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Townsville, Australia

James Cook University is a public university and is the second oldest university in Queensland, Australia. JCU is a teaching and research institution. The University's main campuses are located in the tropical cities of Cairns, Singapore and Townsville. JCU also has study centres in Mount Isa, Mackay and Thursday Island. A Brisbane campus, operated by Russo Higher Education, delivers undergraduate and postgraduate courses to international students. The University’s main fields of research include marine science, biodiversity, sustainable management of tropical ecosystems, genetics and genomics, tropical health care and tourism. Wikipedia.

Pike D.A.,James Cook University
Global Ecology and Biogeography | Year: 2013

To understand whether climate limits current sea turtle nesting distributions and shapes the ecological niche of the terrestrial life-history stage of these wide-ranging marine vertebrates. Location: Coastlines world-wide. Methods: I predicted the spatial distributions of nesting habitat under current climatic conditions for seven sea turtle species using information criteria and maximum entropy modelling. I also compared niche similarity among species using three niche metrics: I, Schoener's D and relative rank. Results: Sea turtles currently nest across their entire bioclimatic envelopes, with up to six species predicted to nest on a single beach. The Caribbean Sea, Gulf of Mexico and Australasia support high nesting diversity, with most regional areas supporting three to five species. Despite large overlap in nesting distributions among species, loggerhead and green turtles have the broadest environmental niches, while Kemp's ridley and flatback turtles have very narrow niches. Main conclusions: The terrestrial nesting habitat of sea turtles is characterized by distinct climatic conditions, which are linked to the physical conditions necessary for eggs to hatch successfully and allow hatchlings to disperse from natal areas. Despite broad geographic patterns of overlap and similar embryonic tolerances to temperature and moisture among species, sea turtles partition habitat by nesting in different niche spaces. The tight link between current geographic patterns of nesting and climate, along with the dependence of developing embryos on nest microclimate, imply that regional or global changes in environmental conditions could differentially influence the distribution of sea turtle species under climate change. This could influence the adaptive potential of different populations, and predicting these responses before they occur will be important in mitigating the effects of climate change. © 2013 Blackwell Publishing Ltd. Source

Zahedi A.,James Cook University
Renewable and Sustainable Energy Reviews | Year: 2011

Many countries around the world are considering using solar energy technologies in their future energy planning. The intermittency and unpredictability nature of solar power generation, which can influence the power quality and reliability of the power grid especially at large-scale solar energy systems, constitute a drawback for use of solar technology. Precise research and investigations are needed to overcome this weakness helping solar power be used in power network in large scale. The variation in sun radiation may lead to over-production of electricity from solar PV generators at one time, and lack of production to satisfy the energy demand at another time. As a result, solar PV systems demonstrate a low-level of reliability in power systems. However, an energy storage technology would play a significant role in increasing the reliability of solar power generation systems. The objectives of this study are: firstly to review the issues in relation to grid-integration of solar PV systems, secondly, to review a range of storage devices that could technically and economically be used in association with solar PV energy in order to increase the solar energy penetration level with appropriate reliability in weak electric systems, and finally to present a model for solar PV system combined with battery and super-capacitor. © 2010 Elsevier Ltd. Source

Laurance W.F.,James Cook University
Trends in Ecology and Evolution | Year: 2013

Although many protected areas are foci for scientific research, they also face growing threats from illegal encroachment and overharvesting. Does the presence of field researchers help to limit such threats? Although evidence is largely anecdotal, researchers do appear to provide some protective effects, both actively (such as by deterring poachers) and passively (such as by benefiting local communities economically and thereby generating support for protected areas). However, much remains unknown about the generality and impacts of such benefits. A key priority is to develop a better understanding of the advantages and limitations of field research for aiding protected areas and their biodiversity. © 2013 Elsevier Ltd. Source

Nott J.,James Cook University
Quaternary Science Reviews | Year: 2011

This study provides the first long-term tropical cyclone record from the Indian Ocean region. Multiple shore parallel ridges composed entirely of one species of marine cockle shell (Fragum eragatum) standing between 3 and 6 m above mean sea level occur at Hamelin Pool, Shark Bay, Western Australia. The ridges record a tropical cyclone history between approximately 500 cal BP and 6000-7000 cal BP. Numerical storm surge and shallow water wave modelling techniques have been applied to determine the intensity (central pressure with uncertainty margins) of the storms responsible for deposition of the ridges, which has occurred approximately every 190-270 years. The ridges also record a 1700 year gap in tropical cyclone activity, between approximately 5400 cal BP and 3700 cal BP, where ridges deposited prior to this time were buried by a substantial deposit of aeolian fine-grained terrestrial sediment. The presence of this sedimentary unit suggests that this 1700 year period was characterised by a very dry climate; possibly the driest phase experienced in this region since the mid-Holocene. The absence of tropical cyclones at this time and the occurrence of this mega-drought may be linked. © 2010 Elsevier Ltd. Source

Phillips B.L.,James Cook University
Proceedings. Biological sciences / The Royal Society | Year: 2013

The virulence of a pathogen can vary strongly through time. While cyclical variation in virulence is regularly observed, directional shifts in virulence are less commonly observed and are typically associated with decreasing virulence of biological control agents through coevolution. It is increasingly appreciated, however, that spatial effects can lead to evolutionary trajectories that differ from standard expectations. One such possibility is that, as a pathogen spreads through a naive host population, its virulence increases on the invasion front. In Central America, there is compelling evidence for the recent spread of pathogenic Batrachochytrium dendrobatidis (Bd) and for its strong impact on amphibian populations. Here, we re-examine data on Bd prevalence and amphibian population decline across 13 sites from southern Mexico through Central America, and show that, in the initial phases of the Bd invasion, amphibian population decline lagged approximately 9 years behind the arrival of the pathogen, but that this lag diminished markedly over time. In total, our analysis suggests an increase in Bd virulence as it spread southwards, a pattern consistent with rapid evolution of increased virulence on Bd's invading front. The impact of Bd on amphibians might therefore be driven by rapid evolution in addition to more proximate environmental drivers. Source

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