Category Archives: New South Wales

Rehabilitation of former Snowy Scheme Sites in Kosciuszko National Park – UPDATE of EMR feature 2019.

Gabriel Wilks

Update of EMR feature – MacPhee, Elizabeth and Gabriel Wilks (2013) Rehabilitation of former Snowy Scheme Sites in Kosciuszko National Park.  Ecological Management & Restoration, 14:3, 159-171. Doi https://onlinelibrary.wiley.com/doi/10.1111/emr.12067

Key words.  Habitat construction, steep slopes, rock spoil.

Figure 1. Shaped rock spoil ready for planting more than 50 years after being dumped.

Introduction. Our original EMR feature article described the origins of this large, long-term rehabilitation program and the challenges faced in the first 10 years. The program’s aim was to address a range of impacts upon montane and sub-alpine vegetation and river corridors in Kosciuszko National Park from the Snowy Hydro Scheme, constructed from 1949 to 1974. Impacts included dumping of large volumes of rock spoil, loss of topsoil and native vegetation, introduction and spread of weeds and asbestos fragments in the landscape.  The article outlined the development of methodologies for restoration, particularly planting trials on steep rock spoils, and how obstacles such as slope instability, plant material availability and lack of soil were being overcome. The process of program implementation was given, including environmental and cultural heritage assessments undertaken as part of site works.  In 2013 a number of positive outcomes were already evident at the 200 sites that had been subjected to at least some treatment, including 18 sites where major rehabilitation works were undertaken. Outcomes included reduction in waterway impacts and invasive weeds, expansion of the Kosciuszko fauna database, regional community benefits, and production of an Australian Alps Rehabilitation Field Guide.

Further work. The Former Snowy Scheme Rehabilitation Program continues to reduce the long term environmental and safety risks of old degraded construction sites to Kosciuszko National Park, as well as improve their visual and ecological function. Some sites treated by 2013 have blended in with the surrounding landscape and are difficult to identify. Many sites are continuing to improve in condition over time, with distinct vegetation layers, natural plant recruitment and evidence of native fauna habitat. Construction history, rock spoil and loss of soil and plant species remain evident at highly altered sites, despite a high standard of rehabilitation work.

An additional 12 Major rehabilitation works have been undertaken since 2013, with selected signature projects and rehabilitation techniques described below.  Note that the former Snowy Scheme rehabilitation program does not address the impact of current Snowy Hydro Limited or proposed infrastructure and support networks such as powerlines, easements, river regulation or roads.

1. Rehabilitation of the Tooma–Tumut Access Tunnel Adit Spoil Dump. This spoil dump (Fig. 1) is located on the highly incised upper reaches of the Tumut River.  The spoil originates from construction in 1958-1961 of the Eucumbene–Tumut Tunnel, which transfers the headwaters of the Tooma River to Tumut Pond. Following earthworks in 2017, the planting crew successfully planted, watered, fertilised and mulched approximately 12,000 plants on rock spoil, with monitoring being undertaken by Greening Australia Capital Region staff (Fig 2.)

Figure 2. Year 1 Revegetation monitoring at Tooma-Tumut SD by Greening Australia Capital Region staff, 2018

2. Construction of contained habitat for the Southern Corroboree Frog. A series of remote enclosures (Fig 3) have been constructed in both rehabilitation areas and former habitat locations to enable re-introduction of this Critically Endangered species (Fig 4), following the devastating impacts of chytrid disease. These enclosures are developing essential stepping stones for frogs from captive breeding programs to move back into the wild. Design of enclosures requires ensuring self-sustaining food and water, shallow ponds for breeding, ability for Threatened Species staff to monitor and control disease and exclusion of other frogs. These works have been done in partnership with NSW Threatened Species staff and zoo institutions.

Figure 3. Constructing Southern Corroboree Frog enclosures in remote locations

Figure 4. Southern Corroboree Frogs living successfully back in Kosciuszko

3. First live record of Smoky Mouse in Kosciuszko National Park. The Smoky Mouse (Pseudomys fumeus Fig. 5) was found alive and well for the first time in Kosciuszko National Park, at a Happy Jacks rehabilitation site. Up until the discovery, the only currently known population of the small, smoky grey coloured mouse still surviving in NSW was in the Nullica area, NSW South Coast.  Three individuals, 2 males and 1 female were a significant find for survival and database records of this Critically Endangered Species, and a technical short note was published in EMR in 2017 by fauna surveyor Martin Schulz who found the animals.

Figure 5. A Happy Jacks Smoky Mouse.

4. Making people and places safer with rehabilitation. Sites that housed construction depots and townships during Snowy scheme construction still contained fragments of asbestos which were rapidly degrading due to weather exposure. As total removal was not feasible, the rehabilitation team worked with asbestos experts to develop practical measures to reduce public safety risks. At the remote Junction Shaft Contractors Camp (at Happy Jacks, Figs 6 and 7) and a former township and current camping ground at Island Bend a range of techniques were developed, delineation of zones for suitable uses, creating natural vegetation buffers and capping with rock spoil and plants.

Figure 6. The Junction Shaft Camp in 1955.

Figure 7. The same site 62 years later (and one year after works) with a range of capping and planting zones, including a heli-pad, Mountain Pygmy Possum habitat, and new plantings to improve safety and environment.

5.  Applying techniques beyond Kosci. Project team members took some winter time out of Kosciuszko to ‘grow’ a protection zone for a known population of Endangered Green and Golden Bell Frog (Litoria aurea) and constructed a series of ponds for future breeding in an old sand quarry at Worrigee Nature Reserve, Nowra (Fig 8). Given former quarries are a feature of a large infrastructure project such as the Snowy Scheme, the team had the technical knowledge for how to restore ecological function despite a radical departure from usual flora and fauna species. A range of techniques including neighborhood consultation, barrier logs and blocks, berms and vegetation were used to reduce the impact of recreational and unauthorised motorbikes and rubbish dumping.

Figure 8. Creating Bell Frog habitat in degraded borrow pits.

6. Growing rehabilitation resources and protecting karst ecosystems. The use of treated waste at the Yarrangobilly Caves visitor precinct to grow snow grasses (Poa spp.) for use in rehabilitation projects across Kosciuszko and been continued and developed (Fig. 9). A renewed emphasis on site production has enabled Poa seed to be available for other projects within the Park. This provides an ecologically preferable option for soil stabilisation and ground cover establishment, reducing the risk of weed invasion and dependence on sterile rye corn as the only available option.

Figure 9. Inspecting plants for seed harvest, which yielded 52 kgs of Poa seed in 2017.

Lessons Learned. It is clear that this is a unique rehabilitation project due to the large number of sites, the natural and heritage values of Kosciuszko National Park and the longevity and continuity of the commitment (approx. 20 years).  Understandably, however, at this point in time challenges in rehabilitation remain. ‘Off the shelf’ rehabilitation products are limited due to remoteness of locations, plant species required, Park management policies and required hygiene protocols. It is important that additional threats are not accidentally introduced, such as foreign pathogens and flora and fauna. As much as possible, resources such as coarse woody debris, woodchip, plant material and compost are sourced from within the Park. A flexible and dynamic approach to the very definition of rehabilitation and techniques and materials is required.  Specific lessons include the following.

Adding organic material on degraded sites is always beneficial. Rehabilitation success has been most obvious where logs, litter, woodchip and straw have been added to the site, to provide mico-niche climate, habitat, and improve soil. While this may increase short term management requirements such as weed control, the commitment is worth it due to the improved results.

Creating compost from old sawmill sawdust has worked well for this rehabilitation project. The most recent development however is in the use of organics waste and treated effluent from visitation facilities as a compost, and there is opportunity for this on-Park recycling to develop.

Other resources such as rice straw have become limited during periods of sustained drought and less rice production. This will remain a challenge into the future. The value of minimising ground cover loss, retaining natural soil characteristics and organic matter in situ and ensuring rapid rehabilitation after disturbance in future developments will become increasingly important for rehabilitation success.

Be creative with team skills and capacity. Problems such asbestos contaminant presence must be addressed for safety, but doesn’t mean walking away from the challenge. A degraded site may be the perfect place to develop species targeted habitat.  Seek expertise advice and consider a range of current and new solutions.

ContactGabriel Wilks, Senior Project Officer, NPWS Southern Ranges Services. PO Box 472, Tumut NSW 2720.  Email: Gabriel.Wilks@environment.nsw.gov.au

Eastern Suburbs Banksia Scrub: is fire the key to restoration? – UPDATE to EMR SUMMARY

Geoff Lambert, and Judy Lambert

[Update to EMR summary  – Geoff Lambert and Judy Lambert (2015) Progress with restoration and management of Eastern Suburbs Banksia Scrub on North Head, Sydney.  Ecological Management & Restoration, 16:2, 95-199. https://onlinelibrary.wiley.com/doi/10.1111/emr.12160]

Key Words. Banksia Scrub, North Head, Critically Endangered Ecological Community, Diversity.

Fig 1. Images of the same location over time, taken from “walk-through” photographic surveys (top to bottom) pre-fire, immediate post-fire and 5-years post-fire. (Photos Geoff Lambert)

Introduction. In the original feature, we reported on a number of projects related to the fire ecology of Eastern Suburbs Banksia Scrub (ESBS), also known as Coastal Sand Mantle Heath (S_HL03), located in conserved areas on North Head, Sydney Australia. Following a Hazard Reduction burn in September 2012, we examined changes in species numbers and diversity and compared these measures with control areas which had been thinned. We fenced one-third of the survey quadrats to test the effects of rabbit herbivory. There had been no fire in this area since 1951.

Twelve months after treatment, burned ESBS had more native plants, greater plant cover, more native species, greater species diversity and fewer weeds than did thinned ESBS (Fig 1). Areas that had been fenced after fire had “superior” attributes to unfenced areas. The results suggested that fire could be used to rejuvenate this heath and that this method produced superior results to thinning, but with a different species mix. Results of either method would be inferior were attempts not made to control predation by rabbits (See 2015 report).

Further works undertaken. In 2015 and 2017 we repeated the surveys, including photographic surveys on the same quadrats. Further Hazard Reduction burns were conducted, which provided an opportunity to repeat the studies reported in the 2015 feature. The study design of the burns was broadly similar to the earlier study, but rabbits were excluded by fencing four large “exclosures” over half the burn site. The pre-fire botanical survey was carried out in 2014, with logistical difficulties delaying the burn until late May 2018. Drought and other factors saw a post-fire survey delayed until October 2019. Photographic surveys of the quadrats have been completed.

