Category Archives: Monitoring

The ecological restoration of Te Motu Tapu a Taikehu, Hauraki Gulf, New Zealand

The Motutapu Restoration Trust 

Introduction. Te Motu Tapu a Taikehu (Motutapu Island, 1509 ha) is located in the Hauraki Gulf Marine Park, situated on the east coast of the north of New  Zealand’s North Island. It lies immediately adjacent to Rangitoto Island which is a volcano that last erupted approximately 500-550 years ago. This, and previous eruptions would have regularly devastated the forest and wetland ecosystems on Motutapu.

After a history of Maori settlement, European clearing and farming and use for military purposes during WWII, the Island was transferred to what is now the Department of Conservation (DOC) in 1970. The island is now designated a recreation reserve, open to the public.

Pollen records suggest that after the Rangitoto eruptions ceased around AD 1500, Motutapu recovered to be covered by a patchwork of lowland podocarp/broadleaf forest typical of that found in the Auckland region, and presumably was habitat to birds, reptiles, bats, fish and invertebrates similar to those on other Northland islands and the mainland.

Habitat loss through anthropogenic disturbances including fire, clearing for farming, and the introduction of mammalian predators saw many species of native bird, reptile and plants extirpated. Prior to restoration started in 1994, Motutapu was almost entirely covered by pastoral grassland dominated by exotic species, except for a few, very small forest remnants, and a depauperate native faunal communities.

Motutapu Island is a 40-minute ferry journey from Auckland City. Map: Department of Conservation

Restoration project

Planning of the ecological restoration program is undertaken by the Natural Heritage Committee of the Trust, a group of some 15 volunteers who meet monthly to plan, and discuss implementation. Members are highly qualified, skilled and enthusiastic practitioners. Together the committee  brings sound ecological theory and practice to the  restoration of flora and fauna. Published plans they work from include the 1994 Motutapu Restoration Working Plan and subsequent 2010 audit.

The objective is to return the island forest and wetland ecosystems to a post-eruption state, with a goal of reaching 500 ha of restored forest and wetland over coming decades. Although this area is far less than the full area of the island, it allows the conservation of cultural and archaeological sites, such as pā, WWII infrastructure, and farming landscapes. The post-eruption state can be described as lowland mixed broadleaf/podocarp forest, with a suite of seabirds, waders, forest birds, reptiles, bats and invertebrates interacting with each other so that natural evolutionary processes can once more resume for these taxa on the island.

Implementation of the ecological restoration of Motutapu has been underway for 23 years, since the formation of the Motutapu Restoration Trust (MRT) in 1994. To date,  in excess of 100 ha of pasture has been converted  to pioneer forest representing an estimated 450,000+ trees  planted. Volunteer hours total 21,462 between  2005 and 2015, and is currently in excess of 3,200 hours annually.

The major activities of the ecological restoration are:

  • Seed collecting from the island and wider Auckland region
  • Plant propagation in the island nursery – year round
  • Planting in the winter months
  • Weeding year round
  • Fauna translocation and monitoring (birds, reptiles, fish and crustacea) in conjunction with DOC

Planters in action: Photo: MRT

15,136 plants went into Hospital B paddock; one of the most difficult planting sites on the island.
Photo: MRT

Home Bay forest, with Motuihe Island and the Auckland mainland in the background. Photo: MRT

Revegetation. The original strategy (1994 – 2009) was to initiate successional processes by planting pioneer phase species, which would later give way to mature phase species dispersed naturally by birds. However, it was realized that mature phase species would be slow to arrive, as the island is isolated from native forests on nearby islands and seed dispersal from them is unlikely. If seed is dispersed from its own remnant forests, any new forest will continue to reflect the depauperate nature of these remnants.

In 2010, the planting strategy was updated to include enrichment planting of mature phase forest species into the forests planted up to 15 years earlier. Seeds for this were eco-sourced from the wider Auckland region, within boundaries agreed with DOC, and brought to the island nursery for propagation. This was an opportunity to return species to the island that are currently absent, including Swamp Maire (Syzygium maire), Tree  Fuchsia (Fuchsia excorticata),  Pigeonwood (Hedycarya  arborea), White Maire (Nestegis lanceolata), Black Maire (N. cunninghamii), Turepo (Streblus  banksii) and a number  of podocarps including Matai (Prumnopitys taxifolia), Miro (P. ferruginea) and Rimu (Dacrydium cupressinum).

The project has a large nursery, operated by one full time volunteer and supported by other volunteers during the week and weekends. The nursery provides all the plants for the planting programme. Seed is collected by a small team of collectors who travel Auckland’s and the Island’s forest remnants for seeds all year round. Growing media is supplied pro bono by Daltons and Living Earth and delivered by DOC boat. The risk of importing the introduced pests Rainbow Skink (Lampropholis delicata) as eggs and Argentine Ant (Linepithema humile) precludes bringing potted plants onto the island.

Weeds such as Woolly Nightshade (Solanum mauritianum),  Moth  Vine (Araujia  sericifera), Evergreen  Buckthorn (Rhamnus alaternus), Apple of Sodom (Solanum linnaeanum), pampas (Cortaderia  spp.), and Boneseed (Chrysanthemoides monilifera) have been  present on the  island for many years, and in pasture had been kept in check by grazing. However, when pasture is retired, populations of these weeds  explode and threaten the plantings on not only Motutapu  Island, but also by dispersal to neighbouring Hauraki Gulf Islands. In particular, Rangitoto Island is threatened by invasion of weeds from Motutapu.

Weeding of the planted forests takes place in a strategic and planned way year round. Volunteers routinely grid search the plantations and control the infestations (using the hip chain method). Sources of reinfestation on other parts of the island are addressed by contractors who have the training to get at inaccessible weeds (e.g., cliff faces). New drone technology is in the process of being recruited to  identify infestations of weeds  from the  air, where they cannot be seen from the ground, or where access is particularly hazardous (e.g., cliff faces).

Pest species management. The suite of mammalian predators and herbivores on the Island prior to 2009 were detrimental to both flora and fauna, and their continued presence would have meant that neither locally extinct bird and plant species could be reintroduced, nor palatable plant species thrive.  These pests included: rats (Rattus rattus,  R. norvegicus, R. exulans); House Mouse (Mus musculus); Stoat (Mustela erminea); feral Cat (Felis catus); Hedgehog  (Erinaceus  europaeus occidentalis) and the European Rabbit (Oryctolagus cuniculus).

The successful eradication of pests from Motutapu and Rangitoto Islands was undertaken by DOC in 2009 using helicopters to disperse broadifacoum. DOC employs a biosecurity ranger on the island who responds to any new rat, stoat or other incursions.

