Australian Island Research Articles

Not so fussy after all: Shark Bay mouse (Pseudomys gouldii) recorded using a range of habitat types on Faure Island

The Shark Bay mouse (SBM; Pseudomys gouldii) was once widespread across south and central Australia. Following European colonisation, SBM declined catastrophically and the only surviving natural population is found on Bernier Island. Several reintroductions of SBM have been attempted but, to date, populations have successfully established on just two Western Australian islands, Faure Island in Shark Bay and North West Island in the Montebello Archipelago. A lack of suitable habitat, particularly dense stands of coastal spinifex (Spinifex longifolius), is thought to have contributed to the failure of the species to establish at some sites. We analysed records of SBM on Faure Island from 2005 to 2023 to assess patterns of detection in different habitat types, including coastal spinifex. SBM were detected in all studied habitat types on Faure Island, suggesting that coastal spinifex may not be essential for the successful reintroduction of the species. Understanding habitat use by SBM on Faure Island may help to inform the selection of future reintroduction sites and the development of future release strategies. This is particularly important in the context of reintroductions to locations within the species’ historical range where coastal spinifex does not occur.

The evolution of Australian island geographies and the emergence and persistence of Indigenous maritime cultures

Australia was first peopled by maritime voyagers who intentionally crossed from Indonesia using watercraft 65,000 years ago. Despite this, the Holocene archaeological record suggests that many Australian islands were abandoned for several thousand years after separation from the mainland, and only visited again in the last few thousand years. The implication is that coastal peoples reintroduced watercraft into their maritime repertoire only in the recent past. Since first-peopling, sea levels have fluctuated over 120 m, transforming the coastlines and offshore island geographies. In this study, we assess Australia's offshore islands over the range of past sea levels, to discover that most of the Australian coastline has far more islands now than at any time in the human past. Australia's island-rich coastlines emerged with the high sea levels of the late Holocene. The existing island geographies of the Pilbara, the Great Barrier Reef, the Bass Strait and the Rottnest Shelf have no Pleistocene equivalents, meaning coastal peoples encountered new maritime opportunities as modern sea level was established (c. 7 ka). We present regional time series, and detailed paleogeographical maps of these changes, produced by a fully reproducible GIS method. We contextualise this in a review of Australian island archaeology, and demonstrate that key exceptions to this geographical trend are the Kimberley and the Torres Strait – which have evidence for earlier and longer continuous island sequences. These exceptions provided the opportunity for regional persistence of Pleistocene seafaring.

A study on green hydrogen-based isolated microgrid

This paper assesses the techno-economic feasibility of a green hydrogen-based microgrid for a remote Australian island. Hydrogen can be used to provide clean energy in areas where large-scale renewable energy sources are not feasible owing to geography, government regulations, or regulatory difficulties. This study not only identifies the appropriate component size for a hydrogen-based microgrid but also provides an economic perspective of decarbonising Thursday Island in Torres Straits, Queensland, Australia. Due to geographical constraints, the green hydrogen production system needs to be distinct from the electrical network. This research shows how to produce green hydrogen, transport it, and generate power at a low cost. The study was performed utilising the HOMER simulation platform to find the least cost solution. The simulation results demonstrate an AU$0.01 reduction in Levelised Cost of Energy compared to the present electricity generation cost which is AU$0.56. The inclusion of a green hydrogen system will potentially minimise CO2 emissions by 99.6% while ensuring almost 100% renewable penetration. The results of this study will also serve as a guide for the placement of hydrogen-based microgrids in similar remote locations around the world where numerous remote energy systems are located close to each other.

Counting the bodies: Estimating the numbers and spatial variation of Australian reptiles, birds and mammals killed by two invasive mesopredators