Seven cm-resolution, six-weekly, aerial photography of North Head is regularly flown by Nearmap© (Fig 2). We use this photography to monitor the whole of the headland and, in particular, the various burn areas. In order to extrapolate from our quadrat-based sampling (usually 1% of a burn area), the University of Sydney flew 5mm-resolution UAV-based surveys on our behalf, on one of the 2012 burn areas and on the 2018 burn area in November 2017 (Fig 3) .

Apart from the fire studies, the general program of vegetation propagation and management has been continued by the Sydney Harbour Federation Trust and the North Head Sanctuary Foundation. The Australian Wildlife Conservancy has also undertaken a “whole of headland”, quadrat-based vegetation survey as the first stage of its “Ecological Health” rolling program for its sites.

Fig 2. Nearmap© site images (top to bottom) pre-fire, immediate post-fire and 7-years post-fire. (Photos Nearmap)

Further results. The original results suggested that fire could be used advantageously to rejuvenate ESBS and produced superior results to thinning. While subsequent photographic monitoring shows distinct vegetation change (Figs 1 and 2), on-ground monitoring showed that by five years after the fire we could no longer say this with any optimism. In summary:

  • In the immediate fire aftermath, there was vigorous growth of many species
  • Over the ensuing 5 years, plants began to compete for space, with many dropping out
  • Species diversity was high following the fire but then dropped below pre-fire levels
  • Some plants (e.g. Lepidosperma and Persoonia spp.) came to dominate via vegetative spread
  • The reed, Chordifex dimorphus has almost disappeared
  • Tea-trees (Leptospermum spp.) are gradually making a comeback
  • Between 2015 and 2017, ESBS species numbers were outpaced by non-ESBS species, but held their own in terms of ground cover.

The total disappearance of Chordifex (formerly an abundant species on North Head and prominent in the landscape) from fully-burned quadrats was not something that we could have predicted. This species is not in the Fire Response database, although some Restio spp. are known to be killed by fire. This contributes greatly to the visual changes in the landscape. The great proliferation of Lance Leaf Geebung (Persoonia lanceolata) has also changed the landscape amenity (Fig 1, bottom).

To summarise, the 2012 burn has not yet restored ESBS, but has produced a species mix which may or may not recover to a more typical ESBS assemblage with ongoing management over time. Given that the area had not been burned for 60 years, it may be decades before complete restoration.

Our further studies on the use of clearing and thinning on North Head as an alternative to fire (“Asset Protection Zone Programme”), indicates that thinning and planting can produce a vegetation community acceptable for asset protection fire management and potentially nearly as rich as unmanaged post-fire communities (Fig 4). It is necessary to actively manage these sites by removing fire-prone species every two years. In addition, a trial has been started to test whether total trimming of all except protected species to nearly ground level in an APZ, is an option for longer-term management.

Fig 3. “Thinning Experiment” fenced quadrat #3 in July 2019. The quadrat was created in 2013 by removing Coastal Teatree (Leptospermum laevigatum) and Tree Broom Heath (Monotoca elliptica). The experimental design is a test of raking and seeding, with each treatment in the longer rows. All non-endangered species plants were trimmed to 0.25 metres height in mid-2017. (Photo Geoff Lambert)

Lessons learned and future directions. It is too early to say whether we can maintain and/or restore North Head’s ESBS with a single fire. Further fires may be required. A similar conclusion has been drawn by the Centennial Parklands Trust, with its small-scale fire experiments on the York Road site. We need new and better spot- and broad-scale surveys and further burns in other areas on North Head over a longer period. The spring 2019 survey, just completed, offers an opportunity to better assess the notion that fire is beneficial and necessary.

It will be necessary to monitor the effects of future fires on ESBS diversity closely and for much longer than five years. More active management of the post-fire vegetation may be needed, as we have previously discussed in the feature, and as happens at Golf Club sites (also see video) .

The 2012 burn was relatively “cool”. There is some evidence that “hot” burns (such as have been carried out by NSW Fire and Rescue at some Eastern Suburbs golf courses) may produce improved restoration of ESBS. The 2018 burn on North Head was planned as a “hot” burn. This was not completely achieved, but we may be able to compare “hot” and “cool” burn patches within it.

Fig 4. A 2017 UAV image of quadrat 23 five years after the 2012 burn. The image has been rotated to show the quadrat aligned on the UTM grid. The red square shows the rabbit-proof fences; the black square shows the survey quadrat and the blue squares show the four 1×1 metre vegetation plots. The resolution is approximately 5 mm. (Photo University of Sydney Centre for Field Robotics)

Stakeholders. Sydney Harbour Federation Trust, North Head Sanctuary Foundation. Australian Wildlife Conservancy, NSW National Parks and Wildlife Service, Fire & Rescue NSW.

Funding Bodies. Foundation for National Parks & Wildlife [Grant No. 11.47], Sydney Harbour Federation Trust, Australian Wildlife Conservancy.

Contact Information. Dr G.A.Lambert, Secretary, North Head Sanctuary Foundation, (P.O.Box 896, BALGOWLAH 2093, Tel: +61 02 9949 3521, +61 0437 854 025, Email: G.Lambert@iinet.net.au. Web: https://www.northheadsanctuaryfoundation.org.au/

More than just a Long Paddock: Fostering native vegetation recovery in Riverina Travelling Stock Routes and Reserves – UPDATE of EMR feature

Ian Davidson

[Update of EMR feature – Davidson, Ian and Peter O’Shannassy (2017) More than just a Long Paddock: Fostering native vegetation recovery in Riverina Travelling Stock Routes and Reserves. Ecological Management & Restoration, 18:1, 4-14.  https://onlinelibrary.wiley.com/doi/10.1111/emr.12247]

Roger Harris with direct seeded shrubs –  Rand TSR. (Photo Ian Davidson)

Introduction.  As described in our 2017 EMR feature, the Enriching biodiversity in the NSW Riverina project was a five-year project funded by the Federal Government’s Carbon Farming initiative and managed by Murray Local Land Services (LLS). The project aimed to maintain the condition of the highest quality TSRs and improve the condition of 10% of all other TSRs, some of which had been receiving degrees of grazing management for many decades to optimize resilient native pastures (Refer to our earlier 2005, EMR feature). Given the NSW Riverina TSR network contains over 600 reserves, a sample was first selected for inspection to identify reserves with the potential for further active management. This led to the implementation of recommended land management and works on 109 reserves covering 13,558 ha and the subsequent monitoring of those reserves. Results indicated that, of these reserves, 70 had improved in vegetation condition by 2017. This project proved that large scale protection and improvement of TSR condition was possible using existing staff and provided valuable lessons that could be applied elsewhere across the state.

Table 1 Summary of key lessons learnt from the project and recommendations for effective TSR management

Human resources ·       Use existing knowledge where available

·       Maintain continuity of leadership

Assessment and

monitoring

·       Establish broadly applicable and consistent assessment and monitoring criteria

·       Use methods which are easily understood

·       Consider seasonal effects on the timing of surveys

·       Recommended actions should be appropriate for the site condition

Project Scale ·       Larger project areas and longer project timelines increase the rate of success

·       Regular monitoring avoids major problems

Revegetation ·       Seed banks are vital to achieving large scale revegetation

·       Multiple species should be used in direct seeding

·       Exotic grasses should be controlled prior to direct seeding

·       Native species can assist in spreading shrubs over time

Land Management ·       Controlling herbivores is critical during early growth stages

·       Grazing indicators/surrogates are useful

·       Stock type impacts grazing style

·       Cattle can graze areas with shrub seedling germination under certain conditions

·       Fencing and water points offer flexibility in managing stock for regeneration

·       Noisy Miners reduce small woodland bird numbers and they are difficult to control

Unplanned Impacts ·       Human intervention in unpredictable Natural events can lead to major changes in land management focus

Stuart Watson monitoring vegetation at Narrow Plains TSR. (Photo Ian Davidson)

Subsequent developments. Since the publication of our 2017 feature ‘More than just a Long Paddock: Fostering native vegetation recovery in Riverina Travelling Stock Routes and Reserves’ the following five key developments regarding nature conservation on TSRs in NSW have occurred.

  1. Developing and applying a simple field based consistent method for assessing and monitoring vegetation condition across the TSR network – A new rapid assessment and monitoring method was developed and trialed in this project for use by land managers with limited botanical and scientific skills and limited time. This field-based method known as Rapid Conservation Assessment Method (RAM) proved useful and has the potential for broader adoption across NSW. For detailed information refer to https://www.lls.nsw.gov.au/livestock/stock-routes/conservation-of-tsrs
  2. Categorizing the conservation status using an agreed method of TSRs across NSW – Using the RAM to complete assessments and collating all previously assessed TSR reports, LLS developed a consistent statewide map of the conservation status for the 534,000ha under their control (refer to https://www.lls.nsw.gov.au/livestock/stock-routes/conservation-of-tsr). This enabled LLS, the statewide land manager, to better understand the overall vegetation condition, extent and distribution of their TSR assets from a nature conservation perspective.
  3. Developing a Best environmental management practice (BeMP) Toolkit for TSRs to ensure good long-term conservation objectives – Key knowledge learnt from the Riverina project, LLS ranger’s knowledge and experience and existing literature influenced the development of the NSW Travelling Stock Reserves State Planning Framework 2016–21 (the Framework), which provides the framework for managing TSRs for conservation. A Best Environmental Management Practice (BeMP) toolkit was also prepared from this collation of knowledge to assist LLS deliver land management outcomes (including grazing, apiary, native seed collection, emergency response/refuge for livestock, threatened ecological communities and species, revegetation on TSRs, weed control, pest animal control, soil disturbance and drainage changes) consistent with the Framework. The BeMP is currently in draft form.
  4. Developing a statewide plan of management (PoM) for TSRs to ensure consistency across administrative boundaries – The NSW government is finalizing the details of a PoM which provides LLS staff, TSR stakeholders, investors, partners and customers with our shared vision and common mission. It sets out agreed strategies, approaches, principles and quality system to better manage the reserves. This PoM aims to improve social, economic, environmental and cultural outcomes while maintaining grazing as an important economic use and conservation tool. Importantly this plan establishes the need for shared responsibility and collaborative funding. For more information refer to https://www.lls.nsw.gov.au/__data/assets/pdf_file/0005/839930/NOV-TSR-PoM-MOedits-1.pdf
  5. Attracting significant investment to assist with protection and maintenance of TSR environmental values – LLS the managers of NSW TSRs receive no recurrent funding from government for the environmental management of the TSR estate and therefore have been dependent upon the proceeds from permits and leases e.g. grazing and annual grants e.g. weed and pest animal control to maintain the condition of TSRs. Now however, based on the PoM and guided by environmental management and works consistent with best environmental management practice, the LLS is negotiating with a government investor to fund agreed long term maintenance and enhancement of selected high and moderate conservation value TSRs.

