Understanding and reversing the habitat shifts that have endangered the broad-headed snake. Extinction rates for vertebrate species are higher in southern Australia than almost anywhere else in the world, and saving endangered taxa is critical to biodiversity conservation. To do this effectively, researchers need to understand the processes that threaten wild populations, and to develop novel solutions to those problems in close collaboration with wildlife management authorities and other stake ....Understanding and reversing the habitat shifts that have endangered the broad-headed snake. Extinction rates for vertebrate species are higher in southern Australia than almost anywhere else in the world, and saving endangered taxa is critical to biodiversity conservation. To do this effectively, researchers need to understand the processes that threaten wild populations, and to develop novel solutions to those problems in close collaboration with wildlife management authorities and other stakeholders. This project will build such an understanding and collaboration, focusing on an endangered snake species. We propose ambitious landscape-scale field experiments that will simultaneously test hypotheses on threatening processes, and restore habitat quality to reverse population declines.Read moreRead less
Is recruitment of marine invertebrates affected by variation in larval quality? Managing marine populations and habitats requires detailed understanding of how populations are replenished, and why some places receive more new recruits than others. Attempts to reach this understanding have been hindered by the difficulty in studying tiny larvae that live in the plankton, and for most species, recruitment is a highly variable, unexplained phenomenon. We have identified a new explanation for this ....Is recruitment of marine invertebrates affected by variation in larval quality? Managing marine populations and habitats requires detailed understanding of how populations are replenished, and why some places receive more new recruits than others. Attempts to reach this understanding have been hindered by the difficulty in studying tiny larvae that live in the plankton, and for most species, recruitment is a highly variable, unexplained phenomenon. We have identified a new explanation for this variation, and will test this explanation using a marine invertebrate that is one of Australia's marine pests. A positive result offers promise of explaining recruitment variation in other species, and will provide insight into what makes this particular pest species successful.Read moreRead less
Comparative population structure of forest invertebrate species - habitat specific or species specific? Invertebrates that colonize decomposing logs are an important link in the food chain and major players in the recycling of forest debris. In addition, many threatened species occupy this habitat. Despite their undoubted economic and conservation significance, there is very little information on distribution, dispersal and population structure for any of these species. We will use genetic tool ....Comparative population structure of forest invertebrate species - habitat specific or species specific? Invertebrates that colonize decomposing logs are an important link in the food chain and major players in the recycling of forest debris. In addition, many threatened species occupy this habitat. Despite their undoubted economic and conservation significance, there is very little information on distribution, dispersal and population structure for any of these species. We will use genetic tools to investigate these patterns, and to determine whether they are specific to particular species, or the product of the habitat itself. Our results will indicate whether forest management strategies should focus on the preservation of individual species or their habitat.Read moreRead less
Resource patchiness, dispersal and species co-occurrence: an experimental and levels-of-evidence approach in some lowland streams. Millions of dollars are being spent on rehabilitating river ecosystems that have often been highly simplified by human activities. It is important that such rehabilitation be well-grounded in sound ecological knowledge. We will test how the availability of essential resources of food and living space affect the identity and density of species present. We expect to p ....Resource patchiness, dispersal and species co-occurrence: an experimental and levels-of-evidence approach in some lowland streams. Millions of dollars are being spent on rehabilitating river ecosystems that have often been highly simplified by human activities. It is important that such rehabilitation be well-grounded in sound ecological knowledge. We will test how the availability of essential resources of food and living space affect the identity and density of species present. We expect to provide practical advice allowing managers to enhance biodiversity in streams surrounded by, and serving, agricultural areas. Likewise, we will be able to advise on the consequences of excessive water extraction on the likely success of such rehabilitation in rivers with highly variable flows.Read moreRead less
How effective are environmental flows? Novel approaches for monitoring and assessing ecological responses to large-scale flow alteration. Australia has begun a multi-billion dollar program to return water to stressed rivers as environmental flows. However, during times of unprecedented water scarcity, such an investment in the environment can be controversial because the ecological benefits of released water are mostly poorly understood. This project will demonstrate the effectiveness of environ ....How effective are environmental flows? Novel approaches for monitoring and assessing ecological responses to large-scale flow alteration. Australia has begun a multi-billion dollar program to return water to stressed rivers as environmental flows. However, during times of unprecedented water scarcity, such an investment in the environment can be controversial because the ecological benefits of released water are mostly poorly understood. This project will demonstrate the effectiveness of environmental flows, and promote greater understanding of the links between flow patterns and river health. The project will build upon existing knowledge to create a sound framework for planning, monitoring, and evaluation of environmental watering decisions across regional Australia, greatly improving our ability to sustainably manage rivers into the future.Read moreRead less
