Category Archives: Fauna & habitat

The rise of invasive ant eradications since the success of the Kakadu project  – UPDATE of EMR feature

Posted on 3 October 2019 by | Comments Off on The rise of invasive ant eradications since the success of the Kakadu project  – UPDATE of EMR feature

Benjamin D Hoffmann

[Update of EMR feature – Hoffmann,  Benjamin D and Simon O’Connor (2004) Eradication of two exotic ants from Kakadu National Park. Ecological Management & Restoration, 5:2, 98-105. https://onlinelibrary.wiley.com/doi/10.1111/j.1442-8903.2004.00182.x]

Key words. pest species management, invasive species, biosecurity

Figure 1. Kakadu staff in 2001 spreading formicide over a super-colony of African Big-headed Ant. This involved a team of people, aligned in a row, walking from one edge of the infested area to the other in parallel paths. (Photo courtesy of Simon O’Connor.)

Introduction. Invasive species management, especially eradications, has been at the forefront of biodiversity conservation gains over the past two decades. For example, over 1,200 invasive vertebrate eradications have been achieved on over 800 islands worldwide and the conservation benefits of such actions have been overwhelmingly positive and often dramatic. Efforts against invasive ants have also been particularly notable over the past two decades, with ants now being the second-most eradicated taxa globally having been eradicated from more than 150 locations, with the largest eradication covering 8300 ha. Two decades ago there were only 12 confirmed ant eradications using modern baits with a combined area totalling a mere 12 ha.

As reported in our original EMR feature, the last treatments against two invasive ants in Kakadu National Park, northern Australia: The African Big-headed Ant (Pheidole megacephala) and the Tropical Fire Ant, (Solenopsis geminata) were conducted in 2003; and the ants were declared eradicated two years later (Hoffmann & O’Connor 2004). At the time this was a globally significant eradication, and the positive outcome was a partial catalyst for the creation of many other relatively small exotic ant eradication attempts around Australia, including against Tropical Fire Ant on Melville island, and African Big-headed Ant on Lord Howe Island. Incidentally, the work coincided with the approximate timeframe of when two other highly invasive ant species were first detected in Australia: Red Imported Fire Ant (RIFA) (Solenopsis invicta), and Electric Ant (Wasmannia auropunctata), prompting the initiation of two massive national cost-shared eradication programs. One of these, the RIFA program, has become Australia’s second-most expensive eradication program at AUD $428 million as of at July 2019. Together, all of these actions put ants high on Australia’s biosecurity and environmental management radars, prompting the development of Australia’s Tramp Ant Threat Abatement Plan and yet even more eradication programs.

Figure 2. Ant bait being dispersed aerially by helicopter using an underslung spreader and side-mounted dispersers. (Photos Ben Hoffmann)

Further advancements in ant eradication programs.  As Australia’s eradication programs became more numerous and larger, it became apparent very quickly that the methodologies and technologies available were insufficient to achieve success in the increasingly challenging conditions being encountered. In response, over the next two decades, there has been an impressive range of advancements that significantly improved our capacity to manage and eradicate invasive ant incursions.

The biggest issue was that work needed to be conducted over such large or inaccessible areas that ground-based work (Fig 1) was not feasible. So, treatments quickly became aerial, using multiple helicopter-based delivery platforms (e.g. underslung buckets and side-mounted hoppers, Fig 2). Even so, there have been locations that are too remote, too small, or too difficult (ie cliffs) to treat using a helicopter. To meet this challenge, in just the last five years treatments have been conducted for the first time using drones, and there is a great focus now to improve the technology so that it becomes more cost effective and more autonomous (Fig 3). This is occurring at such a pace that just a few years ago drones could only operate for a few hours at most on battery power, and only carry a few kilograms. This year we will be using a drone with unlimited flying capacity (petrol driven) that can lift 70 kg per load.