Peter O’Shannassy with direct seeded shrubs on Snake Island TSR. (Photo Ian Davidson)

Lessons learned. Together, the five developments above show how the large-scale restoration project reported in 2017 has been further developed as a model for TSR protection and restoration across NSW, enabling buy-in by LLS to better manage these invaluable natural resource assets across NSW.

Acknowledgements. LLS staff Peter O’Shannassy steered most aspects of the project from its inception, whilst Stuart Watson and Roger Harris managed most of the on-ground management and works and lately Gary Rodda the Murray General Manager who has overseen the statewide development of the PoM. Lastly, I dedicate my TSR work to my great mate Rick Webster who was lost to us recently and with whom I shared a deep, long standing curiosity and love of these special areas.

Contact.  Ian Davidson (for technical matters) ian@regenerationsolutions.com.au  or  Peter O’Shannassy  (for land management and operational matters) peter.o’shannassy@lls.nsw.gov.au

 

 

 

 

 

 

Butterfly population persists 10 years after emergency habitat restoration and translocation – UPDATE to EMR feature

[Update to 2008 EMR feature  –  Raymond Mjadwesch and Simon Nally (2008) Emergency relocation of a Purple Copper Butterfly colony during roadworks: Successes and lessons learned. Ecological Management & Restoration,  9:2, 100-109.   https://doi.org/10.1111/j.1442-8903.2008.00400.x]

By Simon Nally and Raymond Mjadwesch

Fig 1.  The endangered Purple Copper Butterfly (Paralucia spinifera) (Photo Raymond Mjadwesch)

Key wordsParalucia spinifera, Purple Copper Butterfly, reintroduction, invertebrate, threatened species.

Introduction: As reported in the original EMR feature, the unintended destruction of the habitat of a population of the endangered Purple Copper Butterfly (Paralucia spinifera, Fig 1) north of Lithgow, Australia in 2004, precipitated a bold, innovative, and rapid emergency program of habitat restoration and butterfly larvae translocation.

A stand of the butterfly’s larval host plants, Blackthorn (Bursaria spinosa subsp. lasiophylla), had been largely destroyed to enable road construction (Fig 2a). The butterflies had commenced emerging from their nearly nine-month-long pupation in the attendant ant’s (Anonychomyrma itinerans) underground nests to find an absence of host plants.

Construction work ceased immediately, and supplementary Blackthorn plants were planted throughout the area of predicted butterfly emergence. The Blackthorn were planted in their pots, to allow for later removal and replanting in the area where the habitat was being restored.  The Blackthorn were sugar-baited to attract the attendant ant as the ant was assumed to affect the male butterfly’s selection of home ranges, and ultimately, egg-laying on these larval host plants. Concurrently with the provision of Blackthorn for egg-laying, an adjoining degraded area of potential habitat was treated for infestations of woody weeds and growth of emergent Eucalyptus trees that excluded Blackthorn or blocked sunlight, precluding its suitability for occupation by the species.  Once weeds were controlled, Blackthorn was established in this area using tube-stock planting.

Attendant ants were enticed to all the Blackthorn introduced to the site, male butterflies established territories and were successful at attracting females with whom to mate, and these females laid eggs on the Blackthorn. The project partners were relieved at these initial results! However, as much of the site was to be permanently destroyed due to road construction, this temporarily reprieved population had to be translocated.

Over 12 nights, 1,260 of the facultatively nocturnal larvae were collected (along with any associated attendant ants) as they emerged to feed on Blackthorn leaves and translocated to the newly created habitat established on an adjacent restoration area (Fig 2b). Each translocated larva was monitored until it was attended by ants (again attracted to the recipient habitat using a sugar bait). Further monitoring continued to confirm continued growth of larvae until pupation was assumed to occur.

The duration of the emergency habitat restoration and translocation activities from first discovery of the habitat destruction to the assumed pupation of the translocated larvae in the newly established habitat (Fig 3) was less than five months.

After the autumn and winter pupation period, the project partners were delighted to find butterflies emerging, mating, and laying eggs on the remaining restored habitat, one year after the initial habitat destruction was first detected. Monitoring of larval numbers during 2005-2008, which involved systematic nocturnal inspection of all Blackthorn plants at the site, indicated that the population was secure and had grown after an initial reduction in calculated numbers in the first year after translocation.

Figure 2a. 2004 – The site as found showing the extent of habitat destruction (when the butterfly and habitat loss was initially detected). (Photo Raymond Mjadwesch)

Figure 2b. 2005 – Larvae from yellow-delineated area were translocated (after temporary introduction) into the blue-delineated area and bushland further right. (Photo Raymond Mjadwesch)

Monitoring update: In 2013 and 2015 monitoring reverted to an area search method, counting flying butterflies – a technique routinely used to indicate butterfly distribution / areas of activity at each of the other known populations. In 2015, ten years after the emergency translocation and habitat restoration, 48 butterflies were observed in the restored habitat, the second highest number recorded for this site.

Note that the results of monitoring counts can vary with date of survey relative to the flying period, time of day, and weather conditions on the day, and represent an indicator of presence and activity rather than a measure of absolute abundance. During some years multiple monitoring events occurred; in 2013 and 2015 there was only a single monitoring count.

There have been no further nocturnal larvae counts since the culmination of the project.

A 2019 site assessment identified the need for further woody weed maintenance works (which has been ongoing in the interim, funded by the LLS) to avoid potential degradation of the habitat quality due to competition with and shading of the host plant, Blackthorn.  Longer term maintenance of this site may require active management to ensure persistence of Blackthorn either through burning or mechanical damage to Blackthorn to promote re-sprouting from the rootstock and juvenile leaf production. Juvenile leaves lack the hairy indumentum present on the lower surfaces of intermediate and adult Blackthorn leaves, and have been observed to be preferentially skeletonized by early-instar larvae.

The 2019 site inspection also revealed that powerline easement works had resulted in weedicide spraying of eucalypt (Eucalyptus ssp.) saplings throughout the restored habitat, with Blackthorn plants and other native plant species affected.

Figure 3a – the site in 2005, after restoration works were complete, showing the initial flush of pioneer species after soil disturbance and restoration. (Photo Raymond Mjadwesch)

Figure 3b – the site in 2019 showing the final shrubby understory of sedges and shrubs (including scattered Blackthorn) typical of the locally native open forest community. (Photo Raymond Mjadwesch)

Lessons learned and future directions: Several factors contributed to the success of the habitat restoration and translocation program, some of which were of notable serendipity. It was extremely fortunate that the species was detected within the affected area (after the initial survey of the site had failed to detect habitat for the species); that Blackthorn tube-stock (upon which the restoration relied) was available; that an area considered likely to support Purple Copper Butterfly suitable for rehabilitation lay adjacent to the affected area; and that the timing of the damage in the annual lifecycle of the species allowed the partners to work with the opportunity to establish larval food plants  when it was required.

However, we believe that it was human factors that fundamentally combined to create the environment for success:

  • the commitment of the NSW Roads and Maritime Services (then the RTA) to immediately and fully support restoration works to ameliorate the damage and maximize the chances of the population surviving in the long term, including changing the design of the works to reduce the extent of permanent damage, and the funding of the restoration, translocation, and monitoring activities.
  • the project partners, including the authors, the RTA, NSW National Parks and Wildlife Service, Australian Trust for Conservation Volunteers, and Lithgow LandCare unified in collaboration, ceasing other activities to direct all necessary effort to maximize chances of success.
  • the quick, resourceful and bold action to trial and implement innovative techniques that were risky and speculative, such as luring attendant ants to planted Blackthorn using sugar, trial translocating attendant ants, and translocating larvae.
  • that there had been sufficient field observations to  predict the likely behavior of butterflies and larvae and to predict the likely response of the species’ habitat to management intervention.

We encourage restoration practitioners to immerse themselves in the environments they intend to manipulate, and ponder on the behavior, function, and interactions between each element of the ecosystem before them. When choosing to act – to intervene – to manipulate, do so sensitively to what you both know and feel that you have learned in the field, and act decisively, quickly, and boldly. Most importantly, corral a team of partners who believe in the endeavor and who fully commit their support to each other for a common restoration objective.

Endnote: In September 2019, an unplanned fire burnt much of the site. Given the monitoring data available for this site, further monitoring to study the effect of fire on the species and its habitat is being considered.

 Stakeholders and Funding bodies:   NSW Roads and Traffic Authority (now NSW Roads and Maritime), NSW National Parks and Wildlife Service (now NSW Office of Environment and Heritage), Australian Trust for Conservation Volunteers, Lithgow LandCare, Australian Government Department of Environment and Energy

Contact information: Simon Nally, 8 Gurney Place PAGE ACT, Australia, Tel: +61 407870234, Email: suseandsimon@bigpond.com. Ray Mjadwesch, Mjadwesch Environmental Service and Support, 26 Keppel Street, Bathurst, NSW 2795 Australia, Tel: +61 423949789, Email:  ray@mjadweschenvironmental.com.au

Ku-ring-gai Flying-fox Reserve Habitat Restoration Project at Gordon, 2000 – 2019 UPDATE of EMR feature

Nancy Pallin

[Update to EMR feature –  Pallin, Nancy (2001) Ku-ring-gai Flying-fox Reserve Habitat restoration project, 15 years on.  Ecological Management & Restoration 1:1, 10-20.  https://onlinelibrary.wiley.com/doi/10.1111/emr.12229]

Key words:         bush regeneration, community engagement, wallaby browsing, heat events, climate change

Figure 1. Habitat restoration areas at Ku-ring-gai Flying-fox Reserve within the urban area of Gordon, showing areas treated during the various phases of the project. Post-2000 works included follow up in all zones, the new acquisition area, the pile burn site, the ecological hot burn site and sites where vines have been targeted. (Map provided by Ku-ring-gai Council.)

