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Despite its remoteness, the vegetation of Subantarctic Macquarie Island is amongst the most thoroughly surveyed and monitored in Australia. Eradication of invasive European rabbits was achieved in 2011, after a decline in introduced rabbit populations in the eighties and nineties and a resurgence in the early twenty‐first century. The impacts of introduced rabbits and climate change on the vegetation of Macquarie Island are well‐documented from long‐term plots situated in some, but not all, of the vegetation types. Satellite data are sporadic, with substantial could‐free coverage rare. The island has been well‐photographed over many years, and several series of long‐term photo‐monitoring sites have been established over the past few decades. We compared insights on vegetation change derived from repeat landscape photography three years after myxoma virus was established, rabbit population resurgence and rabbits eradication, with plant species cover data from a set of long‐term monitoring sites, and with spectral vegetation indices derived from satellite imagery covering the transition from high rabbit numbers to no rabbits. The repeat photography confirmed many well‐documented vegetation trends, as well as providing an indication of previously unreported trends: stability of Acaena herbfield despite reduced disturbance; increase in cover of Pleurophyllum hookeri; increase in short grassland vegetation; and constancy in cover of Azorella macquariensis. Although subject to errors related to differences in sample size and resolution, the rephotography data gave the best information on spatial and temporal patterns of overall vegetation change. The plot data, where comparable, were not fully consistent with the rephotography data and are expensive to collect, requiring scientific expertise in the field and much time, while the sporadically available remote sensing data were effective in monitoring the revegetation/devegetation of ground and the recovery of Poa foliosa but we were unable to detect other changes. [ABSTRACT FROM AUTHOR]

Shark and ray tourism is growing in popularity and often necessitates attractants like bait and chum to encourage close encounters. Such practices remain contentious amongst stakeholders as they may affect the species they target. We used lipid and fatty acid profiles to investigate the effects of South Australia's cage-diving industry on the diet and nutritional condition of white sharks Carcharodon carcharias (n = 75). We found no evidence of dietary shifts or reduced nutritional condition after a >3 week period of tourism-exposed residency at the Neptune Islands where the cage-diving industry operates. White sharks fed on a variety of prey groups, similar to other populations around Southern Australia that are not exposed to ecotourism provisioning. These findings indicate that current cage-diving operations in South Australia do not alter white shark diet and nutritional condition where prey resources are abundant. Image 1 • Previous studies suggest white shark cage-diving changes shark behaviour and daily activity. • Lipids and fatty acids in white shark muscle were used to assess the nutritional effects of the cage-diving industry. • White shark nutrition is unaffected by practices of the cage-diving industry. • White sharks do not consume sufficient bait (tuna) to affect their diet. • White sharks foraging ecology at the Neptune Islands is similar to other locations in South Australia. [ABSTRACT FROM AUTHOR]

Both the public and the scientific perception of an island's value are important in deciding its future, with regard to the levels of access, protection and funding for research. There is a popular belief that the preservation of islands equates to the slightly idiosyncratic conservation of unique remote habitats, where the value of any island is its isolation. However, by understanding how scientists use islands, a different picture emerges; islands may be seen also as integrated, or representative fragments of the world that contribute to biodiversity and scientific theory far beyond their narrow geographical boundaries. Here, we broadly review the full scope of values science places on islands. We resolve four central perspectives by which scientists view islands, based on how islands are incorporated into their research: (i) species-level studies; (ii) island-level studies; (iii) islands as model systems; and (iv) islands as part of a global network. Recognising this diverse value system helps enlarge our understanding of islands and reforges their importance to the public and policy makers. [ABSTRACT FROM AUTHOR]

The ‘disappearing islands’ is a distinct idea that emerged out of the Intergovernmental Panel on Climate Change report to describe the vulnerability of small island states in the Pacific to sea-level rise as a result of climate change. In this article I deploy the ‘disappearing islands’ to map the complex politics of climate change governance. Through various governmental rationalities the ‘disappearing islands’ are operationalized as proof of climate catastrophe; as a means of concretizing climate science's statistical abstractions and as a signifier of the urgency and uneven impacts of global climate change. Drawing on focus group research from the Australian Research Council Linkage project Hot science, global citizens: The agency of the museum sector in climate change interventions, I juxtapose these multifarious governmental perspectives with the views of ordinary citizens in Australia and the United States in relation to the fate of the disappearing islands as a result of developed world consumption choices and carbon-burning practices. I conclude that rhetorical gestures made towards mobilizing a moral and ethical ecological citizenry charged with the responsibility of saving the ‘disappearing islands’ are too simplistic and more difficult to achieve than imagined. [ABSTRACT FROM PUBLISHER]

Coral reefs are threatened ecosystems, so it is important to have predictive models of their dynamics. Most current models of coral reefs fall into two categories. The first is simple heuristic models which provide an abstract understanding of the possible behaviour of reefs in general, but do not describe real reefs. The second is complex simulations whose parameters are obtained from a range of sources such as literature estimates. We cannot estimate the parameters of these models from a single data set, and we have little idea of the uncertainty in their predictions. We have developed a compromise between these two extremes, which is complex enough to describe real reef data, but simple enough that we can estimate parameters for a specific reef from a time series. In previous work, we fitted this model to a long-term data set from Heron Island, Australia, using maximum likelihood methods. To evaluate predictions from this model, we need estimates of the uncertainty in our parameters. Here, we obtain such estimates using Bayesian Metropolis-Coupled Markov Chain Monte Carlo. We do this for versions of the model in which corals are aggregated into a single state variable (the three-state model), and in which corals are separated into four state variables (the six-state model), in order to determine the appropriate level of aggregation. We also estimate the posterior distribution of predicted trajectories in each case. In both cases, the fitted trajectories were close to the observed data, but we had doubts about the biological plausibility of some parameter estimates. We suggest that informative prior distributions incorporating expert knowledge may resolve this problem. In the six-state model, the posterior distribution of state frequencies after 40 years contained two divergent community types, one dominated by free space and soft corals, and one dominated by acroporid, pocilloporid, and massive corals. The three-state model predicts only a single community type. We conclude that the three-state model hides too much biological heterogeneity, but we need more data if we are to obtain reliable predictions from the six-state model. It is likely that there will be similarly large, but currently unevaluated, uncertainty in the predictions of other coral reef models, many of which are much more complex and harder to fit to real data. [Copyright &y& Elsevier]

The article focuses on the need for a comprehensive plan of action for island biosecurity in Australia. It notes on a National Island Biosecurity Initiative to lay the foundations for an effective island biosecurity in protecting populations of migratory species and in preventing the extinction of threatened species in the ecosystem. It also notes on the importance of keeping the natural condition of the Australian islands and the development of a consistent approach to island biosecurity.