Figure 3. The Fazer with side-mounted bait carriers that can lift up to 40kg of payload. This is soon to be superseded by a drone that can lift a 70k g payload. (Photo Ben Hoffmann)

Assessments for the presence of ants, either before or after treatments, was originally very time consuming, involving teams of people walking ground very slowly and often utilising thousands of attractive lures (Fig 4). At most, only small ant populations (about less than 20 ha) within good working environments (ie open landscapes) could be assessed using teams of people, and it took large amounts of time. It was found very quickly that detector dogs could be trained on the scent of each ant species, and a single dog could cover more than five times the area of a team of people in a single day with greater efficacy (Fig 5). There are now more than 20 detector dogs operating in Australia and New Zealand that have been trained on the scent of four ant species. But even a team of dogs cannot fully cover entire areas at the landscape-scale, such as is the case for the RIFA program, especially in areas with long grass or rugged terrain. One of the saving technologies for the RIFA program has been the development of a multi-spectral sensor and associated algorithms that can identify RIFA nests from imagery captured by remote sensing (Fig 6). This allows program staff to assess just a few identified point locations in a landscape rather than the entirety of landscapes, to determine RIFA presence or absence. The next envisaged step is the development of biosensors that can detect the odours of target ant species, just like detector dogs, and with time these will become small enough to be transported by small drones throughout landscapes to detect ants.

Figure 4. An area covered with hundreds of flags marking spoonfulls of catfood being used as lures to attract African big-headed ant to assess eradication success or failure. (Photo Ben Hoffmann)

Figure 5. An ant detector dog searching for the presence of Red imported fire ant. (Photo courtesy of The State of Queensland (Department of Agriculture and Fisheries 2010–2019))

Australia was caught particularly unprepared two decades ago when the two new exotic ant species were detected for the first time because there were no baits registered for their management in Australia, so legally there were no treatment products that could be used. Even with the implementation of Emergency Use Permits for some unregistered products, as well as the use of the few products that were available for other species, it was often found that individual products could not be used in particular circumstances, especially around water, within crops and on organic farms. Additionally, available baits often did not have high efficacy. With time many baits (comprised of combinations of an attractive food laced with an active constituent) have been formulated and tested providing a greater array of baits that can be used on any new incursion and in numerous settings. The most recent has been the development of hydrogel baits that essentially deliver a liquid product in a solid form.

Figure 6 a and b. Multi-spectral camera flown underneath a helicopter to detect Red imported fire ant nests. (Photos courtesy of The State of Queensland (Department of Agriculture and Fisheries) 2010–2019)

Among the numerous advances described already, possibly the greatest development is on the threshold of becoming a reality, in the form of genomic solutions for individual species. RNA interference, and gene-drive technology are rapidly being developed for a suite of economically important species, and ants are among the taxa that are highest on the priority list as targets for this research. At best, these genomic advances promise to provide species-specific solutions, thereby alleviating the current non-target issues of using toxicants.

Conclusion. Our ability to eradicate ants has improved dramatically over the past two decades, with technologies and methodologies available now that were as yet not thought of back when our work was conducted in Kakadu National Park. New programs are constantly arising, and forging ahead in increasingly challenging situations, and a great deal of effort is placed in information-sharing among programs. Simultaneously there is a sustained focus to improve biosecurity at Australia’s borders, as well as throughout our region to help prevent the need for eradications in the first place.

Contact. Ben Hoffmann, Principal Research Scientist, CSIRO Health & Biosecurity (PMB 44 Winnellie NT 0822 Australia; Tel: +61 8 89448432; Email: Ben.Hoffmann@csiro.au).

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Posted in EMR 20th anniversary updates, Fauna & habitat, Indigenous land & sea management, Monitoring, Northern Territory, Pest animal issues & solutions, Pest species, Restoration & management theory, Techniques & methodology

Registration of domestic cats on Christmas Island, Indian Ocean: stage one to an eradication program for stray and feral cats to mitigate social and environmental impacts – UPDATE of EMR feature

Posted on 2 October 2019 by | Comments Off on Registration of domestic cats on Christmas Island, Indian Ocean: stage one to an eradication program for stray and feral cats to mitigate social and environmental impacts – UPDATE of EMR feature

 David Algar, Neil Hamilton and Caitlyn Pink

[Update to EMR article: Algar, David, Stefanie Hilmer, Don Nickels and Audrey Nickels (2011) Successful domestic cat neutering: first step towards eradicating cats on Christmas Island for wildlife protection. Ecological Management & Restoration, 12:2, 93-101. https://onlinelibrary.wiley.com/doi/10.1111/j.1442-8903.2011.00594.x]

Key words: domestic and feral cats, eradication program, cat de-sexing and registration, cat management, pet cat survey, local cat legislation

Figure 1. Stray cat on Christmas Island (Photo Neil Hamilton DBCA)

Introduction: In 2010 a ‘’Cat Management Plan’’ was commissioned by the various land management agencies on Christmas Island to mitigate the environmental and social impacts of cats (Felis catus) on the island (Fig 1). These impacts included contributing towards the decline of a number of native species through predation, as well as being a source of Toxoplasmosis gondii, a parasite that can lead to serious human health complications.