AbstractAimIntroduced predators negatively impact biodiversity globally, with insular fauna often most severely affected. Here, we assess spatial variation in the number of terrestrial vertebrates (excluding amphibians) killed by two mammalian mesopredators introduced to Australia, the red fox (Vulpes vulpes) and feral cat (Felis catus). We aim to identify prey groups that suffer especially high rates of predation, and regions where losses to foxes and/or cats are most substantial.LocationAustralia.MethodsWe draw information on the spatial variation in tallies of reptiles, birds and mammals killed by cats in Australia from published studies. We derive tallies for fox predation by (i) modelling continental‐scale spatial variation in fox density, (ii) modelling spatial variation in the frequency of occurrence of prey groups in fox diet, (iii) analysing the number of prey individuals within dietary samples and (iv) discounting animals taken as carrion. We derive point estimates of the numbers of individuals killed annually by foxes and by cats and map spatial variation in these tallies.ResultsFoxes kill more reptiles, birds and mammals (peaking at 1071 km−2 year−1) than cats (55 km−2 year−1) across most of the unmodified temperate and forested areas of mainland Australia, reflecting the generally higher density of foxes than cats in these environments. However, across most of the continent – mainly the arid central and tropical northern regions (and on most Australian islands) – cats kill more animals than foxes. We estimate that foxes and cats together kill 697 million reptiles annually in Australia, 510 million birds and 1435 million mammals.Main conclusionsThis continental‐scale analysis demonstrates that predation by two introduced species takes a substantial and ongoing toll on Australian reptiles, birds and mammals. Continuing population declines and potential extinctions of some of these species threatens to further compound Australia's poor contemporary conservation record.

Values and the experience of family care-giving: cultural values or shared family values?

AbstractThe Sociocultural Stress and Coping Model focuses on the role of cultural values in shaping the stress and coping process for family care-givers of frail older adults. The literature suggested ethnic group-specific values as influences. The current study explored care-givers’ perceptions of values influencing caring to identify values not addressed in quantitative studies of cross-cultural care-giving. Seventeen family care-givers from Australian Aboriginal, Romanian-Australian, Pacific Island and white non-immigrant Australian backgrounds participated in semi-structured interviews about their care-giving experience and the role that values played in caring for a frail older adult. Thematic analysis of the interview transcripts led to identification of themes of cultural values of familism and care for frail older adults, religious values of filial piety and religious coping, love, reciprocity and responsibility/obligation. While cultural values influenced family care versus institutional care, religion was a more clearly identified source of values. Care-givers mostly shared values of love, reciprocity and responsibility/obligation rather than endorsing culture-specific values, with potential variations in expression between individualist and collectivist cultures. These findings suggest that the focus on cross-cultural differences may have missed core values shared across cultural groups and underestimated the influence of religion on care-giving values. Future research could focus on these perceptions of care-givers themselves rather than external perceptions of researchers and service providers.

Towards a national platform for Australia’s islands

Islands are important for maintaining a range of biodiversity, cultural and economic values. However, islands around the world face major and complex conservation challenges, often shared across multiple islands. The variety of tenures and uses also means there is a lack of coordination in policy and management. Addressing these challenges requires sharing lessons of success and failure. To facilitate knowledge-sharing, we need to develop common frameworks, platforms, guidelines and legislation to devise, advise and support actions and collaborations aimed to enhance island conservation. These need to consider both human needs and biodiversity, interactions, research, practice, and information sharing across islands. Pathways may include knowledge, data and experience sharing to ensure that cross-State and Territory coordination can disseminate the lessons learned from island projects to island stakeholders and vice versa. We discuss examples of existing organisational management structures that can potentially form the basis for a timely new platform focusing on Australia’s islands. We propose an island alliance be established as a multi-disciplinary platform to improve coordination among Australia’s islands, and to represent Australia’s environmental island challenges and solutions. Such an alliance would aim to bridge island communities, practitioners, managers, researchers and cultural advisors across diverse and complementary spheres along the continuum from biodiversity and ecosystems to people and social entrepreneurship. This alliance would have a mandate to develop national environmental collaborations, research and standards relating to island environments, facilitate business entrepreneurship with complementary outcomes to manage the threats that face Australian islands, and contribute to improving biodiversity conservation outcomes. The platform would draw together practitioners, natural and social scientists, policymakers, and importantly indigenous and non-Indigenous island communities to lead innovative collaborations and support Australian islands.

How do we drive a renaissance for national island conservation in Australia?

