Otways Threatened Species Forum 2018
From Southern Right Whales and New Holland Mice, to Leafy Greenhoods and Tall Astelia – the stories of the threatened species of the Otways were brought to life at the recent Otways Threatened Species Forum in Geelong on Friday 3 August.
Close to 100 researchers, land managers and community members attended the forum, which aims to ensure that the research being undertaken in the Otways is being effectively communicated between researchers and to those who are managing the land – whether they are landowners and landcarers or public agencies like Parks Victoria.
The abstracts from the day’s talks are available below.
Ongoing studies of Fauna of the Otways – Ass Prof. Barbara Wilson, Deakin University
Two high priority natural assets in the eastern Otway Ranges are two threatened species the New Holland mouse Pseudomys novaehollandiae (Vulnerable EPBC), and the swamp antechinus, Antechinus minimus (Vulnerable EPBC). Long-term studies were conducted on both of the species (1975–2006: Wilson et al). High-density populations of P. novaehollandiae occurred after above-average rainfall but declined precipitously during drought. Wildfire resulted in the extirpation of some populations. Although recorded at ten sites it was last recorded in 2003. Local extinctions of A. minimus occurred after the 1983 wildfire with recolonisation taking 20 yrs. Following a break in studies after 2006 the status of these species remained uncertain. Since 2013 new research supported by Parks Victoria and DEPI (now the DELWP) compared current distributions and populations to long-term data. Live trapping and camera trapping surveys were conducted at 43 sites, 20 where A. minimus was previously recorded and 9 where P. novaehollandiae was recorded. There were no captures of P. novaehollandiae and only 8 individual A. minimus were recorded, at 6 sites (coastal dunes, long-unburnt heathy woodland). Further, capture rates of all mammals was very low in woodland. However, there was higher success in coastal dunes and gullies, indicating that such sites may represent significant mammal refuges. Recovery of the endangered species is unlikely without intensive management, focused on remnant or reintroduced populations, including protection from habitat fragmentation and inappropriate fire regimes.
Refugia for ground dwelling fauna post fire – Tim Doherty, Deakin University
The Spiral Sun Orchid and the Threatened Flora Project – Rani Hunt, Department of Environment Land Water and Planning (DELWP)
The aim of this project was “By 2018, known wild populations of Angahook Pink-fingers, Anglesea Grevillea, Robust Spider Orchid and Spiral Sun Orchid will be stabilised and improved.”
Activities were based on recovery actions and site specific activities for each species, a lot of monitoring was already happening.Location of activities is the Eastern Otways, particularly around Anglesea. Coastal project also included activities for Metallic Sun orchid and Square Raspwort near Port Campbell. Lots of community support and input into the work undertaken. Learnt a lot from the community members.
We met or exceeded all our targets as part of this project. Maintained habitats, but there was some change over time within these habitats that was observed.
- Communication materials such as fact sheets; a presence at the annual ANGAIR wildflower show; YouTube video and Facebook posts; newsletters; presentations about the project work and outcomes.
- A range of monitoring programs: detailed; presence/absence; photopoint; new searches for Grevillea; threat assessments – maintained areas weed free and kept an eye on threats at each site.
- Community connections. We took a collaborative approach and provide support to local community groups – in particular Friends of Eastern Otways and ANGAIR, but also provided support to other groups such as Friends of Point Addis (Velvet Daisy Bush surveys), Trees for Life, Trust for Nature, Deakin and Lorne College work experience students. Green Army assistance. Important to upskill people to help improve processes moving forward.
Anglesea: Thelymitra matthewsii (Spiral Sun Orchid) 4 locations known around Anglesea now. Various different monitoring for this species at the different sites. One site we have a transect and have been monitoring individual plants since 2008. All plants were tagged, now if any flowering plant comes up it gets tagged. Information from Mike Duncan’s report (ARI) – Urgent Actions from BOGA funding. Mike has analysed 10 years of data that has been collected collaboratively with DELWP and community members (Marg, Lance and Helen, Jenny, Alison) Results for 2017 were that 36 flowering plants, 4 of these withered, 12 were grazed off, 20 set seed pods.
