Landscape-scale population dynamics of open forests in the Australian monsoon tropics. Over the last century there has been a trend of increasing tree cover in many landscapes. Yet the causes of this globally important ecological phenomenon are poorly understood, but may include the effects of climate, fire, grazing and CO2. We will determine how an area of forest has changed over 50 years in Kakadu National Park, linking forest demography with remote sensing techniques, re-measurement and analy ....Landscape-scale population dynamics of open forests in the Australian monsoon tropics. Over the last century there has been a trend of increasing tree cover in many landscapes. Yet the causes of this globally important ecological phenomenon are poorly understood, but may include the effects of climate, fire, grazing and CO2. We will determine how an area of forest has changed over 50 years in Kakadu National Park, linking forest demography with remote sensing techniques, re-measurement and analysis of long-term tree demography datasets, and simulation models of tree population dynamics on a landscape scale. This will provide a scientific framework to develop sustainable land management and the conservation of Australia's forest biodiversity.Read moreRead less
Aboriginal patch burning and the quest for sustainable fire management. This project aims to document historical changes in the spatial grain of the patch burning mosaic in an Arnhem Land savannah with an unbroken history of management by Aboriginal people, and in adjacent areas where traditional management has ceased. The mosaic's spatial grain will be inferred by mapping the individual ages of the long-lived conifer Callitris intratropica. Prior research has shown that Callitris individuals c ....Aboriginal patch burning and the quest for sustainable fire management. This project aims to document historical changes in the spatial grain of the patch burning mosaic in an Arnhem Land savannah with an unbroken history of management by Aboriginal people, and in adjacent areas where traditional management has ceased. The mosaic's spatial grain will be inferred by mapping the individual ages of the long-lived conifer Callitris intratropica. Prior research has shown that Callitris individuals can be reliably aged, and population structures are very sensitive to fire regimes: saplings only establish if unburnt for 10 years. This research is expected to provide the first direct test of the hypothesis that Aboriginal people maintained fine-grained fire mosaics in savannas, and inform bushfire policy debates.Read moreRead less
Effects of maternal foraging success and oceanographic variation on offspring behaviour and survival in the southern elephant seal. Juvenile survival is the key determinant of mammalian population performance, but the proximate determinants of this have rarely been established in large, long-lived predators. Southern elephant seals, with their concentrated lactation effort and marked separation of energy acquisition (at-sea foraging) and expenditure (on-land lactation) provide an ideal model for ....Effects of maternal foraging success and oceanographic variation on offspring behaviour and survival in the southern elephant seal. Juvenile survival is the key determinant of mammalian population performance, but the proximate determinants of this have rarely been established in large, long-lived predators. Southern elephant seals, with their concentrated lactation effort and marked separation of energy acquisition (at-sea foraging) and expenditure (on-land lactation) provide an ideal model for investigating these factors. In this study, we investigate the partitioning of pre-partum performance (fat acquired in mothers) relative to spatial-temporal variation in ocean productivity and the effect of this expenditure on offspring condition and survival. Here, the final missing link of energy transfer and its effects on offspring will be a major outcome of this project.Read moreRead less