The plan proposed a strategy to eradicate cats entirely from the island as the domestic population died out and was adopted in late 2010. The essential first stage of the management plan was therefore the registration of all domestic cats. As part of this plan, amendments to the Local Cat Management Laws (Shire of Christmas Island Local Law for the Keeping and Control of Cats 2004 (WA)) under the Local Government Act 1995 (WA) were endorsed in August 2010. These revisions required that all domestic cats in the Shire of Christmas Island were legally bound to be de-sexed, tattooed, microchipped and registered with the Shire. The revisions were designed to limit domestic and stray/feral cat impact on the native fauna, promote responsible cat ownership, compliance and enforcement of cat management laws and prohibit the importation of new cats. Micro-chipping of domestic cats would enable the identification of those animals during trapping campaigns for stray and feral cats, so that they could be released rather than destroyed. De-sexing would prevent potential natal recruitment into the domestic, stray and feral populations. A survey of domestic cats was conducted prior to the veterinary program in October 2010 (see original feature), to guarantee that all domestic cats would be registered. One hundred and fifty-two cats were recorded during the initial survey in October 2010 of which 136 were registered as domestic pets.

Figure 2. Red-tailed Tropic-Bird with chick May 2012. (Photo Neil Hamilton DBCA)

Further works undertaken: Two further veterinary visits were conducted in May 2011 and 2012 following the domestic cat surveys to complete the veterinary program. Subsequent domestic cat surveys have been conducted each May in 2013, 2014, 2015 and 2016. In 2016 prior to the domestic cat survey, it came to our attention that a number of un-registered cats were being kept as pets. It was decided by the ‘’Christmas Island Cat Eradication Steering Committee’’ that a short-term amnesty on pet cat ownership be invoked so that these animals could also be de-sexed and registered. Following this amnesty, a final veterinary program was endorsed and fines were still issued to those residents who wanted their otherwise illegal cat to be de-sexed and registered, or unregistered cats could be handed in and euthanased without charge. Further domestic cat surveys were conducted in May 2017 and October 2018.

Further results to date: Since October 2010, 184 cats have been registered following the various veterinary programs. The survey conducted in 2018 recorded 66 registered cats remaining. The total number of domestic cats registered each year, the sex population structure, the number of new registrations and number deregistered are presented in Table 1, with the decline of two-thirds relatively steady over the years.

Table 1. Total number of domestic cats registered each year, the sex structure, the number of new registrations and number de-registered.

Date No. registered New/re-registers De-registers
  Total Female Male Total Female Male Total Female Male
October 2010 N/A N/A N/A 136 66 70 N/A N/A N/A
May 2011 138 69 69 18 10 8 16 7 9
May 2012 135 66 69 12 5 7 15 8 7
May 2013 111 53 58 0 0 0 24 13 11
May 2014 101 50 51 0 0 0 10 5 5
May 2015 87 45 42 0 0 0 14 5 9
May 2016 75 41 34 2 1 1 14 5 9
June 2016 93 49 44 18 8 10 0 0 0
May 2017 74 38 36 1 0 1 20 11 9
October 2018 66 36 30 0 0 0 8 2 6

Lessons learned and future directions: At the conclusion of the domestic cat survey in 2018, there were 66 registered cats present on the island. An additional seven domestic cats are known to have died before the planned 2019 domestic cat survey. Death of registered cats over the past nine years has been caused by a number of factors including: road fatalities; old age; disease; requests for cats to be euthanased for a variety of reasons and cats exported back to the mainland.

Domestic cats will remain on Christmas Island for a number of years, with the youngest cat approximately three years of age. Initially, as reported in the 2011 feature, it was predicted that the island would be domestic cat-free by 2024 however, this is unlikely given the subsequent and final veterinary program in 2016.