Data is telling us:
- Data shows the increase in “unobserved” plants
- Natural fluctuations – some potentially have died, recruitment is happening
- Less flowering plants over time – means less seed pods, less recruitment
- A few years we didn’t cage the plants, more browsing of plants occurred
- Need to continue this monitoring to be able to further understand the trends that are occurring
Evidence-based approach to the conservation of Astelia australiana – Linda Parker & Dr Craig Nitschke, The University of Melbourne
Astelia australiana (Tall Astelia) is a threatened herb endemic to cool temperate rainforests and riparian thickets in the Central Highlands and Otway Ranges. The species has a restricted and fragmented distribution, known to occur at only 15 sites including one site in the Otway Ranges. A. australiana has declined in abundance by 57% over the 20 years since its monitoring began in 1993. The threats that have contributed to this decline include disease (Phytophthora spp.), herbivory by introduced Sambar deer (Rusa unicolor) and wildfire. The biggest threat to population growth is light limitation. A. australiana requires canopy gaps to reproduce and increase plant survivorship. Reproduction occurs through sexual (trioecious) and vegetative pathways at the same time leading to seed production and three new clones. The species is pollinated by insects, birds and mammals, including the Eastern Spinebill (Acanthorhynchus tenuirostris) and Swamp Wallaby (Wallabia bicolor) and its fruit are dispersed by a suite of native birds and mammals including Silvereyes (Zosterops lateralis) and Eastern Pygmy Possum (Cercartetus nanus). The current distribution of A. australiana and its gap dynamic strategy means that its populations are fragmented both spatially and temporally.
We conducted a translocation trial of 54 individuals with 83-89 % survival at the 3 translocation sites (control, locally absent and absent site). The Department of Environment, Land, Water and Planning (DELWP) supported the translocation of a further 200 A. australiana to create three new populations including one in the Otway Ranges. Despite our increased knowledge of the species autecology and how to undertake translocations our understanding of its genetic diversity and gene flow between populations is very limited. Ensuring we have populations with high genetic diversity will be critical for fostering resilience and adaptive capacity to future climates. Our new research collaboration with the Conservation Ecology Centre, Foundation for Australia’s Most Endangered Species and the Royal Botanic Gardens Melbourne will use genetic analysis to determine the genetic diversity and gene flow between A. australiana populations. This research will then be used to inform future translocation and conservation management of this species.
The use of dogs for the detection of threatened species – Emma Bennett, Monash University
Update of Otway Environment Program Parks Victoria –Dale Fuller, Parks Victoria
Otway Ark (Landscape scale predator control) has expanded out to 400 bait sites for fox control in November 2017 across the Otways. Data has been collected through camera monitoring (380 camera sites) and habitat structure monitoring over two of the focal areas with analysis to be undertaken this financial year.
Otway Eden (Landscape scale weed control) has been running since 2004 with a focus on new and emerging weed control, high risk weed containment activities and high risk weeds asset protection weed control activities.
Anglesea BOGA is a weed control project focused on mapping infestations of Sallow Wattle, Boneseed, Bridal Creeper, Coastal Tea Tree and Bluebell Creeper through prioritising control of these species in a tenure blind fashion with the objective of protecting rare and threatened species.
The main objective with these projects is to Maintain or Improve the Otways Diverse Vegetation Communities and Ground Dwelling Mammal Assemblage.
Modelling the impact of invasive predators on native mammals – Bron Hradsky, The University of Melbourne
Red foxes (Vulpes vulpes) pose a significant threat to wildlife, livestock and human across southern Australia. Despite worldwide investment in red fox management, decision-makers lack tools for predicting management efficacy. We have developed a new individual-based modelling framework, FoxNet, which can be used to predict red fox population dynamics, including responses to control and habitat heterogeneity. We customised FoxNet to an Otway scenario to explore the potential effects of the Otway Ark control program on fox populations. As part of our new ARC Linkage project, we will be extending FoxNet to incorporate other species and processes, and conducting field research to verify model outputs.
Fox abundance pre- and post-baiting using genetics to identify individual animals – Mark Le Pla, Conservation Ecology Centre
A key tenet of a successful fox control program is a demonstrated reduction in the abundance and density of foxes after control by land managers, usually in the form of 1080 baiting. Unfortunately, generating precise and accurate abundance estimates of red fox populations continues to be challenging using conventional techniques such as track counts, live trapping or camera-based approaches. The establishment of the Otway Ark by Parks Victoria in 2016 offered a valuable opportunity to conduct research into the impact of 1080 baiting upon fox populations in the Otways and the efficacy of alternative sampling methodologies. Genetic profiling of DNA isolated from scat collected in baited and unbaited areas before and after baiting commenced has provided valuable insight into the Otway Ark baiting regime in the short-term. This data set is the only currently available measure of baiting effectiveness for this program.