Recent arrivals of North Island brown kiwi bring the total to 26, closer to the target of 40 required for a founder population. Photo: MRT

Further releases of takahē will bring the breeding
pairs to a total of 20, the largest total outside Fiordland. Photo: MRT

Faunal translocations. A major milestone was the declaration in 2011 of pest-free status for the Island, and the subsequent re-introductions of birds and aquatic taxa that this allowed.

The island’s pest-free status gives safe refuge to some of New Zealand’s rarest bird species. Since it became pest-free, the following rare, endangered and non-threatened species have been translocated:

  • Coromandel Brown Kiwi (Apteryx mantelli)
  • Takahē (Porphyrio hochstetteri)
  • Tīeke (Philesturnus rufusater)
  • Shore Plover (Thinornis  novaeseelandiae)
  • Whitehead (Mohoua albicilla)
  • Pāteke (Anas chlorotis)
  • Redfin bully (Gobiomorphus huttoni)
  • Koura (Paranephrops planifrons)

Survey and Monitoring.  Annual surveys of terrestrial birds and shorebirds by the Ornithological Society of New Zealand have been undertaken since 2007. As well,  a survey of seabirds nesting on the island is underway, and monitoring of translocated birds by MRT volunteers in association with DOC is ongoing. Stream fauna and reptiles are surveyed and reported on annually by DOC.

The Island’s native and exotic plants are also being surveyed to ascertain progress of the recovery over time, and plant survival rates have been monitored informally via regular tours of the plantings to assess what is working and what is not.

Evidence that recovery processes are securely occurring on the island

It is clear that the 100ha of restored vegetation has resulted in natural processes of vegetation recovery occurring, with natural regeneration evident for many species. Once the fruiting forest is fully established on Motutapu Island we envisage that it will be fully self-sustaining via seed dispersal by frugivorous birds.

Populations of fauna, with four exceptions, appear to be self-sustainable on Island. Many of the reintroduced bird species are clearly reproducing on the island and populations are growing without human intervention as evidenced by our bird surveys. The exceptions are Shore plover and Pāteke which naturally disperse away from the Island, necessitating several translocations to ensure the populations build to create a resident population, and are viable. Kiwi and Takahē populations are still being built up to founder population size.

 Bird species (terrestrial diurnal including waders):

  • an increase from 50 species in 2010 to 60 in 2015
  • Re-introduced populations expanding: Takahē, Whitehead,  Tīeke
  • Self-introduced or now detectable: Kākāriki (Cyanoramphus novaezelandiae), Bellbird (Anthornis melanura), Spotless Crake (Porzana tabuensis), Little Blue Penguin (Eudyptula minor), Banded Rail (Gallirallus phillipensis), Grey-faced Storm Petrel (Pterodroma macroptera  gouldi).

Reptiles: Population and range expansions of the four native and one introduced species. The following are the natives:

  • Common Gecko (Woodworthia maculatus): up to ten-fold at some sites since 2008
  • Suter’s Skink (Oligosoma suteri): up to a hundred-fold at some sites since 2008 baseline
  • Copper Skink (Cyclodina aeneum): up to ten-fold at some sites since 2008 baseline
  • Moko Skink (Oligosoma moco): up to ten-fold at some sites since 2008

Fish:

  • Giant kokopu (Galaxius argenteus) now

Secure engagement with local  stakeholders.

There are a number of stakeholders that are fully engaged in the project through the MRT,  including:

  • Department of Conservation – MRT’s partner since the inception of the Trust in 1994, which has been responsible for some of our biggest milestones, such as the eradication of mammalian predators 2009-2011.
  • Motutapu Farms Ltd – leases the pasture from DOC to farm beef and sheep, becoming Auckland’s largest Another long-standing partner, helping the ecology of the island and wider Hauraki Gulf by farming organically.
  • Ngāi Tai ki Tamaki – the iwi who have mana whenua on the island and give their blessing to reintroduced fauna
  • Ngāti Paoa & Ngāti Tamaterā – Coromandel iwi who are kaitiaki of the North Island Brown Kiwi (Coromandel  subspecies) on
  • Motutapu Outdoor Education Centre (MOEC)  – use the island for accommodation of school groups gaining outdoor
  • Pāteke recovery
  • Takahē recovery group
  • Auckland Zoo – monitoring the populations of Redfin Bully ( Gobiomorphus huttoni) and Koura (Paranephrops planifrons).

Contact : Liz Brooks, Manager, Motutapu Restoration Trust, Newmarket, Auckland 1149, New Zealand.  Tel: +64 9 455 9634; PO Box 99 827; Email:  liz@motutapu.org.nz

 

A framework and toolbox for assessing and monitoring swamp condition and ecosystem health

Key words: Upland swamp, stygofauna, sedimentology, ecosystem processes, biological indicators, geomorphology

Introduction. Upland swamps are under increasing pressure from anthropogenic activities, including catchment urbanization, longwall mining, and recreational activities, all under the omnipresent influence of global climate change. The effective management of upland swamps, and the prioritisation of swamps for conservation and restoration requires a robust means of assessing ecosystem health. In this project we are developing a range of ecological and geomorphic indicators and benchmarks of condition specifically for THPSS. Based on a multi-metric approach to ecosystem health assessment, these multiple indicators and benchmarks will be integrated into an ultimate index that reflects the health of the swamp.

In this project we have adopted (and modified) the definition of ecosystem health applied to groundwater ecosystems by Korbel & Hose (2011). We define ecosystem health of a swamp as, i.e., “an expression of a swamp’s ability to sustain its ecological functioning (vigour and resilience) in accordance with its organisation while maintaining the provision of ecosystem goods and services”.

Design. Our approach to develop indicators of swamp health followed those used to develop multimetric indices of river and groundwater ecosystem health (e.g. Korbel & Hose 2011). We used the ‘reference condition’ approach in which a number of un- or minimally disturbed swamps were sampled and the variation in the metric or index then represents the range of acceptable conditions (Bailey et al. 1998; Brierley & Fryirs 2005).

We focused initially on swamps in the Blue Mountains area. Reference (nominally unimpacted) and test sites with various degrees and types of impacts were identified using the database developed by the concurrent THPSS mapping project (Fryirs and Hose, this volume).

Following our definition of ecosystem health, we selected a broad suite of indicators that reflect the ecosystem structure (biotic composition and geomorphic structure) and function, including those relating to ecosystem services such as microbially-mediated biogeochemical functions, geomorphic processes and hydrological function, as well as the presence of stressors, such as catchment changes. Piezometers and dataloggers have been installed in a number of swamps to provide continuous data on groundwater level fluctuations and sediment cores taken at the time of piezometer installation have provided detailed information on the sedimentary structure, function and condition of the swamps.