Further amendments to the island’s cat local laws were adopted in 2018, following consultation with the community and the Christmas Island Cat Eradication Steering Committee. This included an increase in penalties for illegal unregistered cats and compulsory transfer of ownership procedures to prevent future movement of registered pet cats into the designated pet cat prohibited zone. This zone protects nesting habitat for the ground-nesting Red-tailed Tropic Bird (Phaethon rubricauda, Fig 2.), where cat predation led to 90% failure of fledgling rates pre-control. Subsequent cat management in this zone has been successful in improving fledgling survival (See 2012 report).

There are several benefits of repeating the domestic cat survey each year as pet numbers decline: continue program awareness to all residents; maintain community support and involvement; offer pet health advice; thoroughly check for illegal cats to report to the Shire and respond to stray cat reports within the township. This continued effort will help ensure there is little opportunity or temptation to obtain new kittens as illegal pets while later stages of the eradication are progressing, and responsible cat ownership is maintained until the domestic cat population has died out.

The goal of eradicating cats remains highly relevant and is supported by the island community, local land management agencies and the federal government. The feasibility of long-term success is high and the outcome is likely to provide valuable lessons for other jurisdictions with social and environmental issues surrounding the presence of feral and domestic cats.

Stakeholders and Funding bodies: This is a collaborative project between Western Australian Department of Biodiversity, Conservation and Attractions and Parks Australia. The authors would like to thank Parks Australia, Christmas Island Phosphates, Shire of Christmas Island, Department of Infrastructure, Transport, Cities and Regional Development and Australian Border Force for their financial, in-kind and logistical support. Special thanks to Robert Muller, Khaleisha Amin and Chris Su for their assistance in annual surveys. The warm welcome and assistance of the whole Christmas Island community during all domestic cat surveys has been appreciated.

Contact information: David Algar, Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions (Locked Bag 104, Bentley Delivery Centre, Western Australia, Australia 6983) Email: dave.algar@dbca.wa.gov.au

 

 

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Posted in Community involvement, Cultural & socio-economic issues & solutions, Education & communication, Fauna & habitat, Island restoration, Monitoring, Pest animal issues & solutions, Threatened species & communities

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

Posted on 30 September 2019 by | Comments Off on 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

 

 

 

 

 

 

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Posted in agricultural lands, Assisted regeneration, Cultural & socio-economic issues & solutions, EMR 20th anniversary updates, Fauna & habitat, Grassland/grassy understorey, Integrating ecosystems & industries, New South Wales, Pest animal issues & solutions, Reserve management, Sclerophyll communities, Techniques & methodology, Weed issues & solutions

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

Posted on 30 September 2019 by | Comments Off on 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 words:  Paralucia 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

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Posted in Assisted regeneration, EMR 20th anniversary updates, Fauna & habitat, faunal reintroduction, Integrating ecosystems & industries, New South Wales, Restoration & management theory, Sclerophyll communities, Techniques & methodology, Threatened species & communities

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

Posted on 26 September 2019 by | Comments Off on 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/10.1046/j.1442-8903.2000.00003.x]

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

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

Posted in Assisted regeneration, Bush regeneration, climate change, Community involvement, Cultural & socio-economic issues & solutions, Ecosystem services, EMR 20th anniversary updates, Fauna & habitat, Fire Ecology & Management, History, Monitoring, New South Wales, Planning, monitoring & assessment, Reserve management, Restoration & management theory, Sclerophyll communities, Techniques & methodology, Threatened species & communities, Urban ecosystems, Weed issues & solutions

Is revegetation in the Sheep Pen Creek area, Victoria, improving Grey-crowned Babbler habitat? – UPDATE of EMR feature

Posted on 24 September 2019 by | Comments Off on Is revegetation in the Sheep Pen Creek area, Victoria, improving Grey-crowned Babbler habitat? – UPDATE of EMR feature

Doug Robinson

[Update of EMR feature  – Robinson, Doug (2006) Is revegetation in the Sheep Pen Creek area, Victoria, improving Grey‐crowned Babbler habitat?  Ecological Management & Restoration, 7:2, 93-104.  https://doi.org/10.1111/j.1442-8903.2006.00263.x]

Key words: (<5 words): Monitoring, restoration, population ecology, woodland conservation

Figure 1. Location of babbler project works and other landcare works implemented since 1996 in the Sheep Pen Creek Land Management Group area and the two sub-districts used for the babbler study. (Source TFNVic)