Australia’s approach to managing and conserving its offshore islands as important national assets warrants urgent review. There is a growing realisation that the current trajectory of loss of natural heritage on islands must be reversed, particularly in an era of increasing climate change. We propose a role description and an organisational model for a national Australian Islands Alliance that champions conservation action, prioritises investments aligned to risks, and that connects partners at a strategic national level. A national alliance offers important opportunity to assess threats and report on condition. Four key foundations underpin a national alliance dedicated to championing island care and expert management: (1) management informed by evidence; (2) sound return on investment; (3) national coordination in partnership with States and Territories; and (4) community participation inclusive of Aboriginal peoples’ and Torres Strait Islanders’ custodial rights and interests. The message from experiences shared across Australia, New Zealand and the Pacific region is that traditional island custodians and stakeholders are vital partners to restoration efforts. These shared learnings collectively demonstrate the time is now for Australia to move forward with a respectful and unified direction to progress successful and sustainable island conservation and restoration.

Island Mammal Extinctions are Determined by Interactive Effects of Life History, Island Biogeography, Mesopredator Suppression

Island Mammal Extinctions are Determined by Interactive Effects of Life History, Island Biogeography, Mesopredator Suppression

Options and rationale for regional property‐based kangaroo production

SummaryThe larger kangaroos (Macropus giganteus, M. fuliginosus and Osphranter rufus) are widely distributed and have a national population which fluctuates in response to changes in grass growth and trends to 40 million. Most are outside parks and reserves and, on pastoral properties, particularly on the rangelands of southern Australia. High numbers compromise regenerative agriculture, pasture conservation, revegetation and stewardship programmes, and can have significant financial impacts on landholders by lowering livestock production and damaging sustainability. Some smaller macropods, wallabies and pademelons, also have a similar effect, especially in Tasmania and on other smaller Australian Islands where foxes are absent. Paradoxically, kangaroos have a wide range of potentially valuable production attributes and are unique, which should be a global comparative advantage. The kangaroo industry is established with a small domestic and international market, although demand has been falling in recent years. Non‐commercial culling is rising, which results in millions of carcasses being wasted and left to decompose in the field. Indigenous communities abhor such waste and its cultural implications. A stronger kangaroo industry would be a better solution to managing overabundant kangaroos than pest culling and exclusion fences. Because kangaroos move from property to property, populations need to be managed on a regional basis through ‘regional property‐based kangaroo production’. A form of proprietorship over this mobile resource would encourage landholders to play a role in creating greater demand for kangaroo products. They would have an incentive to raise the value of kangaroos. Through innovative harvesting, they could deliver high‐quality, environmentally branded, accurately described, gourmet, differentiated products integrated with other livestock industries. They could establish cooperatives and embark on promoting regional kangaroo products. Policy improvements are needed to achieve these production systems. Doing so would diversify their enterprises, convert a liability already on their properties into an asset, create employment, enhance rural economic resilience, and improve animal welfare and conservation outcomes while earning them carbon credits. These opportunities become even more profound as climate change progresses.

The intrusion of polluted Fly River mud into Torres Strait

There is a concern that the Fly River plume from Papua New Guinea (PNG) may be delivering mine-derived polluted mud along the southern PNG coast into the northern Torres Strait, which is the northernmost extent of the Great Barrier Reef. To quantify this threat, the mud transport dynamics along the southern PNG coast were studied using the SLIM model. The model was qualitatively verified using historical field data on sediment dynamics and compared with more recent satellite-derived turbidity data. During strong south east winds and spring tides, about 5.4% of the Fly River mud discharge enters the Torres Strait, in agreement with previous field-derived results. The annual net movement of mud is westward, thus polluted Fly River mud progressively intrudes into Torres Strait. This intrusion is slow and may take a century to reach in significant quantities at Saibai Island, the nearest Australian island to the Fly River. Field data are needed to fully validate the model and provide greater confidence in these results.

