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Darwin, Australia

Liu D.L.,Wagga Wagga Agricultural Institute | Liu D.L.,Graham Center for Agricultural Innovation | Timbal B.,Center for Australian Weather and Climate Research | Mo J.,Primary Industry | Fairweather H.,Industry and Investment
International Journal of Climate Change Strategies and Management

Purpose: The purpose of this paper is to develop a geographic information system (GIS)-based risk assessment tool for visualising climate change impacts in agricultural industries and evaluating eventual adaptation strategies. Design/methodology/approach: A climate change adaptation strategy tool (CCAST) with built-in GIS capability has been developed for agricultural industries. Development of the GIS functionality within CCAST includes the implementation of map projection, boundary allocation, interpolation and a graphical display of spatial data. In total, 20 climatic and crop indices are computed alongside basic climate variables (rainfall and temperature) from downscaled global climate models at 1,062 sites across the state of New South Wales (NSW) located in eastern Australia. Findings: A case study in Australia is used to demonstrate use of this tool. This shows selecting suitable genotypes of wheat is a key adaptation strategy to mitigate the impacts of climate change on wheat cropping. It shows that spring wheat genotypes will become predominate, while the winter genotypes will only be viable in clearly defined areas where sufficient days of cool temperature exist for completion of vernalisation in a future warmer climate. Originality/value: CCAST integrates knowledge relevant to climate impact management in a stand-alone environment. It benefits from statistical analysis and GIS functionalities and provides many user-friendly GIS features to make it suitable for practitioners on the ground. © Emerald Group Publishing Limited. Source

Heupel M.R.,Australian Institute of Marine Science | Knip D.M.,James Cook University | de Lestang P.,Primary Industry | de Lestang P.,Jacobs Engineering | And 2 more authors.
Aquatic Biology

Despite a broad Indo-Pacific distribution, the movement patterns of barramundi Lates calcarifer have gone largely unstudied, particularly in freshwater systems. This study examined the short-term movement and dispersal patterns of 60 barramundi in a seasonally closed freshwater system in 2 seasons (warm and cool). Data indicated that individuals generally moved small distances during up to 18 d of monitoring and that size was not a factor in movement patterns. Individuals moved farther and had larger activity spaces in the cool season than in the warm season, indicating different behavior between seasons in this freshwater habitat. However, in both seasons, individuals remained in the permanently flooded sections of the billabong with limited movement into seasonally flooded regions. Further examination of long-term presence and movements of freshwater barramundi populations is required, but these data provide insight into short-term movements in a freshwater system. © Inter-Research 2011. Source

Brown C.J.,University of Queensland | Brown C.J.,CSIRO | Fulton E.A.,CSIRO | Hobday A.J.,CSIRO | And 16 more authors.
Global Change Biology

Climate change is altering the rate and distribution of primary production in the world's oceans. Primary production is critical to maintaining biodiversity and supporting fishery catches, but predicting the response of populations to primary production change is complicated by predation and competition interactions. We simulated the effects of change in primary production on diverse marine ecosystems across a wide latitudinal range in Australia using the marine food web model Ecosim. We link models of primary production of lower trophic levels (phytoplankton and benthic producers) under climate change with Ecosim to predict changes in fishery catch, fishery value, biomass of animals of conservation interest, and indicators of community composition. Under a plausible climate change scenario, primary production will increase around Australia and generally this benefits fisheries catch and value and leads to increased biomass of threatened marine animals such as turtles and sharks. However, community composition is not strongly affected. Sensitivity analyses indicate overall positive linear responses of functional groups to primary production change. Responses are robust to the ecosystem type and the complexity of the model used. However, model formulations with more complex predation and competition interactions can reverse the expected responses for some species, resulting in catch declines for some fished species and localized declines of turtle and marine mammal populations under primary productivity increases. We conclude that climate-driven primary production change needs to be considered by marine ecosystem managers and more specifically, that production increases can simultaneously benefit fisheries and conservation. Greater focus on incorporating predation and competition interactions into models will significantly improve the ability to identify species and industries most at risk from climate change. © 2009 Blackwell Publishing Ltd. Source

Macbeth G.M.,University of Queensland | Broderick D.,University of Queensland | Ovenden J.R.,University of Queensland | Buckworth R.C.,Primary Industry
Theoretical Population Biology

Genotypes produced from samples collected non-invasively in harsh field conditions often lack the full complement of data from the selected microsatellite loci. The application to genetic mark-recapture methodology in wildlife species can therefore be prone to misidentifications leading to both true non-recaptures' being falsely accepted as recaptures (Type I errors) and true recaptures' being undetected (Type II errors). Here we present a new likelihood method that allows every pairwise genotype comparison to be evaluated independently. We apply this method to determine the total number of recaptures by estimating and optimising the balance between Type I errors and Type II errors. We show through simulation that the standard error of recapture estimates can be minimised through our algorithms. Interestingly, the precision of our recapture estimates actually improved when we included individuals with missing genotypes, as this increased the number of pairwise comparisons potentially uncovering more recaptures. Simulations suggest that the method is tolerant to per locus error rates of up to 5% per locus and can theoretically work in datasets with as little as 60% of loci genotyped. Our methods can be implemented in datasets where standard mismatch analyses fail to distinguish recaptures. Finally, we show that by assigning a low Type I error rate to our matching algorithms we can generate a dataset of individuals of known capture histories that is suitable for the downstream analysis with traditional mark-recapture methods. © 2011. Source

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