Introduction. The aim of this habitat restoration project remains to provide self-perpetuating indigenous roosting habitat for Grey-headed Flying-fox (Pteropus poliocephalus) located at Ku-ring-gai Flying-fox Reserve in Gordon, NSW Australia (Fig 1).  The secondary aim was to retain the diversity of fauna and flora within the Flying-fox Reserve managed by Ku-ring-gai Council. Prior to works, weed vines and the activity of flying-foxes in the trees had damaged the canopy trees while dense weed beneath prevented germination and growth of replacement trees.  Without intervention the forest was unable to recover.  Natural regeneration was assisted by works carried out by Bushcare volunteers and Council’s contract bush regeneration team.  The work involved weed removal, pile burns and planting of additional canopy trees including Sydney Bluegum (Eucalyptus saligna), which was expected to cope better with the increased nutrients brought in by flying-foxes.

Figure 2. The changing extent of the Grey-headed Flying-fox camp from the start of the project, including updates since 2000. (Data provided by KBCS and Ku-ring-gai Council)

Significant changes have occurred for flying-foxes and in the Reserve in the last 20 years.

In 2001 Grey-headed Flying-fox was added to the threatened species lists, of both NSW and Commonwealth legislation, in the Vulnerable category.  Monthly monitoring of the number of flying-foxes occupying the Reserve  has continued monthly since 1994 and, along with mapping of the extent of the camp, is recorded on Ku-ring-gai Council’s Geographical Information System. Quarterly population estimates contribute to the National Monitoring Program to estimate the population of Grey-headed Flying-fox.  In terms of results of the monitoring, the trend in the fly-out counts at Gordon shows a slight decline.  Since the extreme weather event in 2010, more camps have formed in the Sydney basin in response to declining food resources.

In 2007, prompted by Ku-ring-gai Bat Conservation Society (KBCS), the size of the Reserve was increased by 4.3 ha by NSW Government acquisition and transfer to Council of privately owned bushland. The Voluntary Conservation Agreement that had previously established over the whole reserve in 1998 was then extended to cover the new area.   These conservation measures have avoided new development projecting into the valley.

From 2009 Grey-headed Flying-fox again shifted their camp northwards into a narrow gully between houses (Fig 2).  This led to human-wildlife conflict over noise and smell especially during the mating season. Council responded by updating the Reserve Management Plan to increase focus on the needs of adjoining residents.  Council removed and trimmed some trees which were very close to houses. In 2018 the NSW Government, through Local Governments, provided grants for home retrofitting such as double glazing, to help residents live more comfortably near flying-fox camps.

Heat stress has caused flying-fox deaths in the Reserve on five days since 2002. Deaths (358) recorded in 2013, almost all were juveniles of that year.  KBCS installed a weather station (Davis Instruments Vantage Pro Plus, connected through a Davis Vantage Connect 3G system) and data loggers to provide continuous recording of temperature and humidity within the camp and along Stoney Creek.  The station updates every 15 minutes and gives accurate information on conditions actually being experienced in the camp by the flying-foxes. The data is publicly available http://sydneybats.org.au/ku-ring-gai-flying-fox-reserve/weather-in-the-reserve/Following advice on the location and area of flying-fox roosting habitat and refuge areas on days of extremely high temperatures (Fig 3.) by specialist biologist Dr Peggy Eby, Council adopted the Ku-ring-gai Flying-fox Reserve 10 Year Management and Roosting Habitat Plan in 2018.  Restoration efforts are now focused on improving habitat along the lower valley slopes to encourage flying-foxes to move away from residential property and to increase their resilience to heat events which are predicted to increase with climate change.

Figure 3. Map showing the general distribution of flying-foxes during heat events, as well as the location of exclosures. (Map provided by Ku-ring-gai Council)

Further works undertaken.  By 2000 native ground covers and shrubs were replacing the weeds that had been removed by the regeneration teams and Bushcare volunteers.  However, from 2004, browsing by the Swamp Wallaby (Wallabia bicolor) was preventing growth of young trees and shrubs.  Bushcare volunteers, supported by KBCS and Council responded by building tree cages made from plastic-mesh and wooden stakes. Reinforcing-steel rods replaced wooden stakes in 2008.   From 2011, the Bushcare volunteers experimented with building wallaby exclosures, to allow patches of shrubs and groundcovers to recover between trees (Figs 3 and 4).  Nineteen wallaby exclosures have been built. These range in size from 7m2 to 225m2 with a total area of 846m2.   Wire fencing panels (Mallee Mesh Sapling Guard 1200 x 1500mm) replaced plastic mesh in 2018.  Silt fence is used on the lower 0.5m to prevent reptiles being trapped and horizontally to deter Brush Turkey (‎Alectura lathami) from digging under the fence.

The wallaby exclosures have also provided an opportunity to improve moisture retention at ground level to help protect the Grey-headed Flying-fox during heat events.  While weed is controlled in the exclosures south of Stoney Creek, those north of the creek retain Trad and privets, consistent with the 10 Year Management and Roosting Habitat Plan.

Madeira Vine (Anredera cordifolia) remained a threat to canopy trees along Stoney Creek for some years after 2000, despite early treatments.  The contract bush regen team employed sInce 2010 targeted 21 Madiera Vine incursions.

A very hot ecological burn was undertaken in 2017 by Council in order to stimulate germination of soil stored seed and regenerate the Plant Community Type (PCT) – Smooth-barked Apple-Turpentine-Blackbutt tall open forest on enriched sandstone slopes and gullies of the Sydney region (PCT 1841).  This area was subsequently fenced. The contract bush regeneration team was also employed for this work to maintain and monitor the regeneration in the eco-burn area (720 hours per year for both the fire and Madiera Vine combined).

Figure 4. Exclusion fence construction method. Pictured are Bushcare volunteers, Jill Green and Pierre Vignal. (Photo N Pallin).

Figure 5. Natural regeneration in 2018 in (unburnt) exclosure S-6 (including germination of Turpentines). (Photo N. Pallin)

Further results to date. The original canopy trees in Phase 1 and Phase 2 (1987 -1997) areas have recovered and canopy gaps are now mostly closed. Circumference at breast height measurements were taken for seven planted Sydney Blue gum trees.  These ranged from 710 to 1410mm with estimated canopy spread from 2 to 6m.  While original Turpentine (Syncarpia glomulifera) had circumferences from 1070 and 2350mm with canopy spread estimated between 5and 8m, those planted or naturally germinated now have circumference measurements between 420 and 980mm with canopy spread estimated from 1.5 to 3m.  A Red Ash (Alphitonia excelsa) which naturally germinated after initial clearing of weeds now has a circumference of 1250mm with a canopy spread of 5m.  Also three Pigeonberry Ash (Elaeocarpus kirtonii) have circumference from 265 to 405mm with small canopies of 1 to 2m as they are under the canopies of large, old Turpentines.  As predicted by Robin Buchanan in 1985 few Blackbutt (Eucalyptus pilularis) juveniles survived while the original large old trees have recovered and the Sydney Bluegum trees have thrived.

In the Phase 3 (1998 – 2000) area south of Stoney Creek the planted Sydney Blue Gum now have circumferences measuring between 368 and 743 (n7) with canopy spread between 2 and 6 m.  in this area the original large trees have girths between 1125 and 1770mm (n7) whereas trees which either germinated naturally or were planted now range from 130 to 678mm (n12).  These measurement samples show that it takes many decades for trees to reach their full size and be able to support a flying-fox camp.

Wallaby exclosures constructed since 2013 south of Stoney Creek contain both planted and regenerated species.  Eight tree species, 11 midstorey species, 27 understorey species and eight vines have naturally regenerated.  Turpentines grew slowly, reaching 1.5m in 4 years.  Blackbutts thrived initially but have since died. In exclosures north of the creek,  weeds including Large-leaved Privet,  Ligustrum lucidum,  Small-leaved privet,  L. sinense,  Lantana, Lantana camara,  and Trad, Tradescantia fluminensis) have been allow to persist and develop to maximise ground moisture levels for flying-foxes during heat events. Outside the exclosures, as wallabies have grazed and browsed natives, the forest has gradually lost its lower structural layers, a difference very evident in Fig 6.

Figure 6. Visible difference in density and height of ground cover north and south of Stoney creek. (Photo P. Vignal)

Coachwood (Ceratopetalum apetalum) were densely planted in a 3 x 15m exclosure under the canopies of mature Coachwood next to Stoney Creek in 2015. In 4 years they have reached 1.5m.  In this moist site native groundcovers are developing a dense, moist ground cover.

Madiera Vine, the highest-threat weed, is now largely confined to degraded edges of the reserve, where strategic consolidation is being implemented with a view to total eradication.

In the hot burn area, which was both fenced and weeded, recruitment has been outstanding. One 20 x 20m quadrat recorded 58 native species regenerating where previously 16 main weed species and only 6 native species were present above ground. A total of 20 saplings and 43 seedlings of canopy species including Eucalyptus spp., Turpentine and Coachwood were recorded in this quadrat where the treatment involved weed removal, burning and fencing  (S. Brown, Ku-ring-gai Council, July 2019, unpublished data).  Unfortunately, however, the timing and location of the burn did not take into account its impact on the flying-fox camp and there was some damage to existing canopy trees. It will be many years before the canopy trees, which are regenerating, will be strong enough to support flying-foxes.

Monitoring from the weather station and data loggers has shown that close to Stoney Creek on a hot day it is typically 2-3° C cooler, and 5-10% higher in humidity, than in the current camp area (pers. comm. Tim Pearson). During heat events the flying-foxes move to this cooler and moister zone, increasing their chances of survival.

Fauna observed other than flying-foxes includes a pair of Wedge-tail Eagle ( Aquila audax plus their juvenile, a nesting Grey Goshawk (Accipiter novaehollandiae) and a Pacific Baza (Aviceda subcristata).  Powerful Owl (Ninox strenua) individuals continue to use the valley. The presence of raptors and owls indicate that the ecosystem processes appear to be functional. Despite the decline of the shrub layer outside fenced areas, the same range of small bird species (as seen prior to 2000) are still seen including migrants such as Rufous Fantail ( Rhipidura rufifrons) which prefers dense, shady vegetation. The first sighting of a Noisy Pitta (Pitta versicolor) was in 2014.  Long-nosed Bandicoot (Perameles nasuta) individuals appear and disappear, while Swamp Wallaby remains plentiful.

Lessons learned and future directions. Climate change is an increasing threat to Pteropus species. On the advice of Dr Eby, Flying-fox Consultant, Council, KBCS and Bushcare Volunteers agreed to retain all vegetation including weeds such as Large-leaved Privet and Small-leaved Privet, patches of the shrub Ochna (Ochna serrulata) and Trad as a moist ground cover in the camp area and areas used by the flying-foxes during heat events.