Results. Intact and channelised swamps represent two geomorphic condition states for THPSS. Not surprisingly, variables reflecting the degree of catchment disturbance (such as urbanization) were strongly correlated with degraded swamp condition. Variables related to the intrinsic properties of swamps had little relationship to their geomorphic condition (Fryirs et al. 2016). Intact and channelized swamps present with typically different sediment structures. There were significant differences in the texture and thickness of sedimentary layers, C: N ratios and gravimetric moisture content between intact swamps and channelised swamps (Friedman & Fryirs 2015). The presence and thickness of a layer of contemporary sand in almost all channelised swamps and its absence in almost all intact swamps is a distinctive structural difference.

Disturbed swamps have poorer water quality at their downstream end, and associated with this, lower rates of organic matter processing occurring within the streams (Hardwick unpublished PhD Data). Similarly, the richness and abundance of aquatic invertebrates living within swamp sediments (stygofauna) is poorer in heavily disturbed swamps than in undisturbed or minimally disturbed areas (Hose unpublished data).

Within the swamp sediments, important biogeochemical processes, such as denitrification and methanogenesis, are undertaken by bacteria. In this study we are measuring the abundance of the functional genes such as a surrogate for functional activity within the swamp sediments. There is large spatial variation in the abundance of functional genes even within a swamp, which complicates comparisons between swamps. Within our focus swamp, the location closest to large stormwater outlets had different functional gene abundances, in particular more methanogens, than in less disturbed areas of the swamp. There were greater abundances of denitrification genes, nirS and nosZ, in shallower depths despite denitrification being an anoxic process, which may reflect changes in the surficial sediments due to disturbance. Overall however, the abundance of functional genes seem to vary more with depth than with location, which means that comparisons between swamps must ensure consistency of depth when sampling sediments (Christiansen, unpublished PhD data).

The list of indicators currently being tested in this project and by others in this program (Table 1) will be refined and incorporated into the final assessment framework. Thresholds for these indicators will be determined based on the range of conditions observed at the reference sites. The overall site health metric will reflect the proportion of indicators which pass with respect to the defined threshold criteria. At this stage, the final metrics will be treated equally, but appropriate weightings of specific metrics within the final assessment will be explored through further stakeholder consultation.

Stakeholders and Funding bodies. This research has been undertaken as PhD research projects of Kirsten Cowley, Lorraine Hardwick and Nicole Christiansen at Macquarie University. The research was funded through the Temperate Highland Peat Swamps on Sandstone Research Program (THPSS Research Program). This Program was funded through an enforceable undertaking as per section 486A of the Environment Protection and Biodiversity Conservation Act 1999 between the Minister for the Environment, Springvale Coal Pty Ltd and Centennial Angus Place Pty Ltd.  Further information on the enforceable undertaking and the terms of the THPSS Research Program can be found at www.environment.gov.au/news/2011/10/21/centennial-coal-fund-145-million-research-program. This project was also partly funded by an ARC Linkage Grant (LP130100120) and a Macquarie University Research and Development Grant (MQRDG) awarded to A/Prof. Kirstie Fryirs and A/Prof. Grant Hose at Macquarie University. We also thank David Keith, Alan Lane, Michael Hensen, Marcus Schnell, Trevor Delves and Tim Green.

Contact information. A/Prof. Grant Hose, Department of Biological Sciences, Macquarie University (North Ryde, NSW 2109; +61298508367; grant.hose@mq.edu.au); and A/Prof. Kirstie Fryirs, Department of Environmental Sciences, Macquarie University (North Ryde, NSW 2109; +61298508367; kirstie.fryirs@mq.edu.au).

Table 1. List of indicators of swamp condition that are being trialled for inclusion in the swamp health assesment toolbox.

Functional indicators table

Landscape-scale terrestrial revegetation around the Coorong, Lower Lakes and Murray Mouth, South Australia

Hafiz Stewart, Ross Meffin, Sacha Jellinek

Key words. Restoration, prioritisation, woodland, ecosystems

Introduction. Located in South Australia at the terminus of the Murray-Darling River, the Coorong, Lower Lakes and Murray Mouth (CLLMM) region has immense ecological, economic and cultural importance. The landscape varies from the low hills of Mount Lofty Ranges in the northwest, through the low valleys and plains surrounding Lake Alexandrina and Lake Albert, to the plains and dunes of the Coorong in the southeast (Fig 1). These landforms had a large influence on the composition of pre-European vegetation communities in the region, with the Mount Lofty Ranges dominated by eucalypt forests and woodlands, the lakes surrounded by a mixture of mallee, temperate shrublands and wetland vegetation, and the Coorong supporting coastal and wetland vegetation communities.

The region has been extensively cleared since European settlement and the introduction of intensive agriculture (cropping and grazing), so that now only a fraction of the original native vegetation remains. This has resulted in a substantial decline in biodiversity and recognition of the area as a critically endangered eco-region. These impacts have been compounded by water extraction upstream and anthropogenic changes to hydrological regimes. The recent drought further exacerbated these environmental problems and severely affected the region’s people and economy.

Fig. 1. The Coorong, Lower Lakes and Murray Mouth region showing terrestrial and aquatic plantings.

Figure 1. The Coorong, Lower Lakes and Murray Mouth region showing terrestrial and aquatic plantings.

Broad aim and any specific objectives. In response to drought and other issues affecting the region the Australian and South Australian governments funded the landscape-scale CLLMM Recovery Project (2011 – 2016). This project aims to help restore the ecological character of the site and build resilience in the region’s ecosystems and communities. As a part of this, the CLLMM Vegetation Program aimed to strategically restore native vegetation to buffer and increase the connectivity of existing remnants.

Works undertaken. Three key tools were utilised to achieve these goals. First, an integrated Landscape Assessment was used to identify priority plant communities for restoration in the region. To do this, we classified vegetation types occurring in the CLLMM landscape, then identified suites of bird species associated with each vegetation type. The status and trends of each of these bird species were then used as indicators to determine the conservation priority of each vegetation type. Second, a framework was developed to identify the most appropriate vegetation types to reconstruct at a given site, depending on characteristics such as soil type and landform. This was based on the composition and structure of remnant communities and their associated environmental settings. Finally, a Marxan analysis was conducted across the region to prioritise sites for restoration works based on the aims of the program, with an aspirational target of restoring 30% of each priority vegetation type. Following an expression of interest process that made use of existing networks in the local community and the traditional owners of the CLLMM and surrounding area, the Ngarrindjeri, prioritised sites were then selected from those made available by landholders.

