Luciana L. Porfirio

Improving the use of species distribution models in conservation planning and management under climate change

Choice of variables, climate models and emissions scenarios all influence the results of species distribution models under future climatic conditions. However, an overview of applied studies suggests that the uncertainty associated with these factors is not always appropriately incorporated or even considered. We examine the effects of choice of variables, climate models and emissions scenarios can have on future species distribution models using two endangered species: one a short-lived invertebrate species (Ptunarra Brown Butterfly), and the other a long-lived paleo-endemic tree species (King Billy Pine). We show the range in projected distributions that result from different variable selection, climate models and emissions scenarios. The extent to which results are affected by these choices depends on the characteristics of the species modelled, but they all have the potential to substantially alter conclusions about the impacts of climate change. We discuss implications for conservation planning and management, and provide recommendations to conservation practitioners on variable selection and accommodating uncertainty when using future climate projections in species distribution models.

Climate change, conservation and management: an assessment of the peer-reviewed scientific journal literature

Recent reviews of the conservation literature indicate that significant biases exist in the published literature regarding the regions, ecosystems and species that have been examined by researchers. Despite the global threat of climatic change, similar biases may be occurring within the sub-discipline of climate-change ecology. Here we hope to foster critical thought and discussion by considering the directions taken by conservation researchers when addressing climate change. To form a quantitative basis for our perspective, we assessed 248 papers from the climate change literature that considered the conservation management of biodiversity and ecosystems. We found that roughly half of the studies considered climate change in isolation from other threatening processes. We also found that the majority of surveyed scientific publications were conducted in the temperate forests of Europe and North America. Regions such as Latin America that are rich in biodiversity but may have low adaptive capacity to climate change were not well represented. We caution that such biases in research effort may be distracting our attention away from vulnerable regions, ecosystems and species. Specifically we suggest that the under-representation of research from regions low in adaptive capacity and rich in biodiversity requires international collaboration by those experienced in climate-change research, with researchers from less wealthy nations who are familiar with local issues, ecosystems and species. Furthermore, we caution that the propensity of ecologists to work in essentially unmodified ecosystems may fundamentally hamper our ability to make useful recommendations in a world that is experiencing significant global change.

A tool for simulating and communicating uncertainty when modelling species distributions under future climates

Tools for exploring and communicating the impact of uncertainty on spatial prediction are urgently needed, particularly when projecting species distributions to future conditions. We provide a tool for simulating uncertainty, focusing on uncertainty due to data quality. We illustrate the use of the tool using a Tasmanian endemic species as a case study. Our simulations provide probabilistic, spatially explicit illustrations of the impact of uncertainty on model projections. We also illustrate differences in model projections using six different global climate models and two contrasting emissions scenarios. Our case study results illustrate how different sources of uncertainty have different impacts on model output and how the geographic distribution of uncertainty can vary. Synthesis and applications: We provide a conceptual framework for understanding sources of uncertainty based on a review of potential sources of uncertainty in species distribution modelling; a tool for simulating uncertainty in species distribution models; and protocols for dealing with uncertainty due to climate models and emissions scenarios. Our tool provides a step forward in understanding and communicating the impacts of uncertainty on species distribution models under future climates which will be particularly helpful for informing discussions between researchers, policy makers, and conservation practitioners.

Noah's Ark Conservation Will Not Preserve Threatened Ecological Communities under Climate Change

Background Effective conservation of threatened ecological communities requires knowledge of where climatically suitable habitat is likely to persist into the future. We use the critically endangered Lowland Grassland community of Tasmania, Australia as a case study to identify options for management in cases where future climatic conditions become unsuitable for the current threatened community. Methods We model current and future climatic suitability for the Lowland Themeda and the Lowland Poa Grassland communities, which make up the listed ecological community. We also model climatic suitability for the structurally dominant grass species of these communities, and for closely related grassland and woodland communities. We use a dynamically downscaled regional climate model derived from six CMIP3 global climate models, under the A2 SRES emissions scenario. Results All model projections showed a large reduction in climatically suitable area by mid-century. Outcomes are slightly better if closely related grassy communities are considered, but the extent of suitable area is still substantially reduced. Only small areas within the current distribution are projected to remain climatically suitable by the end of the century, and very little of that area is currently in good condition. Conclusions As the climate becomes less suitable, a gradual change in the species composition, structure and habitat quality of the grassland communities is likely. Conservation management will need to focus on maintaining diversity, structure and function, rather than attempting to preserve current species composition. Options for achieving this include managing related grassland types to maintain grassland species at the landscape-scale, and maximising the resilience of grasslands by reducing further fragmentation, weed invasion and stress from other land uses, while accepting that change is inevitable. Attempting to maintain the status quo by conserving the current structure and composition of Lowland Grassland communities is unlikely to be a viable management option in the long term.