Building cheap, lightweight fencing can be effective against wallaby impacts, provided it is regularly inspected and repaired after damage caused by falling branches. This style of fencing has the additional advantage of being removable and reusable.  It has been proposed that, to provide understory vegetation to fuel future burns in parts of the reserve away from the flying-fox camp, further such temporary fencing could be installed.

Ku-ring-gai Council has commenced a  program to install permanent monitoring points to annually record changes in the vegetation, consistent with the state-based  Biodiversity Assessment Method.

Stakeholders and Funding bodies. Members of KBCS make donations, volunteer for monthly flyout counts, Bushcare and present educational events with live flying-foxes. KBCS hosts the website www.sydneybats.org.au. Ku-ring-gai Council which is responsible for the Reserve has been active in improving management to benefit both residents and flying-foxes.  Ku-ring-gai Environmental Levy Grants to KBCS have contributed substantially to purchase of fencing materials and the weather station. http://www.kmc.nsw.gov.au/About_Ku-ring-gai/Land_and_surrounds/Local_wildlife/Native_species_profiles/Grey-headed_flying-fox

Thank you to Jacob Sife and Chelsea Hankin at Ku-ring-gai Council for preparing the maps and to volunteer Pierre Vignal for assistance with tree measurements, downloading data loggers and a photo.  Researcher,  Tim Pearson installed the weather station.

Contact information. Nancy Pallin, Management Committee member, Ku-ring-gai Bat Conservation Society Inc.  PO Box 607, Gordon 2072  Tel 61 418748109. Email:  pallinnancy@gmail.com

Ecological restoration and rehabilitation at Sydney Olympic Park – UPDATE to EMR feature

Jennifer O’Meara and Kerry Darcovich

[Update to EMR feature – O’Meara, Jennifer and Kerry Darcovich (2015) Twelve years on: Ecological restoration and rehabilitation at Sydney Olympic Park, Ecological Management & Restoration, 16:1, 14-28. https://onlinelibrary.wiley.com/doi/10.1111/emr.12150 ]

Keywords: Environmental management, ecological management, threatened species, Habitat management , woodland birds, Green and Golden Bell Frog

Introduction. The 2015 EMR feature described ecological restoration and management works at Sydney Olympic Park, a large urban park containing both remnant and constructed landscapes that underwent significant restoration in preparation for the 2000 Olympic Games. Sydney Olympic Park supports a rich natural environment that includes over 250 native animal species, over 400 native plant species and three endangered ecological communities.  The high ecological values of the Park have resulted in 304 hectares (nearly half of the Park) being zoned under NSW planning legislation for environmental conservation and management.  Key habitats include estuarine and freshwater wetlands, remnant eucalypt forest, saltmarsh meadows and woodland bird habitats.

The Park’s biodiversity is of high conservation significance, and makes a significant contribution to the social and economic values of the Park.  The Park’s natural environments enrich visitor experience, provide a living classroom for environmental education programs, and attract businesses and residents seeking proximity to nature. This project began in 2000 when management transferred from a construction phase after the Sydney Olympic Games to an active management phase and is supported by an extensive long term ecological monitoring program. This update summarises new works and outcomes since 2016.

Further works undertaken. The introduction of new ecological infrastructure for frog habitat targets threatening processes of predation by introduced fish and increasing water availability.  Fish-proof fences have been introduced to wetlands where the predatory fish Gambusia (Gambusia holbrooki) is present in Green and Golden Bell Frog (Litoria aurea) habitat (Fig 1). The fences are placed around ponds or pond clusters and then the pond is dried out and refilled with fish-free water. Constructed of sediment fences 600mm high and embedded in the ground, these fences stretch to a maximum of 200m and have successfully restricted the fish from ponds for more than three years.

Figure 1.  Gambusia fence

In order to reduce the impact of bird predation on tadpoles in key breeding ponds, bird netting secured by wire cables to the ground and supported by hoops has been introduced.  The netting is also used as a response to the sighting of Green and Golden Bell Frog tadpoles in ponds with Sydney Olympic Park staff deploying temporary netting where successful breeding has occurred. Netting is left on the pond until all metamorphs have dispersed from the pond then removed.

Restoration of the water-holding capacity and connectivity of bell frog habitat in the Brickpit and Kronos Hill has been improved with temporary ponds being created with tarps (Fig 2). The aim is twofold – to extend the number of predator-free, drought refuges, important for adult female frogs and metamorphs and to ensure frog corridors maintain connectivity.  More than 10 tarp ponds have been created and have an expected life span of 3-6 years and are very budget friendly. Annual monitoring has shown a remarkable uptake of these ponds by the Green and Golden Bell Frog.

Figure 2.  Tarp pond with netting

Further results to date. The Parks ecological monitoring program is ongoing and now entering the 16th consecutive year for birds, 15th for reptiles and 21 years for the Green and Golden Bell Frog. In 2018-19 the fourth woodland bird survey was completed, a four yearly assessment of the status of woodland birds and vegetation management at Sydney Olympic Park. Fifteen quadrats are surveyed over the spring and autumn seasons to measure bird communities which is then compared to change in vegetation structure. Results show that small birds were strongly, positively correlated with shrub cover, but strongly negatively correlated with tree cover and Noisy Miner (Manorina melanocephala).  Since 2006, Sydney Olympic Park Authority has implemented a habitat modification program aimed at increasing the structural diversity and complexity of key areas of the Park to support woodland birds. The program seeks to build connectivity between key woodland bird habitats with the form of habitat enhancement varying depending on site characteristics. The survey shows that this program is successfully creating suitable habitat for this group of birds.

With the prospect of greater demands by the public to access the Park at all hours (see below), Sydney Olympic Park staff have recently collected baseline light level readings from across the Park to inform decision making.  Data on lux levels and light source was collected from over 160 sites ranging from car parks to mangrove creeks. The main drive of the survey was to collect information on light spill into sensitive habitat areas where darkness is a key ecological feature. The survey led to a review of lighting and identification of where lights could be switched off or timed to decrease light impacts. The findings will also inform future planning for illumination within the Park.

Lessons learned and future directions. Sydney Olympic Park is part of a rapidly densifying area with the 30,000 residents currently located within a 3km radius forecast to increase to approximately 100,000 in ten years. Due to the density of housing, Sydney Olympic Park will be/is already the local park for this community, leading to increasing demand for recreation and access to the Parklands. This presents great opportunities for more people to connect with nature and to incorporate community education and sustainability into Park programs.  A new program known as Park Care has been launched recently and currently rolls out community clean up and revegetation activities.

The flipside of this rapid population increase is increasing risk of disturbance to ecologically sensitive areas which needs to be considered and mitigated carefully as the Park continues to evolve. Ensuring the Park is able to sustainably meet this demand is a focus for management now and into the future. New habitat management plans for ecologically sensitive areas of the Park are being developed to better-guide biodiversity conservation on a precinct level. Ongoing ecological management works, and managing the impacts of human disturbance, will be essential to conserving the ecological values of the Park.

Contact. Jennifer O’Meara, Parklands Ecologist, Sydney Olympic Park Authority, 5 Olympic Boulevard, Sydney Olympic Park 2127 NSW, Australia. Email: Jenny.omeara@sopa.nsw.gov.au

Restoration of Wollongong’s Tom Thumb Lagoon 25 Years On: UPDATE of EMR feature.

 Nicholas Gill

[Update of EMR feature: Gill, Nicholas (2005) Slag, steel and swamp: Perceptions of restoration of an urban coastal saltmarsh. Ecological Management & Restoration, 6:2, 85-93 https://onlinelibrary.wiley.com/doi/10.1111/j.1442-8903.2005.00224.x]

Keywords. coastal wetlands, urban green space, pollution, mangroves, volunteers.

Figure 1. Tom Thumb Lagoon and Greenhouse Park (a) 2008 and (b) 2017. (Source Google Earth)

Introduction. The 2005 feature was drawn from restoration work my students and I became involved in during the early 2000s at Tom Thumb Lagoon (TTL) – an estuarine wetland close to Wollongong’s CBD and adjacent to the Port Kembla industrial area and harbour. By that point Wollongong City Council (WCC), the Bushcare group Friends of Tom Thumb Lagoon (FTTL), industry, Conservation Volunteers Australia (CVA), and many volunteers had been variously working on the site since the early 1990s. After decades of impacts from industrial development, waste disposal, and neglect, this significant restoration effort encompassed removing landfill, reshaping the wetland with channels and shallow benches, revegetation, weeding, and the construction of access and viewing points. By the time we became involved and I wrote the 2005 paper, TTL and the adjacent Greenhouse Park (GHP; Fig 1), were substantially revegetated, aesthetically improved, and the saltmarsh wetlands were seen as ecologically valuable. Participants and stakeholders in the restoration project perceived that substantial progress and improvement had been made. They also perceived, however, that the project suffered from some issues common to such endeavours such as a lack strategic planning and monitoring of ecological outcomes.

Since this time, restoration and other work has continued at TTL and at GHP. The story of what has happened, however, is one of the dynamic and contextual nature of sites such as this. This is true in a biophysical sense of ongoing vegetation change, particularly the spread of Grey Mangrove (Avicenna marina), a native plant previously not occurring on the site but planted for perceived environmental benefits either in the 1990s, or around 2000. This spread (into what was previously saltmarsh and mudflats) arises from past decisions and, while providing benefits, is now potentially causing new problems as well as continuing debates about choices in restoration.  The social context has also been dynamic and influential, as priorities have shifted, as the funding environment has altered, and as the people and groups involved have changed. Finally, Tom Thumb Lagoon remains affected by the legacy of the industrial history of its location. Past waste disposal practices in the absence of regulation have led to pollution problems that have become of greater concern since the early 2000s.

Activities at Tom Thumb Lagoon and Greenhouse Park Today. The wetland area itself is adjacent to a capped waste disposal site that operated from the 1940s until the mid-1970s. This area is known now as Greenhouse Park and is being managed and developed as urban green space with more focus on fostering urban sustainability practices; any restoration work is nested within these foci. TTL and GHP were always associated through overlap between FTTL and GHP staff, and GHP facilities were a base for TTL activities. Today, however, personnel have changed, FTTL no longer exists and its key members are no longer associated with TTL, and TTL/GHP are managed as one site to a greater extent. The result of these factors, and of the achievements already made at TTL, have been a shift towards an emphasis on activities at GHP and a change in TTL activities from active restoration to maintenance. It is now GHP volunteers and associated WCC staff who undertake and oversee work at TTL. At GHP WCC has expended considerable resources in tree planting and expanding a permaculture garden. There is a shelter, outdoor kitchen, and pizza oven for volunteers, WCC and Wollongong firms compost green and food waste, and there are hopes for public, tourism, and event use. Around ten volunteers work at the site weekly. For the GHP staff and volunteers, activities at TTL itself today are largely limited to weeding, picking up litter, and feral animal control. Weeds and litter remain problems, partly due to TTL’s location at the bottom of an urban catchment. In addition, since 2005, frog ponds were installed at the eastern end of TTL for the endangered Green and Golden Bell frog (Litoria aurea), however, it is not clear if the ponds are effective. The non-native Giant Reed (Arundo donax) also remains well established at this end of TTL despite control attempts.