For each site, we developed a plan specifying the site preparation required, and species and densities to be planted. Native plants were sourced from local nurseries, ensuring that provenance and appropriate collection guidelines were followed. Tubestock was used to provide an opportunity for social benefits, including the development of community run nurseries, and due to their higher survival rates. Planting was carried out by regional contractors engaged by the CLLMM Recovery Project Vegetation Program, along with the Goolwa to Wellington Local Action Planning association and the Ngarrindjeri Regional Authority. During this program wetland restoration was also undertaken through the planting of a native sedge species, the River Club Rush (Schoenoplectus tabernaemontani), which assisted in stabilising shorelines and creating habitat for aquatic plant communities.

Results to date. By the end of the program around 5 million native plants will have been planted at 148 sites on private and public land covering more than 1,700 hectares (Fig. 1). In total 202 species of plants have currently been planted, comprising 11% overstorey, 38% midstorey and 51% understorey species. Initial results indicate that around 66% of plants survive the first summer, at which point they are well established. Woodland and mallee bird species are starting to use these revegetated areas. When compared to remnant areas of the same vegetation type, both native plant species richness and bird diversity are lower in restored habitats. However, while the bird communities in restored habitats are dominated by generalist species, specialist species such as endangered Mount Lofty Ranges Southern Emu-Wrens have been recorded in revegetated areas, providing early signs that planted areas are benefiting rarer species. The restored communities are still very young, and over time we expect these areas will start to structurally resemble remnant habitats.

Lessons learned and future directions. Resourcing of research alongside program delivery allowed us to implement a sound prioritisation process and a systematic, strategic, and effective approach to the restoration of the landscape. The capacity to collect good vegetation, soil and bird occurrence data was crucial to this. Successful delivery also required funding for site preparation and follow-up, a well-developed network of native plant nurseries, engaged community and indigenous groups, and good relationships with local landholders.

Stakeholders and Funding bodies. The CLLMM Vegetation Program is a landscape scale habitat restoration project, jointly funded by the Australian and South Australian governments under the Coorong, Lower Lakes and Murray Mouth Recovery Project. We would like to thank the Goolwa to Wellington Local Action Planning Association, the Milang and Districts Community Association and the Ngarrindjeri Regional Authority for their assistance in undertaking this revegetation. DEWNR’s Science, Monitoring and Knowledge branch undertook the initial ecosystem analysis.

Contact information.  Hafiz Stewart, Department of Environment, Water and Natural Resources, South Australia. Hafiz.stewart@sa.gov.au

Peniup Ecological Restoration Project

Justin Jonson

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Figure 5. Map showing distribution of Proteaceous Nodes.

Figure 5. Distribution of Proteaceous Nodes.

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

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

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

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

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

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

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

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

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

See also EMR summary Monjebup

See also EMR feature article Penium project

Watch video: Justin Jonson 2014 AABR presentation on Peniup

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

Fig 9. Peniup recovery wheel template

Evaluation table2

Penrhyn Estuary Habitat Enhancement Plan: Habitat Rehabilitation for Migratory Shorebirds in Botany Bay, NSW

Peggy O’Donnell

Keywords: estuarine, restoration, saltmarsh, seagrass, roosting habitat, feeding habitat

Introduction: The Penrhyn Estuary Habitat Enhancement Plan (PEHEP) is an ambitious rehabilitation project undertaken to compensate for habitat loss due to the expansion of Port Botany. Development in Botany Bay, NSW, has caused substantial biophysical changes since the 1940s. Shorebird habitat has decreased due to airport development and expansion and Foreshore Beach is greatly reduced. Penrhyn Estuary is the only remaining significant shorebird roosting and feeding habitat along the northern shoreline but has legacy pollution. The PEHEP was prepared as part of development approval and implemented from 2012 to 2017.

Figure 1: Penrhyn Estuary 2008, before port expansion.

Figure 1: Penrhyn Estuary 2008, before port expansion.

Figure 2: Penrhyn Estuary 2015, four years after port expansion works.

Figure 2: Penrhyn Estuary 2015, four years after port expansion works.

Broad aims and works: The PEHEP aims to rehabilitate the estuary by expanding roosting and feeding grounds for migratory shorebirds and thereby increase their populations in line with Australia’s international responsibilities for shorebird conservation. Key works included levelling of sand dunes to create saltmarsh habitat and expansion of existing intertidal sand flats by filling deeper parts of the estuary with dune sand. A flushing channel was constructed to ensure adequate tidal exchange and to provide habitat suitable for seagrass beds. Protected seagrass, Strapweed (Posidonia australis) was transplanted prior to works and remaining Eelgrass (Zostera capricorni) and Paddleweed (Halophila ovalis) were protected from damage during construction using silt curtains. Local saltmarsh species planted were optimal for use as roosting habitat and extensive weed removal and maintenance was undertaken. Sound barriers, lighting and fencing around the estuary and port structure were designed to favour shorebirds and deter predators.

Monitoring programs compared baseline and post-rehabilitation conditions to assess rehabilitation efficacy. Surveys were done within the estuary and at appropriate reference locations within a BACI experimental design framework. Indicators included: abundance of key shorebird species, benthic infaunal communities, planted and transplanted saltmarsh, remnant and transplanted seagrasses off Foreshore Beach, and water quality.

Results to date:

Water Quality. Four years after habitat enhancement, physiochemical properties (temperature, pH, dissolved oxygen, salinity, total suspended solids, key nutrients) and a productivity indicator (chlorophyll a) were not significantly different from pre-construction or reference values. The configuration of the flushing channel simulated modelled estuary flushing times No algal blooms have been identified to date, suggesting the absence of eutrophic conditions within the now shallower estuary.

Saltmarsh habitat. After planting propagules the total area of saltmarsh habitat in Penrhyn Estuary exceeds 40,000 m2, a 76% increase post port construction and habitat creation (see Sainty 2016 and Dalby-Ball & Olsen 2016 for details of saltmarsh design and planting methodology). Following the works, saltmarsh species diversity, abundance and condition all improved.

The newly-planted saltmarsh vegetation appeared healthy showing continued growth with variability mainly at the margins of planted beds. The main roosting habitat species Salt Couch (Sporobolus virginicus) increased in all treatments, while Seablight (Suaeda australis) decreased slightly consistent with its removal in strategic locations to maintain plant height favourable for shorebird roosting habitat. The ecological function of planted saltmarsh areas was similar to that at reference locations (including other constructed saltmarsh habitats) and a trend of increasing biodiversity was observed throughout the three post-rehabilitation surveys. Some habitats treatments have not responded as well, including those transplanted prior to enhancement works and areas that were cleared of mangroves and weeds. Overall, the majority of ecological targets set with respect to the saltmarsh vegetation within Penrhyn Estuary were met.