Introduction: The Grey-crowned Babbler (Pomatostomus temporalis) (babbler) is a threatened woodland bird (classified as Endangered in the state of Victoria) that has declined substantially in overall distribution and abundance across much of its former range in southeastern Australia since European settlement.  Sheep Pen Creek Land Management Group area, in northern Victoria (Fig 1), was fortuitously the location of the largest known remaining babbler population in Victoria in the early 1990s (when this project began); and the focus of extensive land restoration programs from the 1980s onwards to help mitigate the impacts of erosion and dryland salinity, as well as biodiversity decline.  The original study, published in 2006, investigated the overall changes in tree cover across the district between 1971 and 1996 as a result of different land-management actions and responses of local babbler populations to those habitat changes.  The key finding was that in the Koonda sub-district which had a 5% overall increase in tree cover to 14% from 1971 to 2001, showed an increase in babbler numbers by about 30% (Table 1).   In the Tamleugh sub-district, tree cover increased by 1.3% to a total of 9%, with no change in babbler numbers.  The findings also showed that new babbler groups were preferentially colonizing new patches of vegetation established that suited their habitat needs.  Building on this research, the study concluded that future conservation programs needed to scale-up the extent of habitat restoration, target areas which were suitable for babbler colonization, and tailor incentive programs to assist with conservation of particular species.

Table 1. Changes in Grey-crowned Babbler numbers over time

Year Koonda Tamleugh
number of groups number of birds number of groups number of birds
1992 20 78 11 39
1993 20 89 10 34
1996 24 96 9 35
1997 24 102 8 30
1998 25 99 10 40
2000 26 97 10 43
2005 23 99 8 34

Further revegetation works undertaken. Since the initial study’s assessment of vegetation changes between 1971 and 1996, an additional 133 ha of vegetation has been restored or established as babbler habitat in Koonda district and 37 ha in the Tamleugh district (Figs 2 and 3, Table 2).  Extensive natural regeneration, supplemented by broadscale revegetation, has also occurred over more than 350 ha on five private conservation properties in the Koonda district,, contributing to substantial landscape change.  The wider landscape has also been identified as a statewide priority for nature conservation on private land, leading to increased conservation investment in permanent protection there by Victoria’s lead covenanting body – Trust for Nature.

Monitoring of outcomes: The monitoring that was carried out prior to the 2006 publication has not continued, leaving a knowledge gap as to how the population has fared in the context of the Millenium Drought and ongoing climate-change impacts. However, based on the original research’s initial findings, we conducted an experimental study with University of Melbourne to evaluate the effectiveness of habitat restoration in maintaining babbler survival. The study, published by Vesk and colleagues in 2015, compared the persistence and group size of babbler groups present in 1995 and subsequently in 2008 at a randomly selected set of stratified sites which had either had habitat works or none.  This study was conducted across a larger landscape of about 200,000 hectares which included Sheep Pen Creek Land Management Group area.  The study found that babbler group size decreased by about 15% over the 13 years at sites without restoration works.   At sites with restoration, average group size increased by about 22%, thereby effectively compensating for the overall reduction in numbers reported over that time.This increase also influenced subsequent demographic performance, with groups at restoration sites having higher breeding success and more fledglings than groups at control sites.

Another useful finding from this experimental study was the confirmation of the importance of particular habitat and landscape variables on babbler persistence.  In particular, abundance of large trees was a positive predictor of occupancy over time; and distance from the next nearest group was a negative predictor.

Figure 2. Changes in tree cover in the Koonda sub-district between 1971 (top),  and 2018 (bottom). (Source TFNVic).. (Source TFNVic)

Figure 3. Changes in tree cover in the Tamleugh sub-district between 1971 (top) and 2018 (bottom). (Source TFNVic)

Table 2.  Summary of additional habitat established or restored as part of the Sheep Pen Creek Grey-crowned Babbler project from 1996-2018, following the initial study period from 1971-1996.