This non-invasive genetic approach revealed a sizable fox population in both treatment (n = 22) and control (n = 17) areas, with large tracts of transect appearing to be dominated by breeding pairs of foxes. Although the consistent detection of several individual foxes 77 days post-baiting is concerning, a downward trend in the abundance of foxes after baiting was observed. Extra surveys in late 2018 will resample this population to further evaluate the effectiveness of the current baiting regime in the medium-term and if deemed necessary, inform any changes to the regime in an adaptive management framework.
Measuring feral cat abundance in the Great Otway National Park – Matt Rees, The University of Melbourne
Feral cats are a major threat to Australia’s native animals. A nationwide model of feral cat density predicts there to be a low number of feral cats occurring in wet habitats, such as the Otway Ranges. However, limited surveys have been conducted in wet forests (with arid and semi-arid regions receiving much more attention). To test the assumption that feral cats at low densities in wet, rugged environments, we surveyed feral cats in the Western Otway Ranges. We deployed 142 motion-triggered camera traps for 2 months during the winter of 2017. More than half of our cameras detected feral cats. Using these images, we then identified individual cats by their unique coat markings. Through spatial mark-resight modelling methods, we estimate that there is around one feral cat occurring in every square kilometre. This is more than 5 times the expected density for this region, and 3 times higher than the expected national average. It is clear that the native animals in the Western Otway Ranges are enduring a high pressure from feral cats. We are currently resurveying these sites to examine how the feral cats responds to the current Otway Ark fox-baiting program.
How diggers respond to the Otway Ark – Zoi Banikos, The University of Melbourne
Digging mammals are important ecosystem engineers in many parts of Australia, but are threatened by foxes and cats. A new broad-scale fox-baiting program (the Otway Ark) aims to protect two of the Otways’ digging species: the long-nosed potoroo Potorous tridactylus, and the long-nosed bandicoot Perameles nasuta.
The University of Melbourne, the Conservation Ecology Centre, and Parks Victoria have partnered to implement in-depth monitoring of the outcomes of the Otway Ark for foxes, cats, and prey species. My Masters research is part of this partnership, and revolves around quantifying how potoroos and bandicoots respond to fox baiting in the western Otways’ complex, wet forests.
Using motion-sensing cameras, we are observing the fine-scale distributions of potoroos and bandicoots. By doing this before and after baiting, in baited and unbaited areas (a before-after control-impact study design), we will be able to measure changes in potoroo and bandicoot populations in response to the Otway Ark. This research will provide fine-scale information about digging mammal populations in the Otways, and feed into adaptive management practices.
MER in relation to fire – Hamish Martin, Department of Environment, Land, Water and Planning
The Victorian Bushfire Monitoring Program is a Statewide Monitoring, Evaluation and Reporting (MER) program delivered jointly by Parks Victoria and DELWP, lead regionally by DELWP Landscape Evaluators. Through a recent restructure, what was the Barwon Otway Bushfire Risk Landscape (BRL) team is now part of the Barwon South West Regional Forest and Fire Planning Team, supporting both the Otway and Far South West Districts.
The MER Program is aligned to two Code of Practice for Bushfire Management objectives (1. Reducing Risk to Life and Property; 2. Maintain or Improve Ecosystem Resilience). Fuel Hazard Monitoring to measure Pre and Post Burn Overall Fuel Hazard and fuel structure. Approximately 250 sites complete in 2017/18, with the aim to have measured data from all burns on the Fire Operations Plan prior to treatment. All planned burns are flown with aircraft to capture visible and infra-red aerial imagery. This is used to accurately map fire severity which describes the impact of burning and inform effectiveness against burn objectives. Fire Severity Mapping is almost complete for 2017/18.
There has been a project underway since 2016 in the Wye River – Jamieson Track fire area and the Wye River – Kennett Wye Jeep Track planned burn to better understand bushfire fuel recovery in the Forest Herb-rich fuel type. This will be a long-term monitoring project that will improve bushfire risk modelling, and as a result decision making.
Ecosystem Resilience monitoring has also been occurring through the Otway’s. Projects include the re-sampling of the existing Otway Hawkeye project sites, to compliment University of Melbourne research and focussed on small mammal response to fire using camera monitoring and habitat structure assessments. Monitoring in the Heathy Woodland area of the Anglesea – Bald Hills Rd planned burn is also being conducted to continue to build fire response data for small mammals and better understand how low intensity and low coverage burning in the heath impacts both bushfire fuels and ecosystem values.