Benthic intertidal habitat. Unvegetated intertidal feeding habitat for migratory shorebirds increased by 307% as a result of filling deeper parts of the estuary with dune sand. To enhance invertebrate abundance and diversity, dune sand was augmented with seagrass wrack and river mud as it was profiled in the estuary. Earthworks were staged such that tidal exchange with Botany Bay was altered and/or restricted but never eliminated during the two year construction period.

Criteria for the success of habitat creation were derived from comparison to target values based on pre-enhancement surveys and reference locations. Physical indicators were median grain size and percentage of fine sediments (% clay and silt fractions). Biological indicators were invertebrate abundance and biomass.

After habitat enhancement targets for invertebrate biomass were exceeded, but were not significantly different to those at reference locations. Invertebrate abundance reached only 61% of the target value and decreases resembled those in reference locations. Median grain size and percentage fines in newly created sand habitats were similar to pre-enhancement levels.

The taxonomic composition of benthic assemblages shifted post enhancement. Polychaete worms were characteristic of the assemblage before enhancement while gastropods and bivalve molluscs drove assemblage patterns after enhancement. Polychaetes declined from 76% of all invertebrates before enhancement to 47% after, while molluscs increased from 16% before to 49% after.

Seagrass habitat. Prior to construction, seagrasses off Foreshore Beach had undergone a significant natural decline. Strapweed patches within the footprint of the new boat ramp were transplanted to southern Botany Bay and are now indistinguishable from local plants. Condition of remaining seagrass patches off Foreshore Beach was monitored as was recolonization in the created flushing channel and lower reaches of the estuary.

Three post–construction monitoring surveys have documented a narrow, large bed of Paddleweed containing small patches of Eelgrass and Strapweed that extends off Foreshore Beach in 2-3 m water depth. Small isolated patches of Eelgrass and Strapweed persist at Foreshore Beach. Post-construction conditions are suitable for their survival and larger seagrass beds may be able to re-establish given normal processes of succession. Although numerous patches of the colonising Paddleweed and Eelgrass have been recorded in the flushing channel and in the inner estuary, typically these have not persisted. Turbidity may be limiting light penetration to the deeper parts of the flushing channel and offshore movement of sediments may be smothering seagrasses in the shallower areas of the flushing channel before they can fully establish.

Shorebird populations. Six key species of shorebirds were selected to indicate the success of the rehabilitation project: Bar-tailed Godwit (Lamosa lapponica), Red-necked Stint (Calidris ruficollis), Double-banded Plover (Charadrius bicinctus), Curlew Sandpiper (Calidris ferruginea), Red Knot (Calidris canutus) and Pacific Golden Plover (Pluvialis fulva). Abundance, diversity, health and habitat usage were monitored for these species and compared to target numbers derived from pre-construction data in 2006, as well as counts at reference sites. The frequency and sources of disturbance and observations on predation were recorded in peak and off-peak seasons.

The population of Pacific Golden Plover appears to be responding positively to the works, with the target exceeded in five consecutive seasons. Mean numbers of Double-banded Plover have increased at Penrhyn Estuary throughout both tidal phases, though is yet to meet its target peak count. Bar-tailed Godwit and Red-necked Stint have declined in this period, and there were no sightings of Red Knot or Curlew Sandpiper in the 2015 peak season surveys.

Disturbances to shorebirds in Penrhyn Estuary have been reduced with the completion of the sound barrier around the port side perimeter and exclusion of the public. Predation was high in the peak 2014 season, emphasising the need to control foxes and cats.

Monitoring reports for the PEHEP are available at:

http://www.sydneyports.com.au/sustainability/penrhyn_estuary_rehabilitation/monitoring_and_reporting2

Lessons learned and future directions:

  • Achievement of the desired profile for the site based on modelling and watering of saltmarsh plants in the initial stages likely set the stage for the success in establishing the large tracts of saltmarsh habitat. The initial removal and subsequent maintenance of a mangrove-free estuary, including a floating trash boom is supporting regular weed removal to improve the chances of long-term sustainability.
  • The relatively poorer response of transplanted saltmarsh areas, and those weeded but otherwise undisturbed suggests that for large habitat creation projects, propagating and planting local saltmarsh species is an efficient, appropriate approach the showed good results in the short term.
  • Earth moving works were staged such that the tidal exchange within the inner estuary was never completely blocked. This is likely to be a factor in the rapid reestablishment of benthic invertebrates, whose pattern of succession and composition differs from those reported for similar projects. Together with the improvement of dune sand by the addition of seagrass wrack and river mud, the fundamentals for a sustainable feeding habitat for shorebirds have been laid.
  • Tidal erosion removed a small portion of saltmarsh habitat along the inner estuary margin which was reshaped and repaired without further habitat damage or disturbance to roosting birds. The lesson: despite careful planning, erosive forces can alter habitats unpredictably as created habitats mature, and timely adaptive management is required to rectify damage and reduce further loss.
  • Shorebird populations and invertebrate abundance in the first two years of post-construction monitoring showed a generally positive correlation and similar trajectories of, suggesting that created intertidal habitat provided sufficient prey items to support increased shorebird populations in the longer term, despite considerable variability and failure of both populations to meet some target indicators. The abundance, biomass and community composition of benthic invertebrates in the most recent sampling (November 2014) fell within the range of variation seen in the five previous sampling events, however overall shorebird abundance fell to a minimum. Shorebird observations for the three months up to March 2015 showed an increasing trend, however targets for all but one species (Pacific Golden Plover) have not been achieved.

Comparisons to data from reference locations suggest that some factors may be operating at a range of spatial scales observable along the east coast of Australia. For all but Bar-tailed Godwit they suggest an overall decrease in key migratory species that is not limited to Penrhyn Estuary. Predation (or displacement due to presence of predators) may reduce the population of some shorebirds at some times, but no observations suggest that habitat quality, including roosting habitat and availability of prey items deter or limit the level of shorebird habitat use in Penrhyn Estuary.

Stakeholders and Funding bodies: Port Authority of NSW (Formerly Sydney Ports Corporation) fund and manage all aspects of the project, beginning with EIS studies and construction through to ongoing maintenance and monitoring. NSW Ports provides funding for ongoing maintenance and monitoring. Shorebird monitoring was done by as subcontract to Cardno (NSW/ACT) by Avifauna Research & Services, Email www.avifaunaresearch.com.au

Contact information: Dr Peggy O’Donnell Practice Lead Ecology, Water & Environment, Cardno (NSW/ACT). Tel: +61 2 9496 7700 Mobile +61 422 858 827. Postal PO Box 19, St Leonards NSW 1590. Email peggy.odonnell@cardno.com.au

WATCH VIDEO: Peggy O’Donnell 2014 pesentation to AABR seminar

Subtropical rainforest restoration at the Rous Water Rainforest Reserve, Rocky Creek Dam, 1983 – 2016

Key words: Lowland subtropical rainforest, ecosystem reconstruction, drinking water catchment, continual improvement process.