Shifts in support have meant that CVA bowed out of work at TTL/GHP in 2012. Previously their involvement had been via a wetlands program that relied on support from both industry (including Bluescope and NSW Ports, both operating adjacent to TTL) and government programs. Until 2012, in conjunction with WCC, CVA were revegetating the southern slopes of GHP (marked A in Fig. 1) and were removing weeds and litter from the saltmarsh. However, the funding that CVA relied on declined such that CVA was unable to continue at TTL/GHP.

Figure 2.  Eastern end of TTL looking south (a) 2002 and (b) 2019 (Photos Nick Gill)

The Mangroves are Coming. Apart from further revegetation at GHP, the most significant vegetation change at TTL has been the spread of Grey Mangrove. While approval to thin this species has been obtained in the past and some thinning did occur, it has not mitigated their current spread and density. Grey Mangrove spread is clearly seen for the period from 2002 to 2019 in Fig 2 which shows the eastern end of TTL and the southern end of the channel known as Gurungaty Waterway. Aerial photos further reveal changes from 2008-2017 where the largely east-west spread of mangroves along channels in TTL can be seen (marked B in Fig 1). Significant spread can also be seen north-south spread along Gurungaty Waterway over this period (marked C in Fig 1). As the 2005 paper records, not long after Grey Mangrove was planted in the late 20th or early 21st Century, its expansion was  soon causing concern for its consequences for the site’s mudflats, saltmarsh and tidal habitats although it appears to have largely remained confined to the channels and has no doubt generated some environmental benefits. In terms of its consequences on bird habitat, the long observations of local birdwatchers suggest that the expansion of Grey Mangrove has reduced the incidence of waders and shorebirds, particularly Black Winged Stilts (Himantopus himantopus) and also waterfowl and herons. Nonetheless, observers report that Grey  Mangrove colonisation is providing habitat for other birds, such as the Sacred Kingfisher (Todiramphus sanctus), the Nankeen Night-Heron (Nycticorax caledonicus), and the Striated Heron (Butorides striata). Elsewhere across more upland areas of TTL and GHP, the expansion of tree planting across GHP and TTL has seen a shift to birds favouring woodland habitats.

The expansion of Grey Mangrove is also implicated in flood risk, especially for the catchment of Gurungaty Waterway. A 2019 review of the Wollongong City Flood Study, suggests that low elevations and channel infrastructure, combined with sedimentation and flow limitations associated with the now dense mangroves (Fig. 3), have increased the likelihood of flooding in the urban catchment.

Figure 3.  Southern Gurangaty Waterway in (a) 2002 and (b) 2019. Note the steel footbridge on left of each photo. (Photos Nick Gill)

Industrial Legacies. The 2005 paper notes that saltmarsh restoration was an important part of the TTL work and that stakeholders saw the saltmarsh as a significant ecological element of TTL. Since 2004 coastal saltmarsh has been listed as an Endangered Ecological Community in NSW. From 2006, saltmarsh degradation prompted WCC to monitor the saltmarsh and analyse groundwater and soils.  This showed that the degradation was likely associated with ammonia leaching from the tip and causing nitrate pollution, and also with a hydrophilic layer of iron hydroxide in the soil causing waterlogging and contaminant absorption. The possible origins of this layer include past waste disposal practices from metal manufacturing.

These, however, are not the only legacies of past unregulated waste disposal and industrial activity. TTL is now a declared site of ‘significantly contaminated land’ by the NSW EPA. The 2018 declaration notes that site is contaminated by ‘polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons and other mixed contaminants from multiple sources including coal tar and lubricant oils’. At TTL elements of these can be visible as a film on the water surface and are among the substances leaching from GHP. Such substances are carcinogenic and exposure can cause a range of health problems. The presence of these materials in the groundwater has been known since the 1990s but from 2013 WCC began to monitor and map these materials. Monitoring points were installed along the wetlands at base of the old tip. Various remediation options for these contaminants, as well as for the nitrates and iron hydroxide layer, were proposed but action was not taken at this time for various reasons including disruption to the wetland, costs, and uncertainties regarding pollutant interception. As of 2019, the site is subject to a ‘Voluntary Management Proposal’ by WCC which includes the preparation of a remediation action plan by late 2019.

Future Directions. The last fifteen years have seen some aspects of restoration, such as tree planting, proceed and expand. By some measures this is continued progress of the original project. TTL/GHP is now a well-established urban green space with environmental and amenity value. However, concerns from the early 2000s about volunteer succession, the absence of a catchment approach to management, and the need to think more strategically about ecological trade-offs between management options have been realised to some extent. The spread of Grey Mangrove is the clearest example of this. In part, some of this is perhaps inevitable for a site with the history and setting of TTL/GHP; the management context has changed, participants and stakeholders have changed, and difficult legacy issues have assumed greater prominence and cost. Nonetheless, the challenge to manage the site with a clear strategy and goals remains.

Acknowledgements: For assistance with this update, I am indebted to several past and present WCC staff, particularly Mike McKeon. I was also helped by Adam Woods, formerly of CVA, and birdwatchers Penny Potter, Terrill Nordstrom, and David Winterbottom.

Contact. Nicholas Gill, School of Geography and Sustainable Communities Faculty of Social Sciences, University of Wollongong NSW 2522 Australia, Email: ngill@uow.edu.au

The biodiversity benefits of Greening Australia’s Saltshaker Project, Boorowa, NSW – UPDATE of EMR feature

David Freudenberger, Graeme Fifield, Nicki Taws, Angela Cailiss and Lori Gould

[Update of EMR feature – Freudenberger, David, Judith Harvey and Alex Drew (2004) Predicting the biodiversity benefits of the Saltshaker Project, Boorowa, NSW. Ecological Management & Restoration, 5:1, 5-14. https://doi.org/10.1111/j.1442-8903.2004.00176.x]

Key words: woodland restoration, monitoring, farmland rehabilitation, community engagement

Figure 1. Boorowa River Recovery project sites, south eastern NSW.

Introduction

The Boorowa catchment in central NSW, like most of the wheat-sheep belt of eastern Australia, has been extensively cleared for agriculture.  Remnant woodland cover is less than 10% and highly fragmented into small patches, often less than 20 ha. As described in the 2004 article, there has been a documented decline in biodiversity across this region linked to declines in landscape function including dryland salinity and eucalypt dieback. In response to these declines, farmers in this catchment have been involved in land rehabilitation projects for over 25 years.  Many of these projects have been facilitated by Greening Australia, a national non-governmental organisation focused on protecting and restoring native vegetation.  Pioneering projects in the 1990s were often small in scale and lacked landscape scale targets.  To address this, Greening Australia collaborated with CSIRO to develop guidelines for catchment scale “enhancement activities” for the $1.8 Million “Saltshaker Project” that carried out ground works as described in Box 1 of the 2004 article (reproduced below). The project was based on a $845,000 grant from the Australian Government’s Natural Heritage Trust program and $1 Million in in-kind support from farmers, the Boorowa Shire, Boorowa Landcare and Greening Australia. This project ran for just two years (2000-2002), but it was hoped that the project would provide strategic guidance for decades to come.  This appears to be the case.

 Box 1. Priority ‘enhancement activities
1. Protect existing remnant vegetation by fencing out domestic livestock with a priority to protect 10 ha or larger remnants in the best condition (complex understorey).
2. Establish native understorey plants in those protected remnants requiring enhancement of habitat complexity.
3. Enlarge existing remnants to at least 10 ha.
4. Create linkages between fenced remnants and other protected remnants. Linkages should be at least 25 m wide, or 10 ha stepping-stones, particularly in those areas more than 1.5 km from other patches 10 ha in size.
5. Fencing and revegetation of at least 50 m wide along creeks and flow lines.
6. In recharge areas, revegetate in 2-ha blocks, or greater than eight row strips to intercept deep soil water moving down-slope.
7. Revegetate areas mapped as having a high risk of dryland salinity.
8. Block plantings in discharge areas with links to other saline reclamation works.

(Box reproduced with permission from the original feature]

During the Saltshaker project, bird surveys were conducted within 54 discrete patches of remnant woodland.  Bird species were identified that were particularly sensitive to loss of habitat area, simplification of habitat structure, and increase in habitat isolation. The Eastern Yellow Robin was the focal species for this catchment. It generally occurred in woodland patches larger than 10 ha that were no more than 1.5 km from other patches at least 10 ha in size, and had at least a moderate structural complexity made up of a healthy overstorey of eucalypts with an understorey of regenerating trees, shrubs, tussock grasses and fallen timber. The Saltshaker project predicted that many other woodland birds would co-occur if the habitat requirements of the Eastern Yellow Robin were met by patch and landscape scale enhancement activities.

Further works. The Saltshaker project was followed by many others since 2002. The largest project was “Boorowa River Recovery” that began in 2005 as a partnership managed by Greening Australia with the Lachlan Catchment Management Authority and the Boorowa Landcare Group.  Through a total investment of almost $2.2 million (in-kind included), this project rehabilitated or protected 640 ha of riparian area along 80 km of river including a continuous 29 km stretch of the Boorowa River above the town water supply dam (Figs 1 and 2). It involved more than 60 land managers who implemented on-ground works described in individual ten year management contracts. On-farm project size averaged 11.6 ha.

Other projects funded by a diversity of sources, particularly the Australian Government, have protected an additional 88 ha of woodland remnant, enhanced 353 ha of remnants, and revegetated 425 ha of native vegetation within the catchment.  Projects included Whole of Paddock Rehabilitation (WOPR).  All project activities linked to funding have been recorded in a detailed project management database held by Greening Australia. These additional projects were consistent with the enhancement activities recommended by the Saltshaker Project and described in the EMR feature.

Figure 2 (a) Before and (b) after willow removal in the Boorowa River Catchment. After willow removal, all sites were planted to a diversity of trees and shrubs.