Ecosystem greenspots pass the first test

Given climate change projections, the ability to identify locations that provide refuge under drought conditions is an urgent conservation priority. Previously, it has been proposed that the ecosystem greenspot index could be used to identify locations that currently function as habitat refuges from drought and fire. If this is true, these locations may have the potential to function as climate-change micro-refuges. In this study we aimed to: (1) test whether ecosystem greenspot indices are related to vegetation specific gradients of habitat resources; and (2) identify environmental correlates of the ecosystem greenspots. Ecosystem greenspot indices were calculated for two vegetation types: a woodland and a grassland, and compared with in situ data on vegetation structure. There were inaccuracies in the identification of the grassland greenspot index due to fine scale spatial heterogeneity and misclassification. However, the woodland greenspot index accurately identified vegetation specific gradients in the biomass of the relevant framework species. The spatial distribution of woodland greenspots was related to interacting rainfall, soil and landscape variables. The ability to provide information about variation in resources, and hence habitat quality, within specific vegetation types has immediate applications for conservation planning. This is the first step toward validating whether the ecosystem greenspot index of Mackey et al. (Ecol Appl 22:1852–1864, 2012) can identify potential drought micro-refuges. More work is needed to (1) address sources of error in identifying specific vegetation types; (2) refine the analysis and field validation methods for grasslands; and (3) to test whether species persistence during drought is supported by identified greenspots.

Patterns of crop cover under future climates

We study changes in crop cover under future climate and socio-economic projections. This study is not only organised around the global and regional adaptation or vulnerability to climate change but also includes the influence of projected changes in socio-economic, technological and biophysical drivers, especially regional gross domestic product. The climatic data are obtained from simulations of RCP4.5 and 8.5 by four global circulation models/earth system models from 2000 to 2100. We use Random Forest, an empirical statistical model, to project the future crop cover. Our results show that, at the global scale, increases and decreases in crop cover cancel each other out. Crop cover in the Northern Hemisphere is projected to be impacted more by future climate than the in Southern Hemisphere because of the disparity in the warming rate and precipitation patterns between the two Hemispheres. We found that crop cover in temperate regions is projected to decrease more than in tropical regions. We identified regions of concern and opportunities for climate change adaptation and investment.

Projected direct and indirect effects of climate change on the Swift Parrot, an endangered migratory species

Abstract Assessing future changes in the suitability of the climate niche for interacting species across different trophic levels can identify direct and indirect effects of climate change that may be missed using single-species approaches. We use ensembles of species distribution models based on a dynamically down-scaled regional climate model to project the future suitability of climate for the Swift Parrot (Lathamus discolor), its primary food and habitat resources (Tasmanian Blue Gum (Eucalyptus globulus) and Swamp Gum (E. ovata)), and an introduced nest predator, the Sugar Glider (Petaurus breviceps). These results are combined with layers representing mature forest and fire danger to identify locations that may act as refuges for the Swift Parrot from fire, deforestation and predation under baseline and future climates. Almost a quarter of the nesting habitat of Swift Parrots is projected to become climatically unsuitable by the end of the 21st century, but large areas may remain climatically suitable for both Swift Parrots and their food trees. However, loss of forests and the presence of Sugar Gliders are likely to limit the availability of high-quality habitat. Offshore islands that the Sugar Glider is unable to colonise or where future climate is not projected to be suitable for the Sugar Glider may be the only places, in the near future, where the Swift Parrot will be protected from nest predation by this introduced species.

Economic shifts in agricultural production and trade due to climate change

In addition to expanding agricultural land area and intensifying crop yields, increasing the global trade of agricultural products is one mechanism that humanity has adopted to meet the nutritional demands of a growing population. However, climate change will affect the distribution of agricultural production and, therefore, food supply and global markets. Here we quantify the structural changes in the global agricultural trade network under the two contrasting greenhouse gas emissions scenarios by coupling seven Global Gridded Crop Models and five Earth System Models to a global dynamic economic model. Our results suggest that global trade patterns of agricultural commodities may be significantly different from today’s reality with or without carbon mitigation. More specifically, the agricultural trade network becomes more centralised under the high CO2 emissions scenario, with a few regions dominating the markets. Under the carbon mitigation scenario, the trade network is more distributed and more regions are involved as either importers or exporters. Theoretically, the more distributed the structure of a network, the less vulnerable the system is to climatic or institutional shocks. Mitigating CO2 emissions has the co-benefit of creating a more stable agricultural trade system that may be better able to reduce food insecurity.

Changing fortunes: a brief history of CSIRO funding from Treasury and external earnings in CSIRO 1926-2015

The proportion of funds received by the Commonwealth Scientific and Industrial Organisation (CSIRO) from sources other than Treasury, referred to as external earnings, has been used by the Australian government as an indicator of CSIROs engagement with industry and contribution to the economy. Two periods of decline in external earnings in the 1940s and the 1980s were followed by enquiries into the organisations purpose and operation, amendments to CSIROs enabling legislation and introduction of measures to improve industry engagement. After 1988 these measures included a 30% external earnings target. External earnings subsequently rose from 24% of total revenue in 1988/89 to average 36% over the period to 2014/15, peaking at 51% in 2011. Following a review in 2002 the target was removed due to its unintended consequences which included encouraging competition with private industry, placing emphasis on earning capacity over public good and acting as a disincentive to innovation and collaboration.