Introduction. Rous Water is actively engaged in ecosystem reconstruction within the drinking water catchment areas it manages on behalf of the community. The aim of these activities is to improve the functioning of essential natural processes that sustain water quality. The methodology used for rainforest restoration by Rous Water has evolved over time through an ‘adaptive management’ process at Rocky Creek Dam. This adaptive management approach has demonstrated that effective large scale sub-tropical regeneration at Rocky Creek Dam is achieved through complete removal of competing plants. The technique has become known as the Woodford Method and is now being applied at other Rous Water restoration sites.

The Rous Water Rainforest Reserve at Rocky Creek Dam is set in the northern headwaters of the Richmond River catchment, on the southern rim of the Tweed shield volcano. Basalt flows from the volcano have produced nutrient rich Red Ferrosol that supported diverse sub-tropical rainforest ecosystems across the region, until the rainforest was largely cleared for agriculture in the late 19th century. The Rocky Creek Dam site is adjacent to the Big Scrub Flora Reserve, the largest remaining remnant subtropical rainforest in the region. This reserve acts as a reference site for the restoration project (Fig 1).

Figure 1. Detail of the regeneration areas at Rocky Creek Dam, showing the areas treated and the year of the initial works

Figure 1. Detail of the regeneration areas at Rocky Creek Dam, showing the areas treated and the year of the initial works

Clearing of land in the vicinity of Rocky Creek Dam by early settlers commenced in the 1890s, with the cleared lands used for the establishment of dairy farms and a sawmill. In 1949, following acquisition of the site by Rous County Council (now Rous Water) for the construction of a water supply dam, this former farmland had reverted to weedy regrowth characterised by a mosaic of native/exotic grass, Lantana (Lantana camara) and Camphor Laurel (Cinnamomum camphora) which supressed any expansion or recovery of scattered rainforest remnants. Transformation of the site commenced in 1983 when Rous Water became actively engaged in ecosystem recovery by systematically removing weeds that suppressed rainforest regeneration, a practice that continues today.

Rainforest restoration methods. The practices and management tools used in rainforest restoration at the site have been previously described by Woodford (2000) and Sanger et al. (2008). The work method typically involves the systematic poisoning and slashing of weeds to promote recruitment of rainforest plants from the soil seed bank and then to facilitate the growth of suppressed rainforest plants, providing a structural framework for further seed dispersal by wind and, particularly, flying frugivores and thus further colonisation by later phase rainforest trees.

Since 1983, an area of approximately 70 ha has been progressively treated in 1-2 ha blocks using this methodology (refer Fig 1), with progressively diminishing amounts of follow-up treatment needing to be conducted in the treated areas over subsequent years to secure successional progression of the rainforest species.

Use of this method means that, due to recruitment from the seed bank and the use of stags (from dead camphor laurel) as perches for seed dispersing birds, very limited planting has been required on the site. This has preserved the genetic integrity of the Big Scrub in this location.

Results. A total of approximately 70 hectares of weed dominated regrowth has been treated at the Rous Water Rainforest Reserve since commencement in 1983 (Figure 1). This is approximately 35 ha since the report previously published in 2000 and represents approximately 30 % of the Rous Water property at Rocky Creek Dam.

This progressive treatment of compartments of weedy regrowth at Rocky Creek Dam has continued to lead to rapid canopy closure by shorter lived pioneer and early secondary tree species, with a gradual progression to higher proportions of later secondary and primary species with increasing time since treatment. All tree species that are listed as occurring in the reference site are not only now present in the restoration area, but informal observations suggest that most, if not all, are increasing in abundance over time (Figs 2-6)

Figure 2. Treated regrowth at the Rous Water Rainforest Reserve, Rocky Creek Dam After 1 year (foreground)

Figure 2. Typical regeneration of rainforest species 1 year after Lantana removal at the Rous Water Rainforest Reserve, Rocky Creek Dam (foreground).

Figure 3. Same photopoint after 6 years

Figure 3. Typical recovery after 6 years

Figure 4. Same photopoint after 12 years

Figure 4. Typical recovery after 12 years

Figure 5. Same scenario after 20 years

Figure 5. typical recovery after 20 years

Figure 6. After 30 years

Figure 6. Typical recovery after 30 years

The structure of the older treated regrowth areas sites appears to be converging on rainforest conditions, as noted by Kanowski & Catterall (2007). Thackway & Specht (2015) depict how 25 ha of systematically treated compartments that were covered almost entirely with lantana are progressing back towards the original Lowland Subtropical Rainforest’s composition, structure and ecological function (Fig 7). Overall the vegetation status in this area was assessed at between 85% and 90% of its pre-clearing status.

This process is, at its oldest 33 years old and in some locations much younger. So it is clear that the development of the subtropical vegetation still has many decades, possibly centuries, to go, before it approaches the composition, structural and habitat characteristics of a primary forest. Notwithstanding the large areas of natural regrowth that are yet to be worked, it is evident that a large proportion of the assisted regeneration areas progressively worked by Rous over the past 33 years now requires only a low level of ongoing maintenance. This shows that these sites are maturing over time and have largely reached a self-organising state, and in the fullness of time will achieve a high degree of similarity to the reference state.

Fig 7, Thackway fig rocky creek dam1

Figure 7. Assessment of change in indicators of vegetation condition in a 25 ha area. This depicts the degree of recoveery of Lowland Subtropical Rainforest found at Rocky Creek Dam, Big Scrub, NSW against a pre-clearing reference. (Graph reproduced with permission. The method used to generate the graph is described in Thackway, R. and Specht, A., (2015). Synthesising the effects of land use on natural and managed landscapes. Science of the Total Environment. 526:136–152 doi:10.1016/j.scitotenv.2015.04.070. ) Condition indices for transition Phase 4 were derived from prior reports including Sanger et al. 2008 and Woodford 2000. Metadata can be viewed at http://portal.tern.org.au/big-scrub-rocky-queensland-brisbane/16908 .

Lessons learned. Using this method of harnessing the natural resilience processes of the rainforest, we have been able to progress the recovery of an important water catchment area, restoring very high biodiversity conservation values in a landscape where rainforest was, and remains, in serious decline., The ability of the high resilience sites at Rocky Creek Dam to respond to the Woodford Method is clearly demonstrated, but there is ample evidence that application of this and similar resilience-based rainforest restoration methods can harnessed resilience at other sites in the Big Scrub that are at greater distances from remnants.

Figure 8. Distribution of management intensity classes across the Rous Water Rainforest Reserve at Rocky Creek Dam.