District Number of sites Area (ha)
Koonda 62 133
Tamleugh 28   37
Other parts of landcare group and local babbler population area 29 103
Totals 119 273

Expansion of lessons to other districts: Building on the fundamental research conducted in Sheep Pen Creek Land Management Group area, similar habitat, landscape and babbler population assessments were subsequently undertaken in northwest Victoria near Kerang for the babbler populations found there.  Key results from these studies relevant to the initial Sheep Pen study were that the number of babbler groups in each sampled district was positively related to the proportion of woodland cover, especially the proportion of Black Box (Eucalyptus largiflorens) woodland habitat – the babblers’ preferred habitat in this region.  Conversely, the number of babbler groups was negatively associated with the proportion of land under intensive agriculture.  At the site scale, key positive predictors of babbler presence in Black Box habitat again included the abundance of large trees (> 60 cm dbh)

Lessons learned and future directions: The most valuable lesson learned since the initial paper was published was the power of the structured research project described above to evaluate the effectiveness of the babbler conservation program and inform future design and planning. The study further demonstrated the importance of taking a demographic approach to the species’ conservation needs, understanding what is happening across the whole population over time  and how habitat interventions can assist.  These lessons have since been applied usefully to other babbler projects  and more broadly to conservation of woodland birds.

The initial paper noted the importance of achieving landscape-scale change in vegetation extent, particularly in more fertile habitats. This has occurred to some extent within the Koonda district through a range of incentive programs, tender programs, covenanting programs and land purchase, but continues to achieve most gains on more infertile land. On fertile land, by contrast, there has been rapid land-use change to cropping over the past fifteen years, leading to reduced likelihood of those properties providing suitable habitat for babblers, as found in the study conducted in northwest Victoria.

The initial paper also suggested the benefit of developing tailored incentive programs for babblers and other threatened species with particular requirements to maximize potential conservation gains  and we suggest, based on Australian and overseas experiences,  that more specific incentive programs or more detailed criteria could assist.

Another important lesson learned was the difficulty in maintaining community-driven citizen-science monitoring, even with the best will in the world, without some over-arching organizational support and oversight.  We know that community monitoring for biodiversity conservation needs scientific input at the design and analysis stages; hence additional resources may also be required in terms of equipment or guidelines to help groups monitor effectively.  Modest government investments to conservation organisations with established biodiversity monitoring programs could usefully help address this issue.

Finally, the learnings from the Sheep Pen Creek Land Management babbler conservation project over nearly thirty years are that the landscape changes and that these changes are not always positive.  Land-use change is placing more pressure on  potential babbler habitat; and the eucalypt regrowth which was established and provided new nesting resources for a few years is now too tall to provide nesting habitat, but too dense and immature to provide suitable foraging habitat for another one hundred years.  Climate change is rapidly imposing constraints on the availability of food resources and breeding opportunities, exacerbated by increased competition for the same limited resources by exotic and native species.  For the Grey-crowned Babbler, the solution to all of these factors depends on ongoing commitment to the establishment or maintenance of their essential habitat needs and life-history requirements so that their life-cycle is provisioned for from generation to generation.

Stakeholders and Funding bodies:   Most of the targeted habitat works achieved for babblers in this landscape has occurred through funding support from the Australian government through its Natural Heritage Trust and Caring for our Country programs.  Broader habitat protection and restoration has occurred primarily with funding support to landholders from the Goulburn Broken Catchment Management Authority (GBCMA).  The Norman Wettenhall Foundation, along with GBCMA, was instrumental in enabling the research by University of Melbourne, which was also aided by the extensive voluntary support of Friends of the Grey-crowned Babbler.  Not least, local landholders continued to support the project and continue to protect or restore parts of their properties to assist with babbler conservation.

Contact information: [Doug Robinson, Trust for Nature, 5/379 Collins Street Melbourne, Victoria 3000, Australia.  dougr@tfn.org.au, (03) 86315800 or 0408512441; and  School of Life Sciences, La Trobe University, Bundoora, Victoria, Australia.

 

 

 

 

Comments Off on Is revegetation in the Sheep Pen Creek area, Victoria, improving Grey-crowned Babbler habitat? – UPDATE of EMR feature

Posted in agricultural lands, Community involvement, Cultural & socio-economic issues & solutions, Ecosystem services, EMR 20th anniversary updates, Erosion issues & solutions, Fauna & habitat, Integrating ecosystems & industries, Landscape pattern & design, reconstruction, Restoration & management theory, Sclerophyll communities, Victoria

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

Posted on 19 September 2019 by | Comments Off on 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