Outcomes. There has been no comprehensive follow-up to the 2001 bird surveys across the Boorowa Catchment.  However since then, there is now a large and comprehensive scientific literature demonstrating dramatic increases in woodland birds in the revegetation areas in this region of southeastern NSW (reviewed in 2018). Most all the conservation and restoration activities in this catchment have likely led to an increase in woodland birds over the past 20 years.

Of all the Boorowa projects, the Boorowa River Recovery projects had sufficient funding for monitoring outcomes six years after project activities commenced. A sub-sample of 20 sites out of a pool of 47 were monitored for improvements in vegetation cover and density, macroinvertebrate abundance and stream bank stability. Planted shrub cover generally doubled at all sites as expected. Macroinvertebrate scores did not differ between treated and control sites, though activities did appear to improve stream bank stability (an indirect measure of reduced erosion).  Subsequent monitoring 12 years on showed further improvements in ecosystem function.

Since the Saltshaker Project finished, there has been no systematic monitoring of the hundreds of woodland remnants protected and enhanced by this project and subsequent ones.  However, landholders and staff anecdotally report indicative improvements in vegetation cover and wildlife habitat on the sites, and we can infer from a 2008 study that included woodland sites in the Boorowa Catchment, that significant ecological improvements are likely from fencing out livestock from woodland patches. This study found improvements included greater native floristic richness, native groundcover and overstorey regeneration within fenced sites compared to unfenced sites. Similarly, a 2009 study found that woodland sites in south eastern Australia, with livestock grazing removed, had a greater abundance of beetles and the opportunist ant functional group, a faster rate of litter decomposition, greater native plant richness, greater length of logs, and a better vegetation condition score.

Lessons learned. Long-term action with short-term funding. Natural resource management projects have been ongoing in the Boorowa catchment for over 25 years. But no single project has been funded for more than five years. This is the reality of natural resource management (NRM) in much of Australia.  Government NRM programs come and go with election cycles, but fortunately the commitment of landholders and local organisations persists.

Partnership model. All the projects before and after the Saltshaker Project have involved landholders working collaboratively with local agencies administering the diversity of funding. Most projects had a steering committee that proved a good way for stakeholders to have input through all stages of project, which was particularly important during project planning. Idealism needed to be balanced with practicality so bureaucracy was minimised while maintaining accountability. Good communication that recognised that no single view was more valuable than another was important, although full consensus was not always possible. Trust was enabled when processes were developed collectively. Skilled coordinators needed a clear understanding of their roles and care taken to not get involved in local politics.

Assessing outcomes. Developing a highly predictive understanding of ecological outcomes from NRM activities in catchments like Boorowa is a scientifically complex, expensive and long-term process. The confidence we can now claim for an increase in abundance and diversity of woodland birds in the Boorowa catchment stems from two types of monitoring. First is project monitoring of outputs like the 425 ha of revegetation known to have been established in the catchment. We know this from Greening Australia’s project management database (unfortunately there is no national database for this kind of outputs),  although satellite imagery should be able to pick up this output once plantings have a dense enough canopy. It is essential to know when and where project outputs like revegetation have occurred in order to then design scientifically rigorous studies to research ecological outcomes like increases in flora and fauna diversity and abundance. We have confidence that wildlife is colonising revegetation because research groups have conducted sophisticated statistical analyses of wildlife data from woodland revegetation in nearly 200 sites across south eastern Australia for over 15 years (summarised in a 2018 study).

Gaps in understanding. We know a lot about the ecological and social outcomes of NRM activities, but much less about improving the cost effectiveness of outputs such as revegetation and understory enhancements(see 2016 review). There are no recent published benchmarks on how much revegetation should cost in the face of variable climatic conditions, soil types and terrain.  More revegetation case studies need to be documented, but they need to include an accounting of costs.  The Australian restoration challenge is vast, funding always limited, so practical research and transparent accounting is sorely needed to reduce the cost of ecologically effective restoration.

Continuous re-learning. The many and diverse projects in the Boorowa Catchment are typical of NRM activities in Australian woodlands over the past 25 years. Each project has involved different agencies, many no longer exist or have changed their names (e.g. Catchment Management Authorities have morphed into Local Land Services in NSW). Each agency, including NGOs like Greening Australia, have a natural turn-over of staff. For example, only one staff member of Greening Australia involved in Saltshaker remains with the organisation.  Landholders tend to remain longer, but they too retire, sell out, and move on. Like education, every new staff member and every new landholder needs to learn the complex processes of successful catchment repair. This learning needs to be hands-on, hence funding for NRM activities and extension is needed in perpetuity (just like education). But experiential learning needs to be complemented with a diversity of learning resources such as the EMR journal, easily assessable reports (too many have disappeared from Government websites) and new media such as YouTube videos. Most importantly, communities of practice need to be perennially nurtured by a diversity of practitioners, experienced and less so.  There is much still to be learned and shared.

Stakeholders and Funding bodies:   The primary funding bodies for projects in the Boorowa catchment were the Australian Government, TransGrid, Alcoa Australia, the NSW Environmental Trust, and the former Lachlan Catchment Management Authority. These external funds were complemented by a diversity of in-kind support provided by farmers, Boorowa Shire Council, and other community members of the catchment.

Contact details. David Freudenberger, Fenner School of Environment and Society (Australian National University, Canberra, 0200, Australia, Email: david.freudenberger@anu.edu.au). GF, NT and AC can be contacted at Greening Australia, Kubura Pl, Aranda ACT 2614, Australia; and LG at GrassRoots Environmental, Canberra (http://www.grassrootsenviro.com/)

 

 

Restoring the banks of the Namoi on Kilmarnock – UPDATE of EMR feature

Robyn R. Watson

[Update of EMR feature – Watson R. (2009) Restoring the banks of the Namoi on ‘Kilmarnock’: Success arising from persistence. Ecological Management & Restoration,  10: 1 pp 10-19 https://onlinelibrary.wiley.com/doi/10.1111/j.1442-8903.2009.00434.x]

Figure 1. Casuarina (Casuarina cunninghamiana), River Red Gum and a range of grasses established on river bank at Kilmarnock after restoration works. (Photo R. Watson)

Riverbank restoration began on Kilmarnock in early 1990 with fencing the river area and planting native trees, shrubs and grasses. A program of killing the weeping willows resulted in their elimination by 2000. Tree lines were planted to connect the river corridor to natural conservation areas around the farm and this has resulted in a gradual increase in native wildlife leading to great environmental benefits both for the farm and surrounding areas.

Prior to the works the riparian zones on Kilmarnock had degraded to the extent that the banks were slumping during floods, with loss of old trees. This had arisen from decades of clearing, grazing and weed invasion.  Since 2009 we can report that the fenced-off river corridor has continued to recover with native grasses  beneath the trees, particularly Phragmites (Phragmites australis)  and Vetiver Grass (Chrysopogon zizaniodes) which are growing well on the steep river banks (Fig 1).  As the trees in the riparian corridor grew, additional tree lines were planted throughout the farm to connect the riparian zone to retained native vegetation areas and other set-aside conservation areas. This has led to an increase in native birds, micro bats and beneficial insect numbers.

Wildlife have returned to the area, including Little Pied Cormorant (Microcarbo melanoleucos) and  Pied Cormorant (Phalacrocorax varius) nesting in the River Red Gum (Eucalyptus camaldulensis) trees one year. Flocks of Budgerigar (Melopsittacus undulatus) and Spotted Pardalote (Pardalotus punctatus)  have been observed in the trees along the riparian zones.  Pink Eared Duck (Malacorhynchus membranaceus), Musk Duck (Biziura lobata)(, Eurasian Coot (Fulica atra) and Brolga (Antigone rubicunda) visited wetland areas on the farm. There has been a noticeable increase in the small birds such as three different wrens including Superb Fairy-wren (Malurus cyaneus) and Variegated Fairy-wren (Malurus lamberti) and Australasian Pipit (Anthus novaeseelandiae).

The planted irrigated cotton crop was not sprayed with insecticide for 12 years after the increase in beneficial insect and bird numbers. Nest boxes have been installed in the conservation areas for the micro bats.  Fourteen species of insectivorous micro bats have been recorded on the farm since the rehabilitation work began. Stubble quail (Coturnix pectoralis) have been nesting in the conservation areas.

Figure 2. Log groins with planted native trees established on steep river bend near Boggabri through the Namoi Demonstration Reach Project (2007-14) coordinated by the NSW Dept of Primary Industries. (Photo R. Watson)

Further works undertaken nearby.  After seeing the improvement on our farm some adjoining landholders have begun fencing off their river areas and introducing rehabilitation measures on their farms. In one outstanding collective example, 120 kilometres of the Namoi Demonstration Reach Project was established by the NSW Dept of Primary Industries both upstream and downstream of Kilmarnock, from 2007 to 2014.  This This involved contractors, working with permission of a number of landholders, planting over eight thousand trees and shrubs along the river and constructing log groins at a badly eroding river bend near the Boggabri township.  These groins have worked well and have withstood a couple of small floods.  The trees planted on the steep banks have also established well (Fig. 2).


Figure 3. – Planted Phragmites saved the river bank from bush fire in 2017. (Photo R. Watson)

A major bushfire in 2017 spread across the river to the top of the banks on the Kilmarnock side of the river.  Because of the planted Phragmites on the river edge there was no damage done to the toe of the river bank (Fig 3) and we were able to bulldoze firebreaks to protect  the planted trees affected from the fire.)  However, a number of the old River Red Gums were badly burnt. Many of the very old hollow trees were killed by the fire but less hollow ones have begun to grow again, although this growth has been slowed by the present drought.

With the 2019 drought conditions the Namoi River has dried out, exposing the river bed.  This has given me a chance to observe the river bed.  I have been able to photograph and document the debris on the sand banks and the remaining water holes and show that there are now substantial amounts of hollow logs and debris (Fig. 4)  which can  provide good habitat for fish and water creatures when the stream is flowing.

Our family has purchased more land downstream on the Namoi River and we have implemented rehabilitation on the river banks, tree planting and conservation measures on those farms.