Figure 8. Distribution of management intensity classes across the Rous Water Rainforest Reserve at Rocky Creek Dam. (Legend for this map is in Appendix 1)

Current work and future directions. Work continues at the site and management is supportive of-site evaluation to assess the extent to which the treated areas are undergoing successional development using a range of available assessment tools.

To assist future planning, and in order to address the issue of how to best estimate and plan for restoration works and associated costs, Rous Water has adapted the methodology developed on the Tweed-Byron Bush Futures Project, where each restoration site/area was assigned a Management Intensity Class (MIC) based on a generalised assessment of site condition, weed composition and cover and other management requirements. (Fig 8) The MIC describes the frequency of restoration work required to restore the site to a minimal maintenance level and how many years this would take to achieve. The MIC aims to describe the extent of management intervention necessary to restore the site to a minimal maintenance level. For this analysis this equates to the establishment of a self sustaining sub-tropical rainforest buffer zone. Each management intensity class is associated with a particular restoration trajectory/cost per hectare, based on visitation frequency by a standard 3 person team and expressed in terms of number of visits required to control / manage weeds. Appendix 1 below shows details of the MIC classification, showing for each class, relevant site criteria, and the estimated level of bush regeneration resources required to bring each class to a low maintenance level.

Contact: Anthony Acret, Catchment Assets Manager,  Rous Water. Tel: +61 (0) 2 6623 3800, Email: anthony.acret@rouswater.nsw.gov.au

Appendix 1. Legend for Management intensity classes used in Fig 8. (From Tweed-Byron Bush Futures)

Appendix 1. Legend for Management intensity classes used in Fig 8.

Recovering biodiversity at Trust for Nature’s Neds Corner Station, Victoria

Doug Robinson, Deanna Marshall, Peter Barnes and Colleen Barnes

Key words. Private conservation area, natural regeneration, ecological restoration, rabbit control.

Introduction. Neds Corner Station is Victoria’s largest private conservation property. This 30,000 hectare ex-sheep and cattle station was purchased for nature conservation by Trust for Nature (Victoria) in 2002.

The property occupies the driest area of the state with an average annual rainfall of only 250 mm. As such, it has strong ecological links to the arid regions of Australia and Australia’s rangelands. Neds Corner sits strategically at the hub of an extensive network of public and private conservation lands bordering or close to the Murray River in Victoria, New South Wales and South Australia. The reserve is bordered on three sides by the Murray Sunset National Park and borders frontages along the Murray River and associated anabranches for more than thirty kilometres, where the River Red Gum (Eucalyptus camaldulensis) dominated riparian zone connects with Chenopod Shrublands, Semi-arid Chenopod Woodlands and Chenopod Mallee Woodlands. Trust for Nature’s restoration efforts are targeted at restoring woodland connectivity across the property to improve habitat extent and condition for woodland and mallee plants and animals, including the nationally threatened Regent Parrot (Polytelis anthopeplus). A biodiversity survey in 2011 found 884 native species at Neds Corner Station, including 6 threatened birds and animals, 77 threatened plants, and 21 species new to science. Trust for Nature continues to find new records for the property.

Fig 1 Neds 2003

Fig. 1. Highly degraded area (near watering points) in 2003 just after Trust purchased the property.

 

Fig 2 Neds 2011

Fig. 2. Same photopoint in 2014 showing extensive natural regeneration of Low Chenopod Shrubland after removal of livestock and extensive treatment of rabbits.

 

Planning for recovery. In 2002, when Trust for Nature first took on the property, the land was severely degraded from continuous over grazing by stock, rabbits and native herbivores; weed infestations; historic clearing of extensive areas of woodland for firewood and forage; and lack of flooding. Native vegetation was sparse over much of the property, soil erosion was extensive and the floodplain and semi-arid woodlands were all showing signs of extreme stress.

In the early years of ownership, management focussed on addressing the most obvious of these threats, with a focus on rabbit control and weed control. In 2010, with funding support from The Nature Conservancy, Trust for Nature prepared a Conservation Action Plan for the reserve, using the Open Standards for Conservation process, and a subsequent management plan. These planning documents identified the key biodiversity values on the reserve, the major threats to these values and the strategies to reduce threats and improve condition to achieve agreed ecological goals.Fig 6 Neds

Fig. 3. Dune Wattle (Acacia ligulata) natural regeneration after cropping was discontinued.

Fig 7 Neds

 Fig 4. Hop Bush (Dodonaea viscosa) natural regeneration after cropping ceased.

Works undertaken. Trust for Nature’s first action was to remove the livestock to allow the regeneration and growth of native vegetation. Stock fencing was decommissioned to enable free movement of native fauna, and new exclosure fencing to protect sites of cultural and ecological significance were also constructed. Major efforts were made to reduce rabbit numbers through the use of warren ripping, fumigation and 1080 baiting across the property. To date, over 20,000 warrens have been treated. Direct seeding and tubestock planting in the Semi-arid Woodland areas of the property have been continuous, with the cessation of a cropping licence, over 500 ha direct seeded in one year as part of an Australian Government funded project. In partnership with the Mallee Catchment Management Authority, environmental water allocations have been used to inundate areas of Neds Corner, providing a vital lifeline to many of the plants and animals that inhabit the riverine billabongs and floodplain forests. Artificial water points and superfluous tracks have been closed. Targeted fox and other feral animal programs are continuous.

Fig 3 Neds 2003

Fig 5. Highly degraded ‘Pine paddock’ in 2003 just after the Trust purchased the property.

Fig 4 Neds 2011

Fig 6. Pine paddock from same photopoint in n2014 after exclosure fencing, rabbit control and extensive direct seeding of trees and shrubs in 2007 (and again in 2010). The grasses all naturally regenerated.

Results. In the 14 years since domestic stock removal and the ongoing control of rabbits and weeds, there has been a dramatic increase in the cover of native vegetation, notably from natural regeneration (Figs 1-4) but also from extensive supplementary planting and direct seeding (Figs 5-8). In 2011, wide spread natural germination of Murray Pines occurred across the woodland sections of the property and Sandhill Wattle (Acacia ligulata) seedlings were observed on one rise where no parent plant was known to occur, indicating a viable seed bank may exist. The vulnerable Darling Lilies (Crinum flaccidum) continue to extend their range, given favourable weather conditions and the continuous control of herbaceous threats to the extent required to ensure adequate recruitment of these key flora species. Bird surveys undertaken for one of the targeted projects within Neds Corner over the past 10 years show an encouraging increase in reporting rates of Brown Treecreeper (Climacteris picumnus victoriae) (>x2 increase), Chestnut-crowned Babbler (Pomatostomus ruficeps) (>x2% increase) and Red-capped Robin (Petroica goodenovii) (>x20 increase).

