Minimum sizes and habitat areas for viable populations. This project will address two critical issues in conservation biology: How large do wildlife populations need to be to ensure long-term persistence? How large an area needs to be preserved? At present, no such estimates exist for most species. I will develop realistic population viability analysis (PVA) models (encompassing all threats to persistence) on many bird, mammal, reptile, amphibian, invertebrate and plant species, and estimate the ....Minimum sizes and habitat areas for viable populations. This project will address two critical issues in conservation biology: How large do wildlife populations need to be to ensure long-term persistence? How large an area needs to be preserved? At present, no such estimates exist for most species. I will develop realistic population viability analysis (PVA) models (encompassing all threats to persistence) on many bird, mammal, reptile, amphibian, invertebrate and plant species, and estimate the minimum population sizes and habitat areas required for long-term survival. My prior research has validated the predictive accuracy of PVA. This research will deliver practical guidelines for managing threatened species.Read moreRead less
The demographic consequences of migration to, from and within Australia. The long-term demographic consequences of migration to, from and within Australia, and the dynamic pathways that produced them, will be studied. This will involve the identification of the specific contributions made by international and internal migration to the age and sex population compositions of nine birthplace-specific populations from 1981 to 2011. To do this, publically available data will be collected and augmente ....The demographic consequences of migration to, from and within Australia. The long-term demographic consequences of migration to, from and within Australia, and the dynamic pathways that produced them, will be studied. This will involve the identification of the specific contributions made by international and internal migration to the age and sex population compositions of nine birthplace-specific populations from 1981 to 2011. To do this, publically available data will be collected and augmented with statistical methods to provide a complete, consistent account of population change for around 60 subnational areas. As migration and population change underpins many aspects of societal change in Australia, this research aims to provide an invaluable resource to other scientists and policy makers.Read moreRead less
Plant-herbivore interactions: a model two-species system from northern Australia. The proposed research addresses a critical aspect of magpie goose ecology. Understanding the interaction between the birds and the bulbs is critical to respond effectively to past and threatened losses of important sedge habitats to sea level rise. This knowledge will inform management of the Kakadu World Heritage Site and an iconic waterfowl of great cultural and economic significance. In addition to their importa ....Plant-herbivore interactions: a model two-species system from northern Australia. The proposed research addresses a critical aspect of magpie goose ecology. Understanding the interaction between the birds and the bulbs is critical to respond effectively to past and threatened losses of important sedge habitats to sea level rise. This knowledge will inform management of the Kakadu World Heritage Site and an iconic waterfowl of great cultural and economic significance. In addition to their importance as a Gondwanan relic and sole member of the Family Anseranatidae, the species is an important food-source for Aboriginal people, and tourists travel to the Kakadu wetlands to witness huge dry season congregations.Read moreRead less
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
Density regulation as a major determinant of population persistence: advancing empirical and theoretical approaches to conserve biodiversity. Without efficient application of limited conservation resources, more species will go extinct and invasive species will continue to proliferate. With a better understanding of extinction processes, a higher benefit:cost ratio will ensure better outcomes for biodiversity. We will directly address (1) the sustainable use of Australia's biodiversity by provid ....Density regulation as a major determinant of population persistence: advancing empirical and theoretical approaches to conserve biodiversity. Without efficient application of limited conservation resources, more species will go extinct and invasive species will continue to proliferate. With a better understanding of extinction processes, a higher benefit:cost ratio will ensure better outcomes for biodiversity. We will directly address (1) the sustainable use of Australia's biodiversity by providing evidence-based support for minimum viable population size targets to avoid extinction; (2) responding to climate change by determining the species- and environmentally specific contexts leading to elevated risks of extinction; and (3) protecting Australia from invasive diseases and pests by determining density targets that maximise eradication success.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