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Posted in Assisted regeneration, Ecosystem services, Education & communication, EMR 20th anniversary updates, Fauna & habitat, Freshwater aquatic, New South Wales, Pest animal issues & solutions, Pollution issues & solutions, Sclerophyll communities, Techniques & methodology, Threatened species & communities, Urban ecosystems, Weed issues & solutions, Wetland

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

Posted on 18 September 2019 by | Comments Off on 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

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Posted in Coastal & marine, Community involvement, Ecosystem services, EMR 20th anniversary updates, Fauna & habitat, Integrating ecosystems & industries, New South Wales, Pollution issues & solutions, Urban ecosystems, Wetland

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

Posted on 17 September 2019 by | Comments Off on The biodiversity benefits of Greening Australia’s Saltshaker Project, Boorowa, NSW – UPDATE of EMR feature

David Freudenberger, Graham Fifield, Nicki Taws, Angela Calliess 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/)

 

 

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Posted in agricultural lands, Assisted regeneration, Community involvement, EMR 20th anniversary updates, Fauna & habitat, Integrating ecosystems & industries, Landscape pattern & design, New South Wales, reconstruction, Sclerophyll communities, Threatened species & communities

Ecological Restoration of Donaghys Corridor, Gadgarra, north Queensland – UPDATE of EMR feature

Posted on 17 September 2019 by | Comments Off on Ecological Restoration of Donaghys Corridor, Gadgarra, north Queensland – UPDATE of EMR feature

Nigel Tucker

[Update of EMR feature – Tucker, Nigel I. J. and Tania Simmons (209) Restoring a rainforest habitat linkage in north Queensland: Donaghy’s Corridor, Ecological Management & Restoration, 10:2, 98-112, https://onlinelibrary.wiley.com/doi/10.1111/j.1442-8903.2009.00471.x]

Keywords: Rainforest, corridor, regeneration, disturbance effects

Introduction. Complex notophyll vine forests of the Atherton Tablelands, particularly from basalt derived soils, have been significantly fragmented and degraded by human settlement over a 100yr period. Fragment isolation results in edge effects, exotic species colonisation, loss of genetic variability and species decline. During high rainfall events, eroding streambanks on farms mobilise sediments to the receiving environment of the Great Barrier Reef. Re-connecting isolated fragments to larger forest blocks through restored riparian corridors aims to reverse these effects through adaptive management. The restoration of Donaghys Corridor is an example of adaptive management, and its establishment was a key factor in the adoption of other local corridor projects.

As reported in the 2009 features, around 20,000 plants of selected local species were established in four yearly plantings (1995/96/97/98) along Toohey Creek, creating a continuous habitat corridor between the isolated Lake Barrine fragment (500ha) and the adjacent Gadgarra section of Wooroonooran N.P (80,000ha), both being part of the Wet Tropics World Heritage Area. The corridor is 1,200m in length and 100m wide, with three rows of Hoop Pine (Araucaria cunninghamiana) planted either side of the fenced corridor, which was established on lands largely owned by the Donaghy family. On completion, the corridor was secured through the Queensland Government’s declaration of Donaghys Corridor Nature Refuge, the State’s first Nature Refuge proclaimed over an ecologically restored site.

Ongoing recovery. In 2000, a vegetation survey of 3m x 5m plots in 12 permanent transects throughout the corridor showed regeneration had occurred upon canopy closure (Tucker and Simmons 2009).  Between 1995 and 1998, 119 native species had regenerated within the transects, mainly through vertebrate-mediated dispersal. The most recent (ongoing) survey, ca.20yrs after planting, indicates that regeneration has continued, and the majority of regenerating species are again vertebrate dispersed. There has also been a measurable increase in vegetation structural complexity, and a variety of life forms are present including ferns, orchids, vines, scramblers and canopy trees.

Restored vegetation in 2000 was characterised by vegetation of even age and size classes and only a developing canopy was present (no sub-canopy). Recruitment was limited to the ground storey. Over 20yrs, total numbers of recruiting species have increased, along with canopy height, and the sub-canopy is now a distinguishable and measurable feature. To illustrate this change, species diversity and structure in two typical transects from the oldest (1995) and youngest (1998) plantings are shown in the table below. Figures are from the most recent survey (2019) and the bracketed numbers indicate comparative values in 2000.

