species such as Elaeocarpus grandis (Elaeocarpaceae) and Aleurites moluccana (Euphorbiaceae). The remaining species represented mostly moderately fast growing species, and some slower growing mature phase rainforest species.

Weed control. Where possible, large Oil Palms were removed mechanically, but to protect existing rainforest regeneration many required stem injection with herbicide. Several methods are currently being trialled to determine the most time and cost effective approach to controlling this large and difficult weed.

Late in 2012 and early in 2013 extensive mechanical and chemical weed control was undertaken in Zones 3, 4 and 5 (Fig. 1). This included mechanical clearing of large areas dominated by Giant Bramble (Rubus alceifolius) and other weeds, and some mechanical removal of Oil Palm seedlings on the southern side of the creek that traverses the property (Zones 3 and 4). Follow up chemical control (systematic backpack spraying of glyphosate) was conducted immediately (as required) to complete the site preparation for planting. This was targeted at grasses, broad-leaf weeds, and regrowth of woody weeds.

Monitoring design. Monitoring plots (7 / 50 x 20m plots, each with 10 / 10 x 10m subplots) and permanent photographic points (12 in total, 7 in association with monitoring plots) were established in the five working Zones. Cover, number of species and density will be recorded in these plots at each stratum at 12 month intervals. One monitoring plot was established in each of Zones 1 and 2, three in Zone 3 (including directly adjacent to Zone 4), and two in Zone 5 (in the north of the property; yet to be measured). Zone 4 will be monitored visually and by photo point as it is mostly natural regeneration enhanced by weed control.

Preliminary Results. The first round of project monitoring (year 1 establishment) provided base-line information for future development of the plantings and natural regeneration through assessing canopy cover, leaf litter cover, and a range of other factors that will change over time (Table 1). Informal observations have shown that site dominance was achieved by the trees planted 12 and 18 months ago in Zones 1 and 2.  Substantial numbers of wildling seedlings (of up to 11 species in a plot; and 15 in total) were found in the sites monitored prior to more recent planting.

Mechanical weed control was reported to be extremely effective and the operator was able to minimise damage to existing regrowth of species such as Melicope elleryana (Rutaceae), Glochidion harveyanum var. harveyanum (Phyllanthaceae), Macaranga involucrata var. mallotoides (Euphorbiaceae), Polyscias australiana (Araliaceae), Rhodamnia sessiliflora (Myrtaceae), Alphitonia incana (Rhamnaceae) and Aidia racemosa (Rubiaceae). In combination with the early implementation of broad and targeted spraying this maximised the retention of substantial existing saplings and seedlings.

Project funding will cease in 2014, and control of all weeds and rainforest establishment is expected to be completed in 2015; with only minor weed control required thereafter once canopy cover is established. Monitoring will continue at 12 month intervals and inform future publications.

Acknowledgements: The project is dependent on the generous support of RR donors and the on-going efforts of RR staff in FNQld. Funding for the project was provided by a Federal Government Biodiversity Fund Grant.

Contact:  Robert Kooyman, National Herbarium of NSW, Royal Botanic Gardens and Domain Trust, Mrs Macquaries Road, Sydney 2000 Australia.   Email:;

Figure 2 Mechanical weed control in Zone 3 (January 2013) prior to planting. Note remaining natural regeneration.

Figure 2 Mechanical weed control in Zone 3 (January 2013) prior to planting. Note remaining natural regeneration.

Figure 3. Newly planted trees in Zone 3 (March 2013). Note surrounding natural regeneration.

Figure 3. Newly planted trees in Zone 3 (March 2013). Note surrounding natural regeneration.

Figure 4. Zone 2 planting trial established in late 2011 at 18 months. Tree spacing at 2 - 2.5m.

Figure 4. Zone 2 planting trial established in late 2011 at 18 months. Tree spacing at 2 – 2.5m.

Table 1.  Synthesis of baseline data for natural regeneration, and progress (including planting) up to February 2013 measured on (50 x 20m) permanent monitoring plots (PP), in Zones (1,2,3), by Themes (1 – planting; 2 – natural regeneration). PD – total planted diversity on plot; PS(n) – number of seedling planted on plot; WS – wildling seedlings (0.5-1m in height); WD – wildling diversity; Av. CC(%) – Average Canopy Cover (%); Av. L(%) – Average Litter Cover (%); Av. LBC(%) – Average Log-Branch Cover (%); Av. PCHt – Average planted canopy height (m); dbh – diameter at breast height (1.3m); NR – Number of stems, natural regeneration >1cm DBH; NR-div – Diversity of natural regeneration >1cm DBH; Age (mths) – Age of planting in months. Zone 4 (not shown) has permanent photo points and visual monitoring.

PP Zone Theme PD PS(n) WS WD Av.CC(%) Av.L(%) Av.LBC(%) Av. PCHt NR NR-div Age(m)



1, 2








0.6 – 1






1, 2














1, 2








































Appendix 1 List of main weed species located and treated on the property.

Common Name Species Family Life Form
Sanchezia Sanchezia parvibracteata Acanthaceae herb
Brillantaisia Brillantaisia lamium Acanthaceae herb
Goosefoot Syngonium podophyllum Araceae vine
Toothed Philodendron Philodendron lacerum Araceae climber
Oil Palm Elaeis guineensis Arecaceae palm
Dracaeana Dracaeana fragans Asparagaceae small tree
Sensitive Plant Mimosa pudica Fabaceae creeper
Calopo Calopogonium mucunoides Fabaceae creeper
 Green Summer Grass Urochloa decumbens Poaceae grass
Giant Bramble Rubus alceifolius Rosaceae scrambler
Snake Weed Stachytarpheta cayennensis Verbenaceae herb