Review of the reporting of ecological effects of rodent eradications on Australian and New Zealand islands

Island species are susceptible to invasive mammals because of their small populations, specialised habitats and reduced likelihood of recolonisation. For more than 50 years, invasive mammals have been eradicated from islands around the world. Despite the success of eradications, there are few publications in the primary literature detailing the ecological benefits and consequences of these eradications. Here we conduct a review of the published literature focussing on rodent eradications conducted on Australian and New Zealand islands and we evaluate the extent of reporting of non-target mortality and ecological monitoring following an eradication. A search of the Database of Island Invasive Species Eradications website identified that successful, whole-island rodent eradications were conducted on 66 Australian and 124 New Zealand islands in the period from 1964 to 2016. We found that non-target mortality was rarely ever reported (3% and 12% for eradications on Australian islands and New Zealand islands, respectively). Results of any quantitative ecological monitoring following eradications were published for only 10% of all successful rodent eradications on Australian islands and 19% of all eradications on New Zealand islands. There also has been no change in reporting of potential benefits and consequences of rodent eradications in Australia and New Zealand over the last few decades despite an increased awareness of the problem of under-reporting. We discuss the detailed benefits and consequences of these eradications in Australia and New Zealand and highlight the need to incorporate ecological monitoring into new projects to document benefits and consequences of eradications to inform future eradications.

A potential model for assessing and adapting island biodiversity to the risks of climate change

Context Island landscapes and component biodiversity provide invaluable services. However, these are threatened by climate change. There is currently no framework for assessing and mitigating such threats on islands. Aims Based on an existing adaptation standard, we aimed to propose a systematic approach for planning the adaptation of islands based on a risk management process. Methods For each risk, we investigated a range of adaptation approaches that can be considered and selected by conservation practitioners in designing conservation interventions. Key results For each risk identified, a range of adaptation measures can be selected: do nothing; maintain and enhance habitat, intensive species management, and preserve populations (including through ex situ conservation); or exploit the natural characteristics of islands to conserve biodiversity. Conclusions This approach provides a decision-making matrix of risks/drivers vs adaptation measures to assist in the design of conservation interventions, which can be applied to Australian islands on a priority basis. Implications There will inevitably remain gaps in knowledge and understanding that will hamper conservation efforts. There will also remain circumstances where adaptation is not possible and loss of services and biodiversity will follow as a result of climate change. However, the proposed model for assessing and adapting to climate change risks is a step forward from the current situation, where relatively little consideration is being given to climate change when developing island conservation interventions.

Combining participatory action research with sociological intervention to investigate participatory place branding

PurposePlace branding research has recently focused on developing more inclusive models to better capture the co-creation of place identities. This paper aims to investigate stakeholder communication interactions in place branding processes to inform alternative, participatory, network governance models of stakeholder engagement.Design/methodology/approachThe literature on stakeholder engagement in place branding processes is sparse. Through a regional case study of the Australian island state of Tasmania, the paper combines participatory action research (PAR) with the method of sociological intervention (SI) to investigate how participants individually and collectively reflect on their practices and patterns of engagement.FindingsBy combining PAR with SI, participants were enabled to gain a greater appreciation of how cooperation and collective self-reflection enhance effective place branding practices. Furthermore, by facilitating participants to compile a list of impediments to collaboration, the research informs efforts to develop more inclusive governance models for place branding. Finally, the PAR/SI method itself served as a practical tool to encourage enhanced stakeholder engagement in applied settings.Research limitations/implicationsThe approach is based on a single case study in a particular regional context and the findings require replication in other jurisdictions.Practical implicationsPAR/SI is a practical tool to achieve greater stakeholder engagement and enhance collaborative social action through a process of collective, critical reflection in applied settings.Originality/valueThe paper advances understanding of ways to operationalize participatory place branding through more inclusive, multistakeholder governance arrangements.

Species of Heterolepismatinae (Zygentoma: Lepismatidae) found on some remote eastern Australian Islands

Species of Heterolepismatinae (Zygentoma: Lepismatidae) found on some remote eastern Australian Islands

Mass rodent poisoning on this remote Australian island could bring back giant stick insect

Mass rodent poisoning on this remote Australian island could bring back giant stick insect

Review of the batfish genus Halicmetus Alcock, 1891 from Australian waters, with descriptions of two new species (Lophiiformes: Ogcocephalidae).

A taxonomic review of species of the Indo-Pacific batfish genus Halicmetus occurring in the Australian Exclusive Economic Zone is provided. Treatments of six species in the region, including diagnoses of the widespread Halicmetus niger Ho, Endo Sakamaki, 2008, H. reticulatus Smith Radcliffe, 1912 and H. ruber Alcock 1891, a reclassification of the poorly known H. marmoratus Weber, 1913, and descriptions of two new species, H. westraliensis n. sp. (an Australian endemic) and H. drypus n. sp. (from the northern sector of the Australian Exclusive Economic Zone off Norfolk Island). The Australian species can be distinguished from each other and regional congeners by a combination of morphometrics, meristics and colouration. A key is provided for all known species of the genus.