Canopy

height

 Sub-canopy

Height

 Number of species Average number of species/plot Average number of species/plot – sub-canopy Average number of species/plot – ground storey
1995 19.9 (5) 7.5 (0) 84 (53) 22.6 (12.5) 8.3 13.8
1998 14.4 (2.5) 7.3 (0) 63 (15) 14.2 (1.6) 2.2 15.8

There has also been a significant difference in the distribution of regenerating vegetation. In 2000, regeneration was negatively correlated with edge, being concentrated in the central portion of each transect. Greater structural complexity and increased shading have significantly reduced the edge effect and regeneration is now distributed equally across the entire width of the corridor. This edge-effect reduction may partially result from the three Hoop Pine rows, now ca.15m tall, planted on each side of the corridor.

Figure 1.  Part of the 18m x 250m fence crossing Donaghys Corridor

Natural and man-made disturbance. Since establishment there has been both natural and anthropogenic disturbance. Occasional incursions by cattle have occurred, entering via fences sometimes damaged by branches falling from maturing corridor vegetation. In small areas incursions have visibly damaged regeneration but surveys show this has not significantly affected regeneration. Feral pig disturbance has also occurred but does not appear to have affected regeneration.

In 2006, corridor vegetation was damaged by severe tropical Cyclone Larry. Most stems lost crowns and some waters’ edge stems were permanently bent by floodwaters, but vegetation recovery was rapid and no weed invasion occurred. This infers a measure of resilience by restored vegetation to disturbance, and the distribution of regeneration described above supports this inference.

Anthropogenic disturbance has been more interventionist and not aligned to the original concept adopted by government, landholders, scientists and the community when the project commenced in 1995.  In 2017, the corridor’s upstream neighbour, with support from the DES but without consultation with the Donaghy family or other affected landholders, erected a chain mesh fence 250m long and 1.8m high across the western end of the corridor (see Figure 1). This is part of a larger fence which completely encloses mature forest at the western end of the corridor, including corrugated iron placed across the bed of Toohey Creek. Enquiries revealed the fence is part of an enclosure for a Cassowary (Casuarius casuarius johnsonii) rehabilitation facility, operated by Rainforest Reserves Australia (RRA) under a commercial arrangement with the Queensland Government.

Enhancing landscape permeability was the key reason for undertaking the Donaghys Corridor project, and the endangered Cassowary was a key target species; 53 Cassowary food plants were included in the original planting matrix of 100 species to encourage corridor utilisation. The Queensland Government notes that corridors are a key strategy in Cassowary conservation. In addition to blocking the movement of terrestrial vertebrates such as Cassowaries, Pademelon (Thylogale stigmatica) and Musky Rat Kangaroo (Hypsiprymnodon moschatus), construction of the enclosure has inadvertently fenced in a number of animals whose territories included part of the enclosure.

DES has advised that the fence is temporary and will be removed when restoration plantings on RRA lands are ‘sufficiently well-developed’ to support Cassowaries being rehabilitated.  It is unknown, however, when or through what processes this removal will occur. Resolution of the issue is anticipated.  However, such actions highlight the pitfalls associated with single-species conservation, and potential conflicts that might arise when responsibility for management of endangered species moves from the State to the non-scientific, commercially-focused private sector. Whilst iconic wildlife e.g., the Cassowary, can be effective in harnessing community and landholder participation in restoration, here it is clear that decision making and communication has been far from optimal, which may well lead to landholder and community disillusionment. In this case, the fence has also disrupted ongoing monitoring and evaluation. Planned re-survey of terrestrial vertebrate colonisation and movement has now been cancelled, given the unknown effect of the fence on wildlife passage and the behaviour of animals inadvertently trapped within the enclosure.

Lessons learned.  The project shows that sustained regeneration of native species can be achieved in restored tropical vegetation, along with increased structural complexity and functional resilience to natural disturbance.  However, the fencing incident shows that dysfunction in a restoration project can arise from totally unanticipated causes, potentially undoing well-established partnerships between government, community, scientists and landholders.

Contact.  Nigel Tucker, Director & Principal Environmental Scientist, Biotropica.  PO Box 866 Malanda QLD 4885 ; Email: nigeltucker@biotropica.com.au; Tel: +61 7 4095 1116.

 

 

 

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Posted in agricultural lands, Assisted regeneration, Community involvement, Ecosystem services, EMR 20th anniversary updates, Fauna & habitat, Integrating ecosystems & industries, Landscape pattern & design, Queensland, Rainforest, reconstruction