How do plants cope with temporal variability in water and nutrients? Australia's climate and weather are temporally variable, yet we know little of how Australia's flora is affected by temporally variable vs constant supplies of water and nutrients. In addition, climate change will affect our flora by, among other things, increasing temporal variability in water and nutrient availability. This program of research will provide basic data on growth responses to variable vs. constant water and nu ....How do plants cope with temporal variability in water and nutrients? Australia's climate and weather are temporally variable, yet we know little of how Australia's flora is affected by temporally variable vs constant supplies of water and nutrients. In addition, climate change will affect our flora by, among other things, increasing temporal variability in water and nutrient availability. This program of research will provide basic data on growth responses to variable vs. constant water and nutrient availability. Hence, results will be directly applicable to predicting the effects of climate change on growth, species' distribution and community composition. This research will also improve our basic understanding of limitations to photosynthesis, transpiration and nutrient uptake/assimilation.Read moreRead less
How does allocation to each sex evolve in hermaphrodites? New insight from the sea. Understanding the ability of hermaphroditic animals to adapt their sex allocation to suit environmental conditions will pave the way for integration between pure and applied research. Such understanding can provide stakeholders across a range of disciplines (natural resource management, aquaculture, conservation) with key information about genetic and environmental influences on the reproduction of many species o ....How does allocation to each sex evolve in hermaphrodites? New insight from the sea. Understanding the ability of hermaphroditic animals to adapt their sex allocation to suit environmental conditions will pave the way for integration between pure and applied research. Such understanding can provide stakeholders across a range of disciplines (natural resource management, aquaculture, conservation) with key information about genetic and environmental influences on the reproduction of many species of significant ecological, economic and social value with this mating system. This research will yield knowledge at the very forefront of evolutionary ecology, enhancing Australia's reputation for research excellence in this field, and further benefit Australian science through the training of young scientists.Read moreRead less
Drought and Salinity Tolerance in Metal Hyperaccumulating Plants: A Functional Role for the Metals? A few plant species can ?hyperaccumulate? metal ions to 100-1000 times the concentrations seen in ?normal? plants. Just why these plants have evolved such an extreme response to metalliferous soils remains an enigma. Many of the hyperaccumulators so far described are endemic to xeric environments, or saline soils prone to rapid drying. We hypothesize that the metals might act as osmotica, enha ....Drought and Salinity Tolerance in Metal Hyperaccumulating Plants: A Functional Role for the Metals? A few plant species can ?hyperaccumulate? metal ions to 100-1000 times the concentrations seen in ?normal? plants. Just why these plants have evolved such an extreme response to metalliferous soils remains an enigma. Many of the hyperaccumulators so far described are endemic to xeric environments, or saline soils prone to rapid drying. We hypothesize that the metals might act as osmotica, enhancing plant survival during water stress. This will be tested for Australian native and non-native hyperaccumulator plants. The study will clarify our understanding of the evolutionary significance of hyperaccumulation, and has important applications for extracting metals from contaminated soils.Read moreRead less
Diadromous stream fishes: a model system for investigating sources of variation in recruitment. Our aim is to examine the relationship between adult abundance and recruitment in local populations of a diadromous stream fish to identify the source(s) of variation in recruitment. We will accomplish this by measuring larval production and recruitment among streams that vary in adult abundance, strength of settlement cues, and potential for larval dispersal. We will also use environmental markers of ....Diadromous stream fishes: a model system for investigating sources of variation in recruitment. Our aim is to examine the relationship between adult abundance and recruitment in local populations of a diadromous stream fish to identify the source(s) of variation in recruitment. We will accomplish this by measuring larval production and recruitment among streams that vary in adult abundance, strength of settlement cues, and potential for larval dispersal. We will also use environmental markers of larval origin to quantify the degree of self-recruitment and dispersal within/among populations. The results will broaden our understanding of the influence of local (production, habitat) versus regional (dispersal) processes to local population dynamics, information needed for effective stream management.Read moreRead less
Open or closed? Dispersal and recruitment in populations of aquatic invertebrates with spatially distributed resources. The general aim of this research is to examine the contribution of fertilised eggs and recently hatched juveniles to the local population dynamics of some stream invertebrates. It seems likely that these stages act as population 'bottlenecks' , and our research will quantify the relations between these two stages and between neonates and mature larvae. Our research will also ....Open or closed? Dispersal and recruitment in populations of aquatic invertebrates with spatially distributed resources. The general aim of this research is to examine the contribution of fertilised eggs and recently hatched juveniles to the local population dynamics of some stream invertebrates. It seems likely that these stages act as population 'bottlenecks' , and our research will quantify the relations between these two stages and between neonates and mature larvae. Our research will also indicate whether these populations are likely to be closed (i.e., groups of individuals are relatively isolated) along channels or not. We believe our results will show much stream research focuses on the wrong life-stages; practices of river management may need re-assessment.Read moreRead less