Sequencing the Ant fauna of a Small Island: Can Metagenomic Analysis Enable Faster Identification for Routine Ant Surveys?

All known ant species from a small Western Australian island were subjected to DNA barcoding of the CO1 gene, with a view to using the database to identify ants by Next Generation Sequencing in subsequent, routine surveys. A further aim was to evaluate whether the data could be used to see if any new species had arrived on the island since the total fauna had been inventoried. Of the 125 unique ant species then known from the island, 72 were successfully barcoded. Those that were refractory to amplification were largely the result of sample age and/or contamination. Following this base-line barcoding, ants were sampled from 14 regular sampling sites and ant sequences were obtained from the bulked ‘metagenomic soup’. Prior to doing this, a parataxonomist had identified all ant species in the samples and returned them to the ‘soup’. Successful identification for each site varied from 38% (Sites 12 and 27) to 100% of species (Site 10). Comparison of the number of species recovered with the number of sequences obtained from each sample showed a positive correlation between the two variables. When a site had >1,000 sequences, the average recovery rate was 79%, which is in contrast to the lowest four recovery rates (Site samples 12, 22, 26 and 27), which had fewer than 440 amplicon sequences. The ability to detect individuals that occur at low frequencies is also important. We analysed each site individually to determine if a species was detected and how that related to the proportion of individuals in the pooled sample. Where a species was present at <4% of the total sample, it was only detected 10% of the time, indicating that adequate sequencing depth is critical to species recovery. We conclude that this technique was only partially successful in replacing conventional taxonomy and that it could have limited ability to detect incursions unless the new arrival is abundant. Current barcoding is no longer limited to the CO1 gene and other genes are characterised for identification of intractable groups where CO1 does not provide appropriate levels of resolution.

The Australian Museum Lord Howe Island Expedition 2017—freshwater fishes

The Australian Museum Lord Howe Island Expedition 2017—freshwater fishes

Critical Success Factors for Peak Electricity Demand Reduction: Insights from a Successful Intervention in a Small Island Community

This paper examines a successful residential peak electricity demand reduction project which employed a multi-disciplinary approach. The purpose of this study was to examine the critical success factors necessary for reducing peak demand and total energy consumption in a small Australian island community. This case study research is based on qualitative data obtained from semi-structured, in-depth interviews with residents from 22 households. It is proposed that the results of the examined project are transferable to other communities if the utility is able to develop the necessary trust, access, influence, and partnership with residential consumers required to create the environment for electricity demand reduction success. Findings from this research highlight the potential approach for future policymaking aimed at reducing peak electricity demand and total energy consumption in multiple communities, thus helping achieve government low carbon targets while reducing infrastructure spending.

Simulating the effectiveness of prescribed burning at altering wildfire behaviour in Tasmania, Australia

Prescribed burning is a widely accepted wildfire hazard reduction technique; however, knowledge of its effectiveness remains limited. To address this, we employ simulations of a widely used fire behaviour model across the ecologically diverse Australian island state of Tasmania. We simulate three broad scenarios: (1) no fuel treatment, (2) a maximal treatment, with the most possible prescribed burning within ecological constraints, and (3) 12 hypothetically more implementable state-wide prescribed-burning plans. In all simulations, we standardised fire-weather inputs to represent regionally typical dangerous fire-weather conditions. Statistical modelling showed that an unrealistically large maximal treatment scenario could reduce fire intensity in three flammable vegetation types, and reduce fire probability in almost every vegetation type. However, leverage analysis of the 12 more-realistic implementable plans indicated that such prescribed burning would have only a minimal effect, if any, on fire extent and that none of these prescribed-burning plans substantially reduced fire intensity. The study highlights that prescribed burning can theoretically mitigate wildfire, but that an unrealistically large area would need to be treated to affect fire behaviour across the island. Rather, optimisation of prescribed burning requires careful landscape design at the local scale. Such designs should be based on improved fire behaviour modelling, empirical measurement of fuels and analysis of actual wildfires.