Contact.  Robyn Watson, Kilmarnock, Boggabri, NSW 2382, Australia; Tel: 02 67434576 Email: wjwatson@northnet.com.au

Figure 4. Hollow log and debris on riverbed provide fish habitat when river is flowing. (Photo R. Watson)

 

Developments in Big Scrub Rainforest Restoration: UPDATE of EMR feature

Tony Parkes, Mark Dunphy, Georgina Jones and Shannon Greenfields

[Update of EMR feature article: Parkes, Tony, Mike Delaney, Mark Dunphy, Ralph Woodford, Hank Bower, Sue Bower, Darren Bailey, Rosemary Joseph, John Nagle, Tim Roberts, Stephanie Lymburner, Jen Ford and Tein McDonald (2012) Big Scrub: A cleared landscape in transition back to forest? Ecological Management & Restoration 12:3, 212-223. https://doi.org/10.1111/emr.12008]

Key words: Lowland Subtropical Rainforest, ecological restoration, seed production, landholder action, corridors

Figure 1a. Rainforest regenerators undertake camphor injection, leaving bare trees standing creating light and an opportunity for seed in the soil to naturally regenerate. (Photo © Envite Environment)

Figure 1b Aerial photo showing camphor conversion by injection
(Photo © Big Scrub Regeneration Pty. Ltd.)

Introduction. The Big Scrub, on the NSW north coast, was once the largest tract of Lowland Subtropical Rainforest (LSR) in Australia. It was reduced to less than 1% of its original extent by he end of hte 19th century after clearing for agriculture. Big Scrub Landcare (BSL) is a non-profit organisation dedicated to improving the long-term ecological functionality of what remains of this critically endangered ecosystem –  lowland subtropical rainforest.  Our 2012 EMR feature reported on remnant restoration and revegetation works overseen by BSL to 2012. At that time, 68 remnants were identified as significantly affected from the impacts of environmental degradation including weed invasion and cattle access. These remnants had been undergoing treatments, with 20 substantially recovered and on a ‘maintenance’ regime.  Approximately 900,000 trees had been planted to establish 250 ha of young diverse well-structured rainforest.  A comparatively small area of forest dominated by the highly invasive exotic, Camphor Laurel (Cinnamomum camphora) (Camphor), which  has colonised much of the Big Scrub landscape had been converted to early phase LSR by skilled removal of a range of weeds and facilitating natural regeneration. 

Progress since 2012. Substantial progress in restoring critically endangered lowland subtropical rainforest in the Big Scrub has been achieved over the past seven years in the following areas.

  • Assisted regeneration of remnants has continued and become more focused
  • Re-establishment of LSR through plantings has expanded
  • Camphor conversion has developed in scale and techniques
  • Greater security of funding has been achieved
  • Community engagement has greatly improved and expanded
  • Genome science is being applied to produce seed with optimal genetic diversity for rainforest restoration.

Assisted regeneration of remnants. This work continues to be the major focus of on-ground restoration work. About 2000 regenerator days (9 years Full Time Equivalent) of work has been undertaken in 45 remnants. BSL’s remnant restoration program has become more strategic, with more focus on Very High Conservation Value (VHCV) remnants, particularly those in the NSW National Parks Estate, including the VHCV sites in Nightcap National Park (NP) including Big Scrub Flora Reserve, Minyon Falls and Boomerang Falls; Andrew Johnston’s Scrub NR; Snow’s Gully Nature Reserve (NR); Boatharbour NR; Victoria Park NR and Davis Scrub NR, plus the Booyong Flora Reserve. Rehabilitation work at these sites is prioritised in the major new four-year Conservation Co-funding project funded jointly by BSL and the NSW government’s Saving our Species program. Big Scrub Foundation (BSF) funding has enabled BSL to continue maintenance work in remnants that have reached or are approaching the maintenance stage.

Monitoring outcomes has become more rigorous and has demonstrated ongoing improvements in vegetation structure, with decreasing levels of weed invasion and improvements in native species cover.

BSL’s partner Envite Environment, with some assistance from BSL, is creating an important linkage between Nightcap NP and Goonengerry NP by the restoration of rainforest through the progressive removal of weeds that had dominated the 80 ha Wompoo/Wanganui corridor between these two NPs.

 Re-establishment of rainforest by planting. The area of LSR is being re-established by planting on cleared land has also continued to expand.   In the last 7 years  more than 0.5 million rainforest trees have been planted in the Big Scrub region, contributing to the restoration of another 175 ha of LSR, expanding total area of re-established rainforest by another 13%. While landscape-scale landholder driven work is inevitably opportunistic rather than strategic, the establishment of new patches of LSR enhance valuable stepping-stone corridors across the Big Scrub. Since 2012 the number of regenerators working fulltime in the Big Scrub region has increased by approximately 50%.  Another trend that has strengthened in the last 7 years is that larger plantings are now being carried out by well-resourced landowners. This is accounting for about 40% of the annual plantings. Offsets for residential development account for another 40% of trees planted. The remaining 20% is made up by small landowners, cabinet timber plantations, large-scale landscaping, and other planting of Big Scrub species. This is a significant change from the more dominant grant-based small landowner/Landcare group plantings prior to 2012.

 Camphor conversion. Larger areas of Camphor forest are being converted to rainforest, with project areas increasing substantially from less than a hectare to ten and twenty hectares. BSL estimates that more than 150 ha of Camphor forest are currently under conversion. Some landowners underake camphor injection which leaves bare trees standing, creating light and an opportunity for existing native seedlings and seed in the soil (or seed dropped by perching birds) to naturally regenerate (Fig 1). Others are choosing the more expensive option of physically removing the Camphor trees and carefully leaving the rainforest regrowth (Fig 2).  Improved techniques and landholder capacity building continue to progress and camphor conversion is now a significant component of rainforest restoration.

BSL alone is facilitating the conversion of almost 40 ha of Camphor forest to LSR funded by two 3-year grants from the NSW Environmental Trust, together with contributions from the 19 landholders involved in these projects. The ecological outcomes being achieved are significant and less costly than revegetation via plantings.

Figure 2a. Camphor forest under conversion using heavy machinery leaving rainforest regrowth intact (Photo © Big Scrub Landcare)

Figure 2b. Aerial photo showing camphor conversion by removal
(Photo © Big Scrub Landcare)

Greater security of funding. Australian Government funding for biodiversity conservation is at a very low level. Competition for existing NSW state government funding is increasing. BSL therefore has continued to  develop new strategies for fund raising to ensure continuity of its long-term program for the ecological restoration of critically endangered LSR in the Big Scrub and elsewhere. Ongoing funding of at least $150,000 annually is needed to ensure the great progress made  over the past 20 years in rehabilitating remnants is  maintained and expanded to new areas of large remnants. These funds finance weed control and monitoring; weeds will always be a part of the landscape and an ongoing threat to our rainforest remnants.

Establishment of the Big Scrub Foundation in 2016 was a major development in BSL’s fund raising strategy. The Foundation received a donation of AUD $1M to establish a permanent endowment fund that is professionally invested to generate annual income that helps finance BSL’s remnant care program and its other activities. Generous donors are also enabling the Foundation to help finance the Science Saving Rainforest Program.

Figure 3a. Australian gardening celebrity Costa Gregoriou at a Big Scrub community tree planting (part of the 17th annual Big Scrub Rainforest Day) in 2015 (Photo © Big Scrub Landcare)

Figure 3b. Founder of the Australian Greens political party Bob Brown and Dr. Tony Parkes at the 18th annual Big Scrub Rainforest Day in 2016. (Photo © Big Scrub Landcare)

Community engagement. The  Big Scrub Rainforest Day continues to be BSL’s  major annual community engagement event, with the total number of attendees estimated to have exceeded 12,000 over the past 7 years; the 2016 day alone attracted more than 4000 people (Fig 3). Every second year the event is held at Rocky Creek Dam.  A new multi-event format involving many other organisations has been introduced on alternate years.

BSL’s Rainforest Restoration Manual has been updated in the recently published third edition and continues to inform and educate landowners, planners and practitioners.

BSL in partnership with Rous County Council produced a highly-commended book on the social and ecological values of the Big Scrub that has sold over 1000 copies. BSL’s website has had a major upgrade: its Facebook page is updated weekly; its e-newsletter is published every two months. BSL’s greatly improved use of social media is helping to raise its profile and contribute to generating donations from the community, local businesses and philanthropic organisations to fund its growing community education and engagement work and other activities.

Science saving rainforests program. BSL, the Royal Botanic Gardens Sydney, the BSF and their partners have commenced an internationally innovative program to apply the latest DNA sequencing and genome science to establish plantations to produce seed of key species with optimal genetic diversity for the ecological restoration of critically endangered lowland subtropical rainforest. This program will for the first time address the threat posed by fragmentation and isolation resulting from the extreme clearing of Australia’s LSR, which is estimated to have resulted in the destruction of 94% of this richly biodiverse Gondwana-descended rainforest.

Many  key  LSR species are trapped in small populations in  isolated remnants  that  lack the genetic diversity needed to adapt and survive in the long term, particularly faced with climate change Necessary  genetic diversity is also lacking in many key species in the 500 ha of planted and regrowth rainforest. The first stage of the program, already underway, involves collecting leaf samples from approximately 200 individual old growth trees in 35 remnant populations across the ranges of 19 key structural species of the ‘original’ forest. DNA will be extracted from the leaf samples of each species and sequenced. The  latest genome science will be applied to select the 20 individual trees of each species that will be cloned to provide planting stock with optimal genetic diversity for the establishment of a living seed bank in the form of a plantation that will produce seed  for use in restoration plantings. As the individual trees in the restoration plantings reproduce, seed with appropriate genetic diversity and fitness will be distributed across the landscape. The project focuses on key structural species and thus helping the survival of Australia’s critically endangered Lowland Subtropical Rainforest in the long term.

Lessons learned and current and future directions. A key lesson learned some five years ago was that BSL had grown to the point where volunteers could no longer manage the organisation effectively. BSL took a major step forward in 2015 by engaging a part-time Manager, contributing to BSL’s continuing success by expanding the scope, scale and effectiveness of its community engagement activities and improving its day to day management.

The principal lesson learned from BSL’s on-ground restoration program is to focus on rehabilitation of remnants and not to take on large planting projects, but rather support numerous partnered community tree planting events. Large grant-funded multi-site tree planting projects are too difficult to manage and to ensure landholders carry out the necessary maintenance in the medium to long term.

Acknowledgements.  BSL acknowledges our institutional Partners and receipt of funding from the NSW government’s Saving our Species program, NSW Environmental Trust and Big Scrub Foundation.

Contact:  Shannon Greenfields, Manager, Big Scrub Landcare (PO Box 106,  Bangalow NSW 2479 Australia; . Tel: +61 422 204 294; Email: info@bigscrubrainforest.org.au Web: www.bigscrubrainforest.org.au)