A key focus moving forward is using the historical and recently collected data collected to compliment or replace expert opinion data which is currently used in our species fire response modelling. We also hope to gain funding for a number of additional projects, such as investigating bushfire management in times of ecosystem stress, such as drought, including identifying key areas of refugia within the landscape to protect.
For staff from other agencies, researchers or interested community members I can sometimes be a conduit into FFMVic for things like: data (e.g. Fire history, burn planning, camera and habitat); advice (e.g. Departmental policy, safety, planned burning methods); Resources (e.g. Field staff to provide on-ground support to monitoring); Funding (e.g. If there is available funding and a project that will be mutually beneficial to meet Departmental objectives).
Fuel accumulation in Otway Forests – Sarah McColl-Gausden, The University of Melbourne
Fire ecology in the Otways – Ellen Rochelmeyer, The University of Melbourne
Birds, Fire and Habitat in Heathy Woodlands – Fred Rainsford, La Trobe University
Fire alters landscapes and drives ecological change globally and so is a potential threat to biota. Fire is also a threat to human life and property; therefore, we need to manage fire in the landscape. To do this effectively we need to understand the relationship between fire and biota. A common way in which we understand this relationship is the paradigm of predictive succession such as the post-fire growth stages described for ecosystems throughout Victoria. Growth stage is a proxy for time-since fire, and as ecosystems respond to fire in different ways, we need to understand how time since fire drives the distribution of species in fire-prone ecosystems. We also need to understand the relative importance of other factors, such as habitat structure, that may also shape species distributions. Here I used non-linear regression modelling to determine the number of bird species in heathy woodland that respond to time since or to some aspect of the habitat structure. I also identified the ‘response-type’. I surveyed birds and habitat structure at 38 sites in a chronosequence of 0.5 – 80 years since fire in an area of heathy woodland near Carlisle River. Approximately one third of species responded to time since fire, one third responded only to habitat structure and another third did not respond to any of the variables included. Five response-types were found in species that responded to time since fire. The majority of species preferred long-unburnt sites, one species preferred middle-aged sites and one species preferred younger sites. Time-since fire seems important in shaping the distribution of bird species in heathy woodland; however, species respond in different ways and other elements of the ecosystem, which are not necessarily driven by time since fire, are also important.
Ongoing research of whales of the South West Coast – Mandy Watson, Department of Environment, Land, Water and Planning
Southern Right Whales were almost hunted to extinction at the turn of the last century leaving a population of around 300 in Australian waters by the 1920’s. Although Right Whales were the first to receive international protection from whaling in 1935 they continued to be hunted by Russian Whalers into the 1970’s. An estimated 150,000 Southern Right Whales were killed globally with 60,000 taken from Australian and New Zealand waters between 1790 and 1980. The Southern Right Whale is listed as Endangered nationally and is considered Critically Endangered in Victoria. Genetic studies have identified two sub-populations in Australia; an eastern (whales breeding in Victoria, Tasmania and New South Wales) and a western (whales breeding in South Australia and Western Australia). The current population estimates are 2,900 for the western sub-population (based on aerial surveys conducted since the 1970s) and 250 – 300 for the eastern (based on limited aerial surveys in 2013 and 2014 and population modelling in 2016). The only recognised breeding and aggregation area for the species in eastern Australia is Logans Beach near Warnambool. DELWP maintains long term sightings data-sets for eastern Australia stretching back to the early 1980’s including a photo-identification catalogue of individual whales. Modelling of this data suggests that there is an increase in the number of whales using the south-east Australian coastline, probably driven by the recovery of the western sub-population since photo-identification research has identified that non-calving females move through the east towards the west.. However the modelling found no significant increase in the number of breeding females using the Logans Beach aggregation area. Further research is warranted to understand population size. distribution and connectivity between Australasian sub-populations. DELWP has commenced a study on survival and recruitment of calves born in south-eastern Australia using remotely piloted aircraft systems (RPAS) and expanded it’s photo-identification research program to include citizen scientists. Southern Right Whale researchers around Australia are also about to embark on a national population assessment with funding from the National Environmental Science Program (NESP) Marine Biodiversity Hub due for completion in early 2020.
Outlining upcoming research on bats in the Otways – Sandra Penman, The University of Melbourne