Fig 5 neds

Fig.7. Revegetation plantings in 2008

Fig 6 NEds 2014

Fig 8. Same revegetation planing line in 2013.

Current and future directions. Trust for Nature are due to revise their CAP and have identified the need to undertake recovery actions at a greater scale. They are currently investigating the feasibility of re-introducing some fauna species back into Neds Corner Station that haven’t been found in the region for decades, provided there is sufficient habitat to sustain them.

Acknowledgements. As a not-for-profit organisation, Trust for Nature (Victoria) relies on the generous support of many individuals, organisations and government entities. The main project partners to date include The Nature Conservancy, RE Ross Trust, Yulgilbar Foundation, Australian Government, Mallee Catchment Management Authority, Parks Victoria, Department of Environment, Land, Water & Planning, Mildura Rural City Council, Northern Mallee Region Landcare, Traditional Owners and the thousands of hours volunteers contribute to Neds Corner Station.

Contact: Doug Robinson, Conservation Science Coordinator, Trust for Nature: (Tel: +61 1800 99 99 33.) Email: dougr@tfn.org.au; www.trustfornature.org.au

Photos: Trust for Nature

 

 

 

Brush pack experiment in restoration: How small changes can avoid leakage of resources and underpin larger scale improvements for restoration and rehabilitation

David Tongway and John Ludwig

Key words: Landscape Function Analysis, biological foci, water harvesting, desertification, erosion

The following experiment illustrates how relatively small changes to redirect water flow can capture water and other biological resources at a restoration site. However the process occurs not only at the micro scale but cumulates to site and landscape scales, making it a primary underpinning principles of a method of site analysis, Landscape Function Analysis (LFA) that has been applied across Australia and other countries to assist land managers counter desertification by redesigning processes that regulate the flow of resources, minimise losses and foster cycling. See http://members.iinet.net.au/~lfa_procedures/

The LFA mindset and methodology involve a purposeful change of focus from listing the biota/ species present or absent at a site, to an examination of the degree to which biophysical processes deal with vital resources with respect to stresses arising from management and climatic events.

Fig 1 before

Fig. 1. Before: bare, crusted, low OC soil, erosion, and high water runoff mainitained by low but persistent, set-stock grazing by sheep and kangaroos.

Fig 2. after treatment

Fig. 2. The restoration treatment was simply to build brush-packs across the contour to trap water, soil and plant litter, slowing overland outflow. This also prevented the grazing down to ~1cm. Grass plants were able to maintain about 10cm of photosynthetic tissue.

Fig 4

Fig 3. After 7 years. Clearly the soil properties have improved the ‘habitat quality’ for the target vegetation.

Fig 5 14 years after

Figure 4. After 14 years, native vegetation re-established.

Fig 3. detail of bushpack after 3 years.

Fig 5. Detail of the brushpack after 3 years showing micro-structures capable of slowing water and accumulating resources.

1. tongway table

ANOTHER KEY OBSERVATION RELEVANT TO RESTORATION AND REHABILITATION

Where resources are not captured or leak out of a system, patchiness will become evident as resources self-organise around foci of accumulation – creating ‘patches’ where resources accumulate and ‘interpatches’ from which they ‘leak’.

The Golden Rule for rehabilitation is: “Restore/replace missing or ineffective processes in the landscape in order to improve the soil habitat quality for desired biota.”

Fig 6. Grassy sward healthy

Fig. 6. A grassy sward patch where the grass plants are close enough together that the water run-off is unable to generate enough energy to redistribute the grassy litter, which is evenly distributed. (The slope is from top to bottom in the image.)

There is also no evidence of sediment transport (not visible in this image). This is because of the tortuous path and short inter-grass distance. It would be possible to derive the critical grass plant spacing for “sward” function in any landscape, taking into account slope, aspect and soil texture.

Fig 7. Grassland in patch-interpatch mode, due to exceeding the critical runoff length for erosion initiation. (Slope is from top to bottom.)

Note that litter and sediment have both been washed off the inter-patch and have been arrested by a down-slope grass patch. Note the orientation of the grassy litter strands.

 

 

 

 

 

 

 

 

 

 

 

 

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

Deanna Rokich

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

Figure 1. Examples of undisturbed Banksia woodland reference sites.

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

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

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

Fig2d

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

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

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

The integration of key research areas has resulted in:

  • Identification of first year species re-instatement being the blueprint for long-term species re-instatement.
  • Observation of cryptic soil impedance and extremely high plant loss in the standard ‘topsoil over overburden’ profile during the 2nd summer following restoration, but higher plant re-instatement and better ecosystem dynamics in the long term.
  • Improvement in seedling re-instatement, illustrated by perennial species return increasing from less than 10% to more than 70% (i.e. >100 perennial species), and stem density return of >140 perennial plants per 5m2 in Year 1, primarily due to improved topsoil handling methods – i.e. good quality, fresh and dry topsoil.
  • A ten-fold increase in the stem density of seedlings derived from direct-seeding due to innovative seed coating technology, delivery to site technology and sowing time optimisation.
  • Trebling of seedling recruitment success due to application of smoke technology.
  • Minimised weed invasion through the use of good quality and fresh topsoil, burial of the weed seedbank and prompt active weed management.
FIg3a

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

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

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

Post-sand extraction restoration practices now involve:

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

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

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

Contact: Deanna Rokich – Deanna.Rokich@bgpa.wa.gov.au

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

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

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

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

Image 3 - Adding structural timber to Oakey Creek

Fig 1. Adding structural timber to Oakey Creek

Image 4 - Installing a fish hotel into Oakey Creek

Fig 2. Installing a fish hotel into Oakey Creek

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

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

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

Image 5 - Wainui crossing before the fishway

Fig. 3 Wainui crossing before the fishway

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

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

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

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

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

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

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

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

Image 1 - Myall Creek prior to restoration

Fig 5.  Myall Creek prior to restoration

Image 2 - Myall Creek after restoration

Fig 6. Myall Creek after restoration

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

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

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

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

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

 

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

READ MORE:

Finbox demonstration reach toolbox: http://www.finterest.com.au/finbox-a-demonstration-reach-toolbox/

Native Fish Strategy – first 10 years. http://onlinelibrary.wiley.com/enhanced/doi/10.1111/emr.12090

Demonstration reaches – Looking back, moving forward http://onlinelibrary.wiley.com/enhanced/doi/10.1111/emr.12092

Monitoring in demonstration reaches https://site.emrprojectsummaries.org/2014/01/25/establishing-a-framework-for-developing-and-implementing-ecological-monitoring-and-evaluation-of-aquatic-rehabilitation-